Polar bear

The numbers taken grew rapidly in the 1960s, peaking around 1968 with a global total of 1,250 bears that year.

Polar bear

In two areas where harvest levels have been increased based on increased sightings, science-based studies have indicated declining populations, and a third area is considered data-deficient.

Polar bear

In 2010, the 2005 increase was partially reversed.

Polar bear

Warnings about the future of the polar bear are often contrasted with the fact that worldwide population estimates have increased over the past 50 years and are relatively stable today.

Polar bear

Of the 19 recognized polar bear subpopulations, one is in decline, two are increasing, seven are stable, and nine have insufficient data, as of 2017.


There's no empirical evidence for climate change.

Biodiversity

Climate change has proven to affect biodiversity and evidence supporting the altering effects is widespread.

Climate change (general concept)

... there is a strong, credible body of evidence, based on multiple lines of research, documenting that climate is changing and that these changes are in large part caused by human activities.

Science

Natural science is concerned with the description, prediction, and understanding of natural phenomena based on empirical evidence from observation and experimentation.

Skepticism

A scientific or empirical skeptic is one who questions beliefs on the basis of scientific understanding and empirical evidence.

Skepticism

Scientific skepticism concerns testing beliefs for reliability, by subjecting them to systematic investigation using the scientific method, to discover empirical evidence for them.


Antarctica

This means that it is a very cold continent where water is mostly in the form of ice.

Captain America: The First Avenger

Producer Avi Arad said, "The biggest opportunity with Captain America is as a man 'out of time', coming back today, looking at our world through the eyes of someone who thought the perfect world was small-town United States.

Captain America: The First Avenger

Sixty years go by, and who are we today?

Captain America: The First Avenger

... We have to deal with much the same way that Captain America, when thawed from the Arctic ice, entered a world that he didn't recognize," similar to the way Stan Lee and Jack Kirby reintroduced the character in the 1960s.

Summit Series

The Summit Series, or Super Series (in Russian Суперсерия СССР — Канада; Superseriya SSSR — Canada), known at the time simply as the Canada–USSR Series, was an eight-game series of ice hockey between the Soviet Union and Canada, held in September 1972.


2009-2010 winter saw record cold spells.

Cold wave

Overall it was the coldest winter since 1978–79, with a mean temperature of 1.5 °C (34.7 °F).

Cold wave

It was the coldest winter and longest cold spell for thirty years in the United Kingdom, whilst temperatures in the Italian Alpine peaks reached low to an extreme of −47 °C (−52.6 °F).

Winter

In Europe, the winters of early 1947, February 1956, 1962–1963, 1981–1982 and 2009–2010 were abnormally cold.

Winter

In the United States, a record five-week cold spell bottomed out at −20 °F (−29 °C) at Hartford, Connecticut, and −16 °F (−27 °C) in New York City.

Winter

2011 was one of the coldest on record in New Zealand with sea level snow falling in Wellington in July for the first time in 35 years and a much heavier snowstorm for 3 days in a row in August.


El Niño

The ENSO cycle, including both El Niño and La Niña, causes global changes in temperature and rainfall.

El Niño

El Nino affects the global climate and disrupts normal weather patterns, which as a result can lead to intense storms in some places and droughts in others.

Humboldt Current

These two species experience population shifts related to climate changes and environmental events such as El Niño.

La Niña

La Niña

"The impact of global warming on the tropical Pacific Ocean and El Niño".


Climate change is because of Pacific Decadal Oscillation.

Climate change (general concept)

Examples include variability in ocean basins such as the Pacific decadal oscillation and Atlantic multidecadal oscillation.

Climate system

"Externally Forced and Internally Generated Decadal Climate Variability Associated with the Interdecadal Pacific Oscillation".

Climate system

Examples of this type of variability include the El Niño–Southern Oscillation, the Pacific decadal oscillation, and the Atlantic Multidecadal Oscillation.

Climate variability

the Pacific decadal oscillation – The dominant pattern of sea surface variability in the North Pacific on a decadal scale.

Pacific decadal oscillation

The Pacific Decadal Oscillation (PDO) is a robust, recurring pattern of ocean-atmosphere climate variability centered over the mid-latitude Pacific basin.


2nd law of thermodynamics contradicts greenhouse theory.

Second law of thermodynamics

The theory of classical or equilibrium thermodynamics is idealized.

Second law of thermodynamics

Loschmidt's paradox, also known as the reversibility paradox, is the objection that it should not be possible to deduce an irreversible process from the time-symmetric dynamics that describe the microscopic evolution of a macroscopic system.

Second law of thermodynamics

The recurrence theorem may be perceived as apparently contradicting the second law of thermodynamics.

Second law of thermodynamics

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations – then so much the worse for Maxwell's equations.

Second law of thermodynamics

Carnot's original arguments were made from the viewpoint of the caloric theory, before the discovery of the first law of thermodynamics.


Cloud

Broadly speaking, if clouds, especially low clouds, increase in a warmer climate, the resultant cooling effect leads to a negative feedback in climate response to increased greenhouse gases.

Cloud

But if low clouds decrease, or if high clouds increase, the feedback is positive.

Negative feedback

A basic and common example of a negative feedback system in the environment is the interaction among cloud cover, plant growth, solar radiation, and planet temperature.

Negative feedback

One such feedback system is the interaction between solar radiation, cloud cover, and planet temperature.

Tropical cyclone

This effect results in a negative feedback process that can inhibit further development or lead to weakening.


Sea level rise predictions are exaggerated.

Sea level rise

A conservative estimate of the long-term projections is that each Celsius degree of temperature rise triggers a sea level rise of approximately 2.3 meters (4.2 ft/degree Fahrenheit) over a period of two millennia: an example of climate inertia.

Sea level rise

More recent research, especially into Antarctica, indicates that this is probably a conservative estimate and true long-term sea level rise might be higher.

Sea level rise

"Scientists keep upping their projections for how much the oceans will rise this century".

Sea level rise

This is an important confirmation of climate change simulations which predicted that sea level rise would accelerate in response to global warming.

Sea level rise

For example, in 2007 the Intergovernmental Panel on Climate Change (IPCC) projected a high end estimate of 60 cm (2 ft) through 2099, but their 2014 report raised the high-end estimate to about 90 cm (3 ft).


Methane is the only cause of climate change.

Global warming

Scientists have determined that the major factors causing the current climate change are greenhouse gases, land use changes, and aerosols and soot.

Greenhouse gas

If this energy balance is shifted, Earth's surface becomes warmer or cooler, leading to a variety of changes in global climate.

Greenhouse gas

A number of natural and man-made mechanisms can affect the global energy balance and force changes in Earth's climate.

Methane

Climate change can increase atmospheric methane levels by increasing methane production in natural ecosystems, forming a Climate change feedback.

Methane

"Tackling Climate Change Through Livestock".


They changed the name from 'global warming' to 'climate change'.

Climate change adaptation

Climate change adaptation (CCA) is a response to global warming (also known as "climate change" or "anthropogenic climate change").

Global warming

"Reduction in surface climate change achieved by the 1987 Montreal Protocol".

Global warming

"Assessing dangerous climate change through an update of the Intergovernmental Panel on Climate Change (IPCC) 'reasons for concern'".

Global warming

In technical sources, the term climate change is also used to refer to past and future climate changes that persist for and extended period of time, and includes regional changes as well as global change.

Global warming


Axial precession

(the angle between the equatorial plane and the ecliptic plane) is the maximum value of δ for the Sun and the average maximum value for the Moon over an entire 18.6 year cycle.

Solar eclipse of August 21, 2017

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles.

Sun

Because energy transport in the Sun is a process that involves photons in thermodynamic equilibrium with matter, the time scale of energy transport in the Sun is longer, on the order of 30,000,000 years.

Sun

The oscillation in the Z direction takes the Sun ( W ( 0 ) ν ) 2 + Z ( 0 ) 2 = 98  parsec {\displaystyle {\sqrt {\left({\frac {W(0)}{\nu }}\right)^{2}+Z(0)^{2}}}=98{\text{ parsec}}} above the galactic plane and the same distance below it, with a period of 2 π / ν {\displaystyle 2\pi /\nu } or 83 million years, approximately 2.7 times per orbit.

Sun

At this speed, it takes around 1,190 years for the Solar System to travel a distance of 1 light-year, or 7 days to travel 1 AU.


Global warming

Global warming is the long-term rise in the average temperature of the Earth's climate system.

IPCC Third Assessment Report

The TAR estimate for the climate sensitivity is 1.5 to 4.5 °C; and the average surface temperature is projected to increase by 1.4 to 5.8 Celsius degrees over the period 1990 to 2100, and the sea level is projected to rise by 0.1 to 0.9 metres over the same period.

Intergovernmental Panel on Climate Change:230

Under the pledges of the countries entering the Paris Accord, a sharp rise of 3.1 to 3.7 °C is still expected to occur by 2100.

Intergovernmental Panel on Climate Change:686

Scientific consensus on climate change:719

Scientific consensus on climate change

On the basis of available data, climate scientists are now projecting an average global temperature rise over this century of 2.0 to 4.5°C.


Antarctica

"A 40-y record reveals gradual Antarctic sea ice increases followed by decreases at rates far exceeding the rates seen in the Arctic".

Antarctica

Models also suggest that the ozone depletion/enhanced polar vortex effect also accounts for the recent increase in sea ice just offshore of the continent.

Arctic Ocean

The mean extent of the ice has been decreasing since 1980 from the average winter value of 15,600,000 km2 (6,023,200 sq mi) at a rate of 3% per decade.

Eocene

During the cooling period, benthic oxygen isotopes show the possibility of ice creation and ice increase during this later cooling.

Eocene

Any ice growth was slowed immensely and would lead to any present ice melting.


Sea level rise

Over the 21st century, this is expected to rise, with glaciers contributing 7 to 24 cm (3 to 9 in) to global sea levels.

Sea level rise

More precise data gathered from satellite radar measurements reveal an accelerating rise of 7.5 cm (3.0 in) from 1993 to 2017, which is a trend of roughly 30 cm (12 in) per century.

Sea level rise

This acceleration is due mostly to human-caused global warming, which is driving thermal expansion of seawater and the melting of land-based ice sheets and glaciers.

Sea level rise

More importantly, the GMSL curve shows a net acceleration, estimated to be at 0.08mm/yr2.

Sea level rise

Climate scientists expect the rate to further accelerate during the 21st century.


Humans are too insignificant to affect global climate.

Global warming

The largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.

Holocene extinction

In order to constitute the Holocene as an extinction event, scientists must determine exactly when anthropogenic greenhouse gas emissions began to measurably alter natural atmospheric levels on a global scale, and when these alterations caused changes to global climate.

Human impact on the environment

Human impact on the environment or anthropogenic impact on the environment includes changes to biophysical environments and ecosystems, biodiversity, and natural resources caused directly or indirectly by humans, including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crisis, and ecological collapse.

Human

Humans have had a dramatic effect on the environment.

Human

Currently, through land development, combustion of fossil fuels, and pollution, humans are thought to be the main contributor to global climate change.


Phil Jones says no global warming since 1995.

Global warming

"Reduction in surface climate change achieved by the 1987 Montreal Protocol".

Global warming

Multiple independently produced instrumental datasets confirm that the 2009–2018 decade was 0.93 ± 0.07 °C warmer than the pre-industrial baseline (1850–1900).

Global warming

The Framework Convention was agreed on in 1992, but global emissions have risen since then.

Global warming

Hockey stick controversy

He said there had probably been no global warming since the 1940s, and "Satellite data show no appreciable warming of the global atmosphere since 1979.


Arctic sea ice loss is matched by Antarctic sea ice gain.

Antarctica

"Mass gains of the Antarctic ice sheet exceed losses".

Antarctica

This ice sheet is constantly gaining ice from snowfall and losing ice through outflow to the sea.

Arctic

The Arctic is affected by current global warming, leading to Arctic sea ice shrinkage, diminished ice in the Greenland ice sheet, and Arctic methane release as the permafrost thaws.

Arctic

The effects of global warming in the Arctic include rising temperatures, loss of sea ice, and melting of the Greenland ice sheet.

Sea ice

"Antarctic ice shelf disintegration triggered by sea ice loss and ocean swell".


Earth

There is a scientific consensus linking human activities to global warming due to industrial carbon dioxide emissions.

Global warming

CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming

In general, since the 2010s, global oil companies do not dispute that climate change exists and is caused by the burning of fossil fuels.

Solar cycle


Over 31,000 scientists signed the OISM Petition Project.

A Scientific Dissent from Darwinism

Critics have noted that of the 105 "scientists" listed on the original 2001 petition, fewer than 20% were biologists, with few of the remainder having the necessary expertise to contribute meaningfully to a discussion of the role of natural selection in evolution.

Art Robinson

The OISM website states that "several members of the Institute's staff are also well known for their work on the Petition Project", and that the petition has "more than 31,000" signatures by scientists.

Art Robinson

Robinson asserted in 2008 that the petition has over 31,000 signatories, with 9,000 of these holding a PhD degree.

Oregon Petition

As of 2013, the petition's website states, "The current list of 31,487 petition signers includes 9,029 PhD; 7,157 MS; 2,586 MD and DVM; and 12,715 BS or equivalent academic degrees.

Project Steve

During the four-day drive A Scientific Support For Darwinism And For Public Schools Not To Teach Intelligent Design As Science gathered 7733 signatures of verifiable scientists.


Less than half of published scientists endorse global warming.

Global warming

Scientific consensus on climate change

Nearly all publishing climate scientists (97–98%) support the consensus on anthropogenic climate change, and the remaining 3% of contrarian studies either cannot be replicated or contain errors.

Scientific consensus on climate change:266

Scientific consensus on climate change

97% of the scientists surveyed agreed that global temperatures had increased during the past 100 years; 84% said they personally believed human-induced warming was occurring, and 74% agreed that "currently available scientific evidence" substantiated its occurrence.

Scientific consensus on climate change:282

Scientific consensus on climate change

76 out of 79 climatologists who "listed climate science as their area of expertise and who also have published more than 50% of their recent peer-reviewed papers on the subject of climate change" believed that mean global temperatures had risen compared to pre-1800s levels.

Scientific consensus on climate change:837

Scientific consensus on climate change

Scientists Reach 100% Consensus on Anthropogenic Global Warming.


A drop in volcanic activity caused warming.

1257 Samalas eruption

Sea surface temperatures too decreased by 0.3–2.2 °C (0.54–3.96 °F), triggering changes in the ocean circulations.

Global warming

increased concentrations of greenhouse gases), solar luminosity, volcanic eruptions, and variations in the Earth's orbit around the Sun.

Paleocene–Eocene Thermal Maximum

Volcanic eruptions of a large magnitude can impact global climate, reducing the amount of solar radiation reaching the Earth's surface, lowering temperatures in the troposphere, and changing atmospheric circulation patterns.

Paleocene–Eocene Thermal Maximum

Further, methane is a potent greenhouse gas as it is released into the atmosphere, so it causes warming, and as the ocean transports this warmth to the bottom sediments, it destabilizes more clathrates.

Triassic–Jurassic extinction event

Massive volcanic eruptions, specifically the flood basalts of the Central Atlantic Magmatic Province (CAMP), would release carbon dioxide or sulfur dioxide and aerosols, which would cause either intense global warming (from the former) or cooling (from the latter).


Plant stomata show higher and more variable CO2 levels.

Photosynthesis

Plant species with the greatest photosynthetic rates and Kranz anatomy showed no apparent photorespiration, very low CO2 compensation point, high optimum temperature, high stomatal resistances and lower mesophyll resistances for gas diffusion and rates never saturated at full sun light.

Stoma

Stomatal density and aperture (length of stomata) varies under a number of environmental factors such as atmospheric CO2 concentration, light intensity, air temperature and photoperiod (daytime duration).

Stoma

These studies imply the plants response to changing CO2 levels is largely controlled by genetics.

Stoma

The CO2 fertiliser effect has been greatly overestimated during Free-Air Carbon dioxide Enrichment (FACE) experiments where results show increased CO2 levels in the atmosphere enhances photosynthesis, reduce transpiration, and increase water use efficiency (WUE).

Stoma

Rates of leaf photosynthesis were shown to increase by 30–50% in C3 plants, and 10–25% in C4 under doubled CO2 levels.


Tuvalu

Because of the low elevation, the islands that make up this nation are vulnerable to the effects of tropical cyclones and by the threat of current and future sea level rise.

Tuvalu

Tuvalu is also affected by perigean spring tide events which raise the sea level higher than a normal high tide.

Tuvalu

Tuvaluan leaders have been concerned about the effects of rising sea levels.

Tuvalu

Gradual sea-level rise also allows for coral polyp activity to increase the reefs.

Tuvalu

Mean sea-level rise is projected to continue (very high confidence).


Renewables can't provide baseload power.

Base load

"Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms".

Geothermal gradient

Generating electrical power from geothermal resources requires no fuel while providing true baseload energy at a reliability rate that constantly exceeds 90%.

Renewable energy

EGS and HDR technologies, such as hydrothermal geothermal, are expected to be baseload resources which produce power 24 hours a day like a fossil plant.

Wind power

about 8% of total nameplate capacity) to be used as reliable, baseload electric power which can be relied on to handle peak loads, as long as minimum criteria are met for wind speed and turbine height.

Wind power

"Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms" (PDF).


Ice sheet

The Greenland, and possibly the Antarctic, ice sheets have been losing mass recently, because losses by ablation including outlet glaciers exceed accumulation of snowfall.

Ice sheet

The IPCC projects that ice mass loss from melting of the Greenland ice sheet will continue to outpace accumulation of snowfall.

Ice sheet

Accumulation of snowfall on the Antarctic ice sheet is projected to outpace losses from melting.

Retreat of glaciers since 1850

Between 2000 and 2016, 29 % of the glacierized area was lost, the remaining area estimated at around 1,300 km2 (500 sq mi).

Retreat of glaciers since 1850

The net loss in volume and hence sea level contribution of the Greenland Ice Sheet (GIS) has doubled in recent years from 90 km3 (22 cu mi) per year in 1996 to 220 km3 (53 cu mi) per year in 2005.


Arctic sea ice decline

The fast rate of the sea ice melting is resulting in the oceans absorbing and heating up the Arctic.

Arctic

The Arctic is affected by current global warming, leading to Arctic sea ice shrinkage, diminished ice in the Greenland ice sheet, and Arctic methane release as the permafrost thaws.

Arctic

The effects of global warming in the Arctic include rising temperatures, loss of sea ice, and melting of the Greenland ice sheet.

Arctic

Release of methane and carbon dioxide stored in permafrost could cause abrupt and severe global warming, as they are potent greenhouse gases.

Global warming

Surface temperature increases are greatest in the Arctic, which has contributed to the retreat of glaciers, permafrost, and sea ice.


Carbon dioxide in Earth's atmosphere:140

Carbon dioxide in Earth's atmosphere

While CO 2 absorption and release is always happening as a result of natural processes, the recent rise in CO 2 levels in the atmosphere is known to be mainly due to human (anthropogenic) activity.

Carbon dioxide

Human activities have caused CO 2 to increase above levels not seen in hundreds of thousands of years.

Carbon sequestration

These reactions are exothermic and occur naturally (e.g., the weathering of rock over geologic time periods).

Geysers on Mars

Martian geysers (or CO 2 jets) are putative sites of small gas and dust eruptions that occur in the south polar region of Mars during the spring thaw.

Global warming

Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions and persistent anthropogenic changes in the composition of the atmosphere or in land use."


97% consensus on human-caused global warming has been disproven.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming

In a 2019 CBS poll, 64% of the US population said that climate change is a "crisis" or a "serious problem", with 44% saying human activity was a significant contributor.

Scientific consensus on climate change:10

Scientific consensus on climate change

Of these, 97% agree, explicitly or implicitly, that global warming is happening and is human-caused.

Scientific consensus on climate change:19

Scientific consensus on climate change

It is extremely likely (95–100% probability) that human influence was the dominant cause of global warming between 1951–2010.

Scientific consensus on climate change

97% of the scientists surveyed agreed that global temperatures had increased during the past 100 years; 84% said they personally believed human-induced warming was occurring, and 74% agreed that "currently available scientific evidence" substantiated its occurrence.


Water vapor in the stratosphere stopped global warming.

Atmospheric methane

This process is enhanced by global warming, because warmer air holds more water vapor than colder air, so the amount of water vapor in the atmosphere increases as it is warmed by the greenhouse effect.

Global warming

According to basic physical principles, the greenhouse effect produces warming of the lower atmosphere (the troposphere), but cooling of the upper atmosphere (the stratosphere).

Global warming

After an initial warming due to emissions of greenhouse gases, the atmosphere will hold more water.

Runaway greenhouse effect

An increase in temperature from greenhouse gases leading to increased water vapor (which is itself a greenhouse gas) causing further warming is a positive feedback, but not a runaway effect, on Earth.

Water vapor

When water vapour condenses onto a surface, a net warming occurs on that surface.


Adapting to global warming is cheaper than preventing it.

Climate change adaptation

Adaptation is especially important in developing countries since those countries are bearing the brunt of the effects of global warming.

Climate change mitigation

"Eat less meat to avoid dangerous global warming, scientists say".

Global warming

Successful adaptation is easier if there are substantial emission reductions.

Global warming

Adaptation is especially important in developing countries since they are predicted to bear the brunt of the effects of global warming.

Global warming

The capacity and potential for humans to adapt, called adaptive capacity, is unevenly distributed across different regions and populations, and developing countries generally have less capacity to adapt.


CERN CLOUD experiment proved cosmic rays are causing global warming.

Cosmic ray

Danish physicist Henrik Svensmark has controversially argued that because solar variation modulates the cosmic ray flux on Earth, they would consequently affect the rate of cloud formation and hence be an indirect cause of global warming.

Cosmic ray

"Sun's Shifts May Cause Global Warming".

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Henrik Svensmark

He is known for his theory on the effects of cosmic rays on cloud formation as an indirect cause of global warming.

Henrik Svensmark

"Cosmic rays blamed for global warming".


Sun

Sunspots are visible as dark patches on the Sun's photosphere, and correspond to concentrations of magnetic field where the convective transport of heat is inhibited from the solar interior to the surface.

Sun

At this point in the dynamo cycle, buoyant upwelling within the convective zone forces emergence of toroidal magnetic field through the photosphere, giving rise to pairs of sunspots, roughly aligned east–west and having footprints with opposite magnetic polarities.

Sun

Long-term secular change in sunspot number is thought, by some scientists, to be correlated with long-term change in solar irradiance, which, in turn, might influence Earth's long-term climate.

Sunspot

Sunspots number is correlated with the intensity of solar radiation over the period since 1979, when satellite measurements became available.

Sunspot

On longer time scales, such as the solar cycle, other magnetic phenomena (faculae and the chromospheric network) correlate with sunspot occurrence.


Antarctica

As a result of continued warming, the polar ice caps melted and much of Gondwana became a desert.

Antarctica

This means that it is a very cold continent where water is mostly in the form of ice.

Antarctica

Offshore, temperatures are also low enough that ice is formed from seawater through most of the year.

Antarctica

This ice sheet is constantly gaining ice from snowfall and losing ice through outflow to the sea.

Antarctica

The continent has about 90% of the world's ice (and thus about 70% of the world's fresh water).


Climate change in Tuvalu

Gradual sea-level rise also allows for coral polyp activity to raise the atolls with the sea level.

Coral reef

As communities established themselves, the reefs grew upwards, pacing rising sea levels.

Coral reef

Healthy tropical coral reefs grow horizontally from 1 to 3 cm (0.39 to 1.18 in) per year, and grow vertically anywhere from 1 to 25 cm (0.39 to 9.84 in) per year; however, they grow only at depths shallower than 150 m (490 ft) because of their need for sunlight, and cannot grow above sea level.

Coral reef

Atolls may also be formed by the sinking of the seabed or rising of the sea level.

Tuvalu

Gradual sea-level rise also allows for coral polyp activity to increase the reefs.


CO2 increase is natural, not human-caused.

Carbon dioxide in Earth's atmosphere

While CO 2 absorption and release is always happening as a result of natural processes, the recent rise in CO 2 levels in the atmosphere is known to be mainly due to human (anthropogenic) activity.

Carbon dioxide

Human activities have caused CO 2 to increase above levels not seen in hundreds of thousands of years.

Global warming

Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs, and nitrous oxide.

Greenhouse gas

[clarification needed] This increase is the result of human activities by burning fossil fuels, deforestation and forest degradation in tropical and boreal regions.

Greenhouse gas

It is likely that anthropogenic (i.e., human-induced) warming, such as that due to elevated greenhouse gas levels, has had a discernible influence on many physical and biological systems.


Scientists retracted claim that sea levels are rising.

Global warming

Sea level rise will continue over many centuries.

Global warming

rising sea levels, shrinking Arctic sea ice).

Global warming

The effects of global warming include rising sea levels, regional changes in precipitation, more frequent extreme weather events such as heat waves, and expansion of deserts.

Sea level rise

Since at least the start of the 20th century, the average global sea level has been rising.

Sea level rise

"Scientists keep upping their projections for how much the oceans will rise this century".


BP

It established an alternative and low carbon energy business in 2005, with plans to invest $8 billion over a 10-year period into renewable energy sources including solar, wind, and biofuels, and non-renewable sources including natural gas and hydrogen power.

Green-collar worker

Some 2.3 million people have found renewable energy jobs in recent years, and projected investments of $630 billion by 2030 would translate into at least 20 million additional jobs.

Green-collar worker

In the context of the current world economic crisis, many experts now argue that a massive push to develop renewable sources of energy could create millions of new jobs and help the economy recover while simultaneously improving the environment, increasing labour conditions in poor economies, and strengthening energy and food security.

Renewable energy commercialization

A key benefit that this investment growth brings is a growth in jobs.

Renewable energy

Globally there are an estimated 7.7 million jobs associated with the renewable energy industries, with solar photovoltaics being the largest renewable employer.


Carbon dioxide

Less energy reaches the upper atmosphere, which is therefore cooler because of this absorption.

Carbon dioxide

Occupational CO 2 exposure limits have been set in the United States at 0.5% (5000 ppm) for an eight-hour period.

Gaia hypothesis

As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet.

Global warming

Global warming is the long-term rise in the average temperature of the Earth's climate system.

Global warming

If cloud cover increases, more sunlight will be reflected back into space, cooling the planet.


Schmittner finds low climate sensitivity.

Earth's energy budget

Climate sensitivity is the steady state change in the equilibrium temperature as a result of changes in the energy budget.

Electronic keyboard

They are not sensitive to the climate or humidity changes in a room and there is also no need for tuning, as with acoustic pianos.

Land degradation

Sensitivity is the degree to which a land system undergoes change due to natural forces, human intervention or a combination of both.

Mediterranean Sea

Because of its latitude and its land-locked position, the Mediterranean is especially sensitive to astronomically induced climatic variations, which are well documented in its sedimentary record.

Perennial plant

Herbaceous perennials are also able to tolerate the extremes of cold in temperate and Arctic winters, with less sensitivity than trees or shrubs.


Greenland has only lost a tiny fraction of its ice mass.

Greenland ice sheet

If iceberg calving has happened as an average, Greenland lost 294 Gt of its mass during 2007 (one km3 of ice weighs about 0.9 Gt).

Greenland

Findings show that Greenland has lost 3.8 trillion tonnes of ice since 1992, enough to raise sea levels by almost 11mm (1.06cm).

Greenland

The rate of ice loss has increased from an average of 33 billion tonnes a year in the 1990s, to 254 billion tonnes a year in the last decade.

Retreat of glaciers since 1850

Between 2000 and 2016, 29 % of the glacierized area was lost, the remaining area estimated at around 1,300 km2 (500 sq mi).

Retreat of glaciers since 1850

Between then and 2010, the mountain lost 80 percent of its ice — two-thirds of which since another scientific expedition in the 1970s.


Arctic sea ice extent was lower in the past.

Arctic Ocean

The mean extent of the ice has been decreasing since 1980 from the average winter value of 15,600,000 km2 (6,023,200 sq mi) at a rate of 3% per decade.

Climate change in the Arctic

The Arctic sea ice September minimum extent (i.e., area with at least 15% sea ice coverage) reached new record lows in 2002, 2005, 2007, and 2012.

Polar ice cap

In August 2013, Arctic sea ice extent averaged 6.09m km2, which represents 1.13 million km2 below the 1981–2010 average for that month.

Sea ice

In comparison to the extended record, the sea-ice extent in the polar region by September 2007 was only half the recorded mass that had been estimated to exist within the 1950–1970 period.

Sea ice

Arctic sea ice extent ice hit an all-time low in September 2012, when the ice was determined to cover only 24% of the Arctic Ocean, offsetting the previous low of 29% in 2007.


Climate change isn't increasing extreme weather damage costs.

Climate change adaptation

This causes a variety of secondary effects, namely, changes in patterns of precipitation, rising sea levels, altered patterns of agriculture, increased extreme weather events, the expansion of the range of tropical diseases, and the opening of new marine trade routes.

Economic impacts of climate change

Many analyses, such as that of the Stern Review presented to the British Government, have predicted reductions by several percent of world gross domestic product due to climate related costs such as dealing with increased extreme weather events and stresses to low-lying areas due to sea level rises.

Effects of global warming

Global losses reveal rapidly rising costs due to extreme weather-related events since the 1970s.

Heat wave

Global warming boosts the probability of extreme weather events, like heat waves, far more than it boosts more moderate events.

Intergovernmental Panel on Climate Change:159

"Impacts [of climate change] will very likely increase due to increased frequencies and intensities of some extreme weather events".


UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong.

John Christy

We have found that climate models and popular surface temperature data sets overstate the changes in the real atmosphere and that actual changes are not alarming."

Microwave Sounding Unit temperature measurements:111

Globally, most climate models used by the IPCC in preparation of their third assessment in 2007 show a slightly greater warming at the TLT level than at the surface (0.03 °C/decade difference) for 1979–1999 while the GISS trend is +0.161 °C/decade for 1979 to 2012, the lower troposphere trends calculated from satellite data by UAH and RSS are +0.130 °C/decade and +0.206 °C/decade.

Microwave Sounding Unit temperature measurements:92

Specifically, surface data showed substantial global-average warming, while early versions of satellite and radiosonde data showed little or no warming above the surface.

UAH satellite temperature dataset

In comparing these measurements to surface temperature models, it is important to note that values for the lower troposphere measurements taken by the MSU are a weighted average of temperatures over multiple altitudes (roughly 0 to 12 km), and not a surface temperature (as seen in figure above).

UAH satellite temperature dataset

The results are thus not precisely comparable to surface temperature records or models.


IPCC human-caused global warming attribution confidence is unfounded.

Attribution of recent climate change

The IPCC's attribution of recent global warming to human activities is a view shared by the scientific community, and is also supported by 196 other scientific organizations worldwide (see also: Scientific consensus on climate change).

IPCC Fifth Assessment Report

There is a clear human influence on the climate It is extremely likely that human influence has been the dominant cause of observed warming since 1950, with the level of confidence having increased since the fourth report.

Intergovernmental Panel on Climate Change:127

Since the mid-20th century, most of the observed warming is "likely" (greater than 66% probability, based on expert judgement) due to human activities.

Intergovernmental Panel on Climate Change:190

It is extremely likely (95-100% probability) that human influence was the dominant cause of global warming between 1951-2010.

Scientific consensus on climate change:306

Scientific consensus on climate change

They provide an analysis of what is known and not known, the degree of consensus, and some indication of the degree of confidence that can be placed on the various statements and conclusions."


We didn't have global warming during the Industrial Revolution.

20th century

The average global temperature on Earth has increased by about 0.8° Celsius (1.4° Fahrenheit) since 1880; Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20 °C per decade.

Global warming

Climate proxy records show that natural variations offset the early effects of the Industrial Revolution, so there was little net warming between the 18th century and the mid-19th century, when thermometer records began to provide global coverage.

Global warming

Before the Industrial Revolution, naturally occurring amounts of greenhouse gases caused the air near the surface to be warmer by about 33 °C (59 °F) than it would be in their absence.

Global warming

Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs, and nitrous oxide.

Scientific consensus on climate change:713

Scientific consensus on climate change

Human activities resulting from the industrial revolution have changed the chemical composition of the atmosphere....Deforestation is now the second largest contributor to global warming, after the burning of fossil fuels.


Hansen predicted in 1988 the West Side Highway would be underwater in 20 years.

James Hansen

When the analysis was updated in 1988, the four warmest years on record were all in the 1980s.

James Hansen

During a senate meeting on June 23, 1988, Hansen reported that he was ninety-nine percent certain the earth was warmer then than it had ever been measured to be, there was a clear cause and effect relationship with the greenhouse effect and lastly that due to global warming, the likelihood of freak weather was steadily increasing.

West Side Highway

The West Side Highway (officially the Joe DiMaggio Highway) is a 5.42-mile-long (8.72 km) mostly surface section of New York State Route 9A (NY 9A) that runs from West 72nd Street along the Hudson River to the southern tip of Manhattan in New York City.

West Side Highway

Construction began in early 1996 on the West Side Highway project.

West Side Highway

"After 20 Years of Delays, a River Park Takes Shape".


Crown-of-thorns starfish

The Great Barrier Reef (GBR) is the most outstanding coral reef system in the world because of its great length, number of individual reefs and species diversity.

Great Barrier Reef

The percentage of baby corals being born on the Great Barrier Reef dropped drastically in 2018 and scientists are describing it as the early stage of a "huge natural selection event unfolding".

Great Barrier Reef

The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms.

Great Barrier Reef

In the northern part of the Great Barrier Reef, ribbon reefs and deltaic reefs have formed; these structures are not found in the rest of the reef system.

Great Barrier Reef

Crescentic reefs are the most common shape of reef in the middle of the system, for example the reefs surrounding Lizard Island.


Effective temperature

One reason for the difference between the two values is due to the greenhouse effect, which increases the average temperature of the Earth's surface.

Global warming

Simultaneously, the clouds enhance the greenhouse effect, warming the planet.

Greenhouse effect

It was demonstrated experimentally (R. W. Wood, 1909) that a (not heated) "greenhouse" with a cover of rock salt (which is transparent to infrared) heats up an enclosure similarly to one with a glass cover.

Ice age

The consensus theory of the scientific community is that the resulting greenhouse effect is a principal cause of the increase in global warming which has occurred over the same period, and a chief contributor to the accelerated melting of the remaining glaciers and polar ice.

Ice age

The ice age continues until the reduction in weathering causes an increase in the greenhouse effect.


Underground temperatures control climate.

Climate

Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation.

Climate

Increases in greenhouse gases, such as by volcanic activity, can increase the global temperature and produce an interglacial period.

Climate

Any imbalance results in a change in the average temperature of the earth.

Climate

Alterations in the quantity of atmospheric greenhouse gases determines the amount of solar energy retained by the planet, leading to global warming or global cooling.

Climate

Ice caps form because high-latitude regions receive less energy as solar radiation from the sun than equatorial regions, resulting in lower surface temperatures.


Global warming is increasing the risk of heatwaves.

Global warming

Climate change also increases droughts and heat waves that inhibit plant growth, which makes it uncertain whether this balancing feedback will persist in the future.

Global warming

Many regions have probably already seen increases in warm spells and heat waves, and it is virtually certain that these changes will continue over the 21st century.

Global warming

Since the 1950s, droughts and heat waves have appeared simultaneously with increasing frequency.

Global warming

The effects of global warming include rising sea levels, regional changes in precipitation, more frequent extreme weather events such as heat waves, and expansion of deserts.

Heat wave

Global warming boosts the probability of extreme weather events, like heat waves, far more than it boosts more moderate events.


Climate reacts to whatever forces it to change at the time; humans are now the dominant forcing.

Attribution of recent climate change

Human activities can also impose forcings, for example, through changing the composition of the atmosphere.

Climate system

Volcanic eruptions, solar variations and anthropogenic changes in the composition of the atmosphere and land use change are external forcings.

Climate system

These external forcings can be natural, such as variations in solar intensity and volcanic eruptions, or caused by humans.

Global warming

Other changes are caused by external forcings.

Global warming

Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions and persistent anthropogenic changes in the composition of the atmosphere or in land use."


In the last 35 years of global warming, sun and climate have been going in opposite directions.

Attribution of recent climate change

Over the past five decades there has been a global warming of approximately 0.65 °C (1.17 °F) at the Earth's surface (see historical temperature record).

Climate

Climate change may occur over long and short timescales from a variety of factors; recent warming is discussed in global warming.

Global warming controversy

"Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature" (PDF).

Global warming

Currently, surface temperatures are rising by about 0.2 °C per decade.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.


97% of climate experts agree humans are causing global warming.

21st century

Climate scientists have reached a consensus that the earth is undergoing significant anthropogenic (human-induced) global warming.

Global warming

Scientific consensus on climate change

Of these, 97% agree, explicitly or implicitly, that global warming is happening and is human-caused.

Scientific consensus on climate change

97% of the scientists surveyed agreed that global temperatures had increased during the past 100 years; 84% said they personally believed human-induced warming was occurring, and 74% agreed that "currently available scientific evidence" substantiated its occurrence.

Scientific consensus on climate change:289

Scientific consensus on climate change

They found 4,014 which discussed the cause of recent global warming, and of these "97.1% endorsed the consensus position that humans are causing global warming".


The warming trend is the same in rural and urban areas, measured by thermometers and satellites.

Global warming

In areas with high soot production, such as rural India, as much as 50% of surface warming due to greenhouse gases may be masked by atmospheric brown clouds.

Urban heat island

For example, urban and rural trends are very similar.

Urban heat island

In fact, the lower-tropospheric temperatures warm at a slightly greater rate over North America (about 0.28°C/decade using satellite data) than do the surface temperatures (0.27°C/decade), although again the difference is not statistically significant.

Urban heat island

This was done by using satellite-based night-light detection of urban areas, and more thorough homogenisation of the time series (with corrections, for example, for the tendency of surrounding rural stations to be slightly higher in elevation, and thus cooler, than urban areas).

Urban heat island

After trends were adjusted in urban weather stations around the world to match rural stations in their regions, in an effort to homogenise the temperature record, in 42 percent of cases, cities were getting cooler relative to their surroundings rather than warmer.


Satellites measure Antarctica losing land ice at an accelerating rate.

Antarctica

"A 40-y record reveals gradual Antarctic sea ice increases followed by decreases at rates far exceeding the rates seen in the Arctic".

Antarctica

found instead that the net change in ice mass is slightly positive at approximately 82 gigatonnes per year (with significant regional variation) which would result in Antarctic activity reducing global sea-level rise by 0.23 mm per year.

Antarctica

A satellite record revealed that the overall increase in Antarctic sea ice extents reversed in 2014, with rapid rates of decrease in 2014–2017 reducing the Antarctic sea ice extents to their lowest values in the 40-y record.

Retreat of glaciers since 1850

More recently, new satellite imaging data led to calculations of Thwaites Glacier "ice shelf melt rate of 207 m/year in 2014–2017, which is the highest ice shelf melt rate on record in Antarctica."

Sea level rise

All datasets generally show an acceleration of mass loss from the Antarctic ice-sheet, but with year-to-year variations.


Worry about global warming impacts in the next 100 years, not an ice age in over 10,000 years.

Global catastrophic risk

These global climatic changes occurred slowly, prior to the rise of human civilization about 10 thousand years ago near the end of the last Major Ice Age when the climate became more stable.

Global catastrophic risk

[citation needed] The amount of heat trapping gases emitted into Earth's Oceans and atmosphere will prevent the next ice age, which otherwise would begin in around 50,000 years, and likely more glacial cycles.

Global warming

Global anthropogenic greenhouse gas emissions in 2010 were equivalent to 49 billion tonnes of carbon dioxide (using the most recent global warming potentials over 100 years from the AR5 report).

Ice age

(Current projected consequences of global warming include a largely ice-free Arctic Ocean within 5–20 years, see Arctic shrinkage.)

Intergovernmental Panel on Climate Change:128

Projections based on the Special Report on Emissions Scenarios suggest warming over the 21st century at a more rapid rate than that experienced for at least the last 10,000 years.


Recent studies agree that recent global temperatures are unprecedented in the last 1000 years.

Global warming

Currently, surface temperatures are rising by about 0.2 °C per decade.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming

The period from 1983 to 2012 was likely the warmest 30-year period of the last 1400 years in the Northern Hemisphere, where such assessment is possible (medium confidence).

Scientific consensus on climate change:48

Scientific consensus on climate change

Global warming in this case was indicated by an increase of 0.75 degrees in average global temperatures over the last 100 years.

Scientific consensus on climate change:507

Scientific consensus on climate change

Since the start of the 20th century, the global mean surface temperature of the Earth has increased by more than 0.7°C and the rate of warming has been largest in the last 30 years.


Al Gore's book is quite accurate, and far more accurate than contrarian books.

Al Gore

In a 2007 court case, a British judge said that while he had "no doubt ...the film was broadly accurate" and its "four main scientific hypotheses ...are supported by a vast quantity of research", he upheld nine of a "long schedule" of alleged errors presented to the court.

An Inconvenient Truth

All 19 climate scientists who had seen the movie or had read the homonymous book said that Gore accurately conveyed the science, with few errors.

An Inconvenient Truth

"He is making a qualitative point, which is entirely accurate.

An Inconvenient Truth

The story is scientifically accurate and yet should be understandable to the public, a public that is less and less drawn to science."

Earth in the Balance

Earth in the Balance: Ecology and the Human Spirit (ISBN 0-452-26935-0, paperback ISBN 1-85383-743-1) is a 1992 book written by Al Gore, published in June 1992, shortly before he was elected Vice President in the 1992 presidential election.


Most glaciers are retreating, posing a serious problem for millions who rely on glaciers for water.

Effects of global warming on human health:459

Earth's glaciers are expected to melt within the next forty years, greatly decreasing fresh water flow in the hotter times of the year, causing everyone to depend on rainwater, resulting in large shortages and fluctuations in fresh water availability which largely effects agriculture, power supply, and human health and well-being.

Glacier

Following the Little Ice Age's end around 1850, glaciers around the Earth have retreated substantially.

Glacier

A slight cooling led to the advance of many alpine glaciers between 1950 and 1985, but since 1985 glacier retreat and mass loss has become larger and increasingly ubiquitous.

Retreat of glaciers since 1850

In areas that are heavily dependent on water runoff from glaciers that melt during the warmer summer months, a continuation of the current retreat will eventually deplete the glacial ice and substantially reduce or eliminate runoff.

Water scarcity

Climate change has caused receding glaciers, reduced stream and river flow, and shrinking lakes and ponds.


Cosmic rays show no trend over the last 30 years & have had little impact on recent global warming.

Global warming

Scientific consensus on climate change:150

Scientific consensus on climate change

Human-caused increases in greenhouse gases are responsible for most of the observed global average surface warming of roughly 0.8 °C (1.5 °F) over the past 140 years.

Scientific consensus on climate change

Scientific consensus on climate change

Solar activity and climate

estimated that the residual effects of the prolonged high solar activity during the last 30 years account for between 16% and 36% of warming from 1950 to 1999.


Extreme weather events are being made more frequent and worse by global warming.

Global issue

Other likely changes include more frequent extreme weather events such as heat waves, droughts, wildfires, heavy rainfall with floods, and heavy snowfall; ocean acidification; and massive extinctions of species due to shifting temperature regimes.

Global warming

Impacts include the direct effects of extreme weather, leading to injury and loss of life; and indirect effects, such as undernutrition brought on by crop failures.

Global warming

The effects of global warming include rising sea levels, regional changes in precipitation, more frequent extreme weather events such as heat waves, and expansion of deserts.

Heat wave

Global warming boosts the probability of extreme weather events, like heat waves, far more than it boosts more moderate events.

Weather

Climate change caused by human activities that emit greenhouse gases into the air is expected to affect the frequency of extreme weather events such as drought, extreme temperatures, flooding, high winds, and severe storms.


A variety of different measurements find steadily rising sea levels over the past century.

Global warming

Between 1993 and 2017, the global mean sea level rose on average by 3.1 ± 0.3 mm per year, with an acceleration detected as well.

Sea level rise

Since at least the start of the 20th century, the average global sea level has been rising.

Sea level rise

Between 1900 and 2016, the sea level rose by 16–21 cm (6.3–8.3 in).

Sea level rise

More precise data gathered from satellite radar measurements reveal an accelerating rise of 7.5 cm (3.0 in) from 1993 to 2017, which is a trend of roughly 30 cm (12 in) per century.

Sea level rise

Since the last glacial maximum about 20,000 years ago, the sea level has risen by more than 125 metres (410 ft), with rates varying from less than a mm/year to 40+ mm/year, as a result of melting ice sheets over Canada and Eurasia.


Urban and rural regions show the same warming trend.

Urban heat island

On the other hand, one 1999 comparison between urban and rural areas proposed that urban heat island effects have little influence on global mean temperature trends.

Urban heat island

For example, urban and rural trends are very similar.

Urban heat island

Not all cities show a warming relative to their rural surroundings.

Urban heat island

Surfaces in the urban areas tend to warm faster than those of the surrounding rural areas.

Urbanization

For North America and Europe, such practice could reduce earth warming trends.


The strong CO2 effect has been observed by many different measurements.

Atmosphere of Venus

The large amount of CO2 in the atmosphere together with water vapour and sulfur dioxide create a strong greenhouse effect, trapping solar energy and raising the surface temperature to around 740 K (467 °C), hotter than any other planet in the Solar System, even that of Mercury despite being located farther out from the Sun and receiving only 25% of the solar energy (per unit area) Mercury does.

Carbon dioxide

There are few studies of the health effects of long-term continuous CO 2 exposure on humans and animals at levels below 1%.

Carbon dioxide

A study of humans exposed in 2.5 hour sessions demonstrated significant negative effects on cognitive abilities at concentrations as low as 0.1% (1000 ppm) CO 2 likely due to CO 2 induced increases in cerebral blood flow.

Global warming

The warming evident in the instrumental temperature record is consistent with a wide range of observations, documented by many independent scientific groups; for example, in most continental regions the frequency and intensity of heavy precipitation has increased.

Physical impacts of climate change

Large-scale measurements of sea-ice have only been possible since the satellite era, but through looking at a number of different satellite estimates, it has been determined that September Arctic sea ice has decreased between 1973 and 2007 at a rate of about -10% +/- 0.3% per decade.


The most recent ocean measurements show consistent warming.

Global warming

Instrumental temperature record

The global average and combined land and ocean surface temperature, show a warming of 0.85 [0.65 to 1.06] °C, in the period 1880 to 2012, based on multiple independently produced datasets.

Physical impacts of climate change

From 1961 to 2003, the global ocean temperature has risen by 0.10 °C from the surface to a depth of 700 m. There is variability both year-to-year and over longer time scales, with global ocean heat content observations showing high rates of warming for 1991 to 2003, but some cooling from 2003 to 2007.

Scientific consensus on climate change:391

Scientific consensus on climate change

"Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level."

Scientific consensus on climate change:49

Scientific consensus on climate change

The IPCC Fourth Assessment Report stated that: Warming of the climate system is unequivocal, as evidenced by increases in global average air and ocean temperatures, the widespread melting of snow and ice, and rising global average sea level.


Climate scientists could make far more money in other careers - most notably, working for the oil industry.

Climate change denial

He has accepted more than $1.2 million in money from the fossil-fuel industry over the last decade while failing to disclose that conflict of interest in most of his scientific papers.

Global warming controversy

reducing emissions/consumption) and for the prolonging of profits to the oil industry at the expense of the environment.

Global warming controversy

One of the authors' main arguments is that most prominent scientists who have been voicing opposition to the near-universal consensus are being funded by industries, such as automotive and oil, that stand to lose money by government actions to regulate greenhouse gases.

Jim Inhofe

According to the Center for Responsive Politics, Inhofe has received over $529,000 from the oil and gas industry since 2012.

Russia

Russia has an upper-middle income mixed economy with enormous natural resources, particularly oil and natural gas.


Ancient natural cycles are irrelevant for attributing recent global warming to humans.

Climate change (general concept)

Anthropogenic climate change is caused by human activity, as opposed to changes in climate that may have resulted as part of Earth's natural processes.

Earth

There is a scientific consensus linking human activities to global warming due to industrial carbon dioxide emissions.

Global warming

The effects of climate change on human systems, mostly due to warming and shifts in precipitation, have been detected worldwide.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming

Attributing detected temperature changes and extreme events to human-caused increases in greenhouse gases requires scientists to rule out known internal climate variability and natural external forcings.


The natural cycle adds and removes CO2 to keep a balance; humans add extra CO2 without removing any.

Carbon capture and storage

The CO 2 is removed after combustion of fossil fuels, but before the flue gas is expanded to atmospheric pressure.

Carbon cycle

Since the industrial revolution, human activity has modified the carbon cycle by changing its components' functions and directly adding carbon to the atmosphere.

Carbon cycle

Another direct human impact on the carbon cycle is the chemical process of calcination of limestone for clinker production, which releases CO 2.

Carbon sequestration

Various carbon dioxide scrubbing processes have been proposed to remove CO 2 from the air, usually using a variant of the Kraft process.

Climate change mitigation

The reason for this is that human activities are adding CO2 to the atmosphere faster than natural processes can remove it (see carbon dioxide in Earth's atmosphere for a complete explanation).


Numerous papers have documented how IPCC predictions are more likely to underestimate the climate response.

IPCC First Assessment Report

There are many uncertainties in our predictions particularly with regard to the timing, magnitude and regional patterns of climate change, due to our incomplete understanding of: sources and sinks of GHGs; clouds; oceans; polar ice sheets.

Intergovernmental Panel on Climate Change:113

They judge that global mean surface air temperature has increased by 0.3 to 0.6 °C over the last 100 years, broadly consistent with prediction of climate models, but also of the same magnitude as natural climate variability.

Projections based on the Special Report on Emissions Scenarios suggest warming over the 21st century at a more rapid rate than that experienced for at least the last 10,000 years.

Intergovernmental Panel on Climate Change:292

Some critics have contended that the IPCC reports tend to be conservative by consistently underestimating the pace and impacts of global warming, and report only the "lowest common denominator" findings.

Intergovernmental Panel on Climate Change:296

Another example of scientific research which suggests that previous estimates by the IPCC, far from overstating dangers and risks, have actually understated them is a study on projected rises in sea levels.


Rising CO2 increases atmospheric water vapor, which makes global warming much worse.

Carbon dioxide

Increases in atmospheric concentrations of CO 2 and other long-lived greenhouse gases such as methane, nitrous oxide and ozone have correspondingly strengthened their absorption and emission of infrared radiation, causing the rise in average global temperature since the mid-20th century.

Carbon dioxide

Not only do increasing carbon dioxide concentrations lead to increases in global surface temperature, but increasing global temperatures also cause increasing concentrations of carbon dioxide.

Carbon dioxide

Since the Industrial Revolution anthropogenic emissions – primarily from use of fossil fuels and deforestation – have rapidly increased its concentration in the atmosphere, leading to global warming.

Global warming

Higher atmospheric CO2 concentrations have led to an increase in dissolved CO2, which causes ocean acidification.

Greenhouse gas

Indirectly, human activity that increases global temperatures will increase water vapor concentrations, a process known as water vapor feedback.


Polar bears are in danger of extinction as well as many other species.

Global warming

Environmental impacts include the extinction or relocation of many species as their ecosystems change, most immediately the environments of coral reefs, mountains, and the Arctic.

Global warming

Overall, it is expected that climate change will result in the extinction of many species and reduced diversity of ecosystems.

Holocene extinction

"Global habitat loss and extinction risk of terrestrial vertebrates under future land-use-change scenarios".

Holocene extinction

There is widespread consensus among scientists that human activity is accelerating the extinction of many animal species through the destruction of habitats, the consumption of animals as resources, and the elimination of species that humans view as threats or competitors.

Polar bear

The key danger posed by climate change is malnutrition or starvation due to habitat loss.


The benefits of a price on carbon outweigh the costs several times over.

Carbon credit

The optimal carbon price, or optimal carbon tax, is the market price (or carbon tax) on carbon emissions that balances the incremental costs of reducing carbon emissions with the incremental benefits of reducing climate damages.

Carbon price

Suppose the benefits from that ton range from $1 for the user with the least need for carbon to $100 (in $1 increments) for the user who would benefit most.

Carbon price

How much does that cost the US (excluding the benefit of the reduced externality)?

Carbon price

So that is sometimes said to be the cost of the policy.

Carbon tax

Carbon emissions have an "unpriced" societal cost in terms of their deleterious effects on the earth's climate.


Other parts of the earth got colder when Greenland got warmer.

Antarctica

As a result of continued warming, the polar ice caps melted and much of Gondwana became a desert.

Atlantic Ocean

In the higher latitudes, the North Atlantic Drift, warms the atmosphere over the oceans, keeping the British Isles and north-western Europe mild and cloudy, and not severely cold in winter like other locations at the same high latitude.

Earth

"Coldest temperature ever recorded on Earth in Antarctica".

Earth

The climate is colder at high altitudes than at sea level because of the decreased air density.

Polar regions of Earth

Polar regions receive less intense solar radiation than the other parts of Earth because the sun's energy arrives at an oblique angle, spreading over a larger area, and also travels a longer distance through the Earth's atmosphere in which it may be absorbed, scattered or reflected, which is the same thing that causes winters to be colder than the rest of the year in temperate areas.


Greenland on the whole is losing ice, as confirmed by satellite measurement.

Greenland ice sheet

These measurements came from the US space agency's GRACE (Gravity Recovery and Climate Experiment) satellite, launched in 2002, as reported by BBC.

Greenland ice sheet

Play media Satellite measurements of Greenland's ice cover from 1979 to 2009 reveals a trend of increased melting.

Greenland

This glacier was discovered in 2002 to be shrinking rapidly, and by 2007 had completely melted away, leaving the exposed island.

Greenland

Findings show that Greenland has lost 3.8 trillion tonnes of ice since 1992, enough to raise sea levels by almost 11mm (1.06cm).

Greenland

"Greenland Glaciers Losing Ice Much Faster, Study Says".


The effects of enhanced CO2 on terrestrial plants are variable and complex and dependent on numerous factors.

Biodiversity

Increasing atmospheric carbon dioxide certainly affects plant morphology and is acidifying oceans, and temperature affects species ranges, phenology, and weather, but, mercifully, the major impacts that have been predicted are still potential futures.

Carbon dioxide

Carbon fixation is a biochemical process by which atmospheric carbon dioxide is incorporated by plants, algae and (cyanobacteria) into energy-rich organic molecules such as glucose, thus creating their own food by photosynthesis.

Carbon dioxide

The concentration of secondary metabolites such as phenylpropanoids and flavonoids can also be altered in plants exposed to high concentrations of CO 2.

Climate change and agriculture

Elevated atmospheric carbon dioxide affects plants in a variety of ways.

Sustainability

The environmental effects of different dietary patterns depend on many factors, including the proportion of animal and plant foods consumed and the method of food production.


Mars and Jupiter are not warming, and anyway the sun has recently been cooling slightly.

Jupiter

Brown ovals are warmer and located within the "normal cloud layer".

Jupiter

Infrared observation showed a bright spot where the impact took place, meaning the impact warmed up the lower atmosphere in the area near Jupiter's south pole.

Mars

Martian surface temperatures vary from lows of about −143 °C (−225 °F) at the winter polar caps to highs of up to 35 °C (95 °F) in equatorial summer.

Mars

The summer temperatures in the south can be warmer than the equivalent summer temperatures in the north by up to 30 °C (54 °F).

Mars

Observations by the Mars Reconnaissance Orbiter had previously revealed the possibility of flowing water during the warmest months on Mars.


Thick arctic sea ice is in rapid retreat.

Holocene glacial retreat

The Holocene glacial retreat is a geographical phenomenon that involved the global deglaciation of glaciers that previously had advanced during the Last Glacial Maximum.

North Pole

The retreat of the Arctic sea ice will accelerate global warming, as less ice cover reflects less solar radiation, and may have serious climate implications by contributing to Arctic cyclone generation.

Retreat of glaciers since 1850

In 2002 the 12 km (7.5 mi) long floating terminus of the glacier entered a phase of rapid retreat, with the ice front breaking up and the floating terminus disintegrating and accelerating to a retreat rate of over 30 m (98 ft) per day.

Retreat of glaciers since 1850

"Fast-flow advance and parallel rapid retreat of non-surging tidewater glaciers in Icy Bay and Yakutat Bay, Alaska 1888–2003".

Sea ice

A composite record of Arctic ice demonstrates that the floes' retreat began around 1900, experiencing more rapid melting beginning within the past 50 years.


There is long-term correlation between CO2 and global temperature; other effects are short-term.

An Inconvenient Truth

Gore's use of long ice core records of CO2 and temperature (from oxygen isotope measurements) in Antarctic ice cores to illustrate the correlation between the two drew some scrutiny; Schmidt, Steig and Michael E. Mann back up Gore's data.

Climate change (general concept)

During the glacial cycles, there was a high correlation between CO 2 concentrations and temperatures.

El Niño–Southern Oscillation

El Niño events cause short-term (approximately 1 year in length) spikes in global average surface temperature while La Niña events cause short term cooling.

Little Ice Age

This trend could be extrapolated to continue into the future, possibly leading to a full ice age, but the twentieth-century instrumental temperature record shows a sudden reversal of this trend, with a rise in global temperatures attributed to greenhouse gas emissions.

Paleoclimatology

There is also a close correlation between CO2 and temperature, where CO2 has a strong control over global temperatures in Earth history.


Scientists have determined that the factors which caused the Little Ice Age cooling are not currently causing global warming.

Global warming

Historical patterns of warming and cooling, like the Medieval Climate Anomaly and the Little Ice Age, were not as synchronous as current warming, but may have reached temperatures as high as those of the late-20th century in a limited set of regions.

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming

Scientists have determined that the major factors causing the current climate change are greenhouse gases, land use changes, and aerosols and soot.

Ice age

The consensus theory of the scientific community is that the resulting greenhouse effect is a principal cause of the increase in global warming which has occurred over the same period, and a chief contributor to the accelerated melting of the remaining glaciers and polar ice.

James Hansen

The temperature data was updated in 2006 to report that temperatures are now 0.8 °C warmer than a century ago, and concluded that the recent global warming is a real climate change and not an artifact from the urban heat island effect.


Global temperature is still rising and 2010 was the hottest recorded.

2010 Northern Hemisphere heat waves

In Israel, the year 2010 was the hottest on record, and average temperatures were 2-3 degrees Celsius higher than the average.

Global warming

Global warming is the long-term rise in the average temperature of the Earth's climate system.

Global warming

Between 1993 and 2017, the global mean sea level rose on average by 3.1 ± 0.3 mm per year, with an acceleration detected as well.

Global warming

Currently, surface temperatures are rising by about 0.2 °C per decade.

Moscow

The highest temperature ever recorded was 38.2 °C (100.8 °F) at the VVC weather station and 39.0 °C (102.2 °F) in the center of Moscow and Domodedovo airport on July 29, 2010 during the unusual 2010 Northern Hemisphere summer heat waves.


When CO2 was higher in the past, the sun was cooler.

Greenhouse effect

Because the Earth's surface is colder than the Sun, it radiates at wavelengths that are much longer than the wavelengths that were absorbed.

Greenhouse effect

Because the Earth is much colder than the Sun, it radiates at much longer wavelengths, primarily in the infrared part of the spectrum (see Figure 1).

Greenhouse gas

If this energy balance is shifted, Earth's surface becomes warmer or cooler, leading to a variety of changes in global climate.

Ice age

Glacials are characterized by cooler and drier climates over most of the earth and large land and sea ice masses extending outward from the poles.

Ice age

The reflection of energy into space resulted in a global cooling, triggering the Pleistocene Ice Age.


Early 20th century warming is due to several causes, including rising CO2.

20th century

The largest contribution to total radiative forcing is caused by the increase in the atmospheric concentration of CO2 since 1750."

20th century

The average global temperature on Earth has increased by about 0.8° Celsius (1.4° Fahrenheit) since 1880; Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20 °C per decade.

20th century

One argument is that of global warming occurring due to human-caused emission of greenhouse gases, particularly carbon dioxide produced by the burning of fossil fuels.

Global warming

CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change.

James Hansen

Decades ago, they correctly predicted how much Earth's temperature would rise due to increasing atmospheric CO2.


The most recent satellite data show that the earth as a whole is warming.

Earth

"Evidence is now 'unequivocal' that humans are causing global warming – UN report".

Earth

This is predicted to produce changes such as the melting of glaciers and ice sheets, more extreme temperature ranges, significant changes in weather and a global rise in average sea levels.

Global cooling

The current scientific consensus on climate change is that the Earth underwent global warming throughout the 20th century and continues to warm.

James Hansen

The temperature data was updated in 2006 to report that temperatures are now 0.8 °C warmer than a century ago, and concluded that the recent global warming is a real climate change and not an artifact from the urban heat island effect.

Sea level rise

The last time the Earth was 2 °C (3.6 °F) warmer than pre-industrial temperatures, sea levels were at least 5 metres (16 ft) higher than now: this was when warming because of changes in the amount of sunlight due to slow changes in the Earth's orbit caused the last interglacial.


A cold day in Chicago in winter has nothing to do with the trend of global warming.

Chicago

The lake also provides another positive effect: moderating Chicago's climate, making waterfront neighborhoods slightly warmer in winter and cooler in summer.

Climate change in the United States

In it was the prediction that on our current course the planet will warm a disastrous seven degrees Fahrenheit (or about 3.9 degrees Celsius) by the end of this century.

Global warming

Global warming is the long-term rise in the average temperature of the Earth's climate system.

Global warming

"What caused the recent "Warm Arctic, Cold Continents" trend pattern in winter temperatures?".

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.


No known natural forcing fits the fingerprints of observed warming except anthropogenic greenhouse gases.

Global warming

Attributing detected temperature changes and extreme events to human-caused increases in greenhouse gases requires scientists to rule out known internal climate variability and natural external forcings.

Global warming

Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs, and nitrous oxide.

Global warming

The largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.

Global warming

Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions and persistent anthropogenic changes in the composition of the atmosphere or in land use."

Scientific consensus on climate change:511

Scientific consensus on climate change

The spatial and temporal fingerprint of warming can be traced to increasing greenhouse gas concentrations in the atmosphere, which are a direct result of burning fossil fuels, broad-scale deforestation and other human activity."


The PDO shows no trend, and therefore the PDO is not responsible for the trend of global warming.

Effects of global warming

Some of the graphs show a positive trend, e.g., increasing temperature over land and the ocean, and sea level rise.

Global warming hiatus

"Recently amplified arctic warming has contributed to a continual global warming trend".

Global warming in Antarctica

The Antarctic Peninsula (AP) is often described as a region with one of the largest warming trends on Earth since the 1950s, based on the temperature trend of 0.54 °C/decade during 1951–2011 recorded at Faraday/Vernadsky station.

Global warming

Global warming

There has been no upward trend in the amount of the Sun's energy reaching the Earth, so it cannot be responsible for the current warming.


The 2nd law of thermodynamics is consistent with the greenhouse effect which is directly observed.

Second law of thermodynamics

This does not conflict with notions that have been observed of the fundamental laws of physics, namely CPT symmetry, since the second law applies statistically, it is hypothesized, on time-asymmetric boundary conditions.

Second law of thermodynamics

Thermodynamics

The second law is an observation of the fact that over time, differences in temperature, pressure, and chemical potential tend to even out in a physical system that is isolated from the outside world.

Thermodynamics

There are many versions of the second law, but they all have the same effect, which is to explain the phenomenon of irreversibility in nature.

Water vapor

This greenhouse forcing is directly observable, via distinct spectral features versus water vapor, and observed to be rising with rising CO 2 levels.


Weather and climate are different; climate predictions do not need weather detail.

Chaos theory

Lorenz's discovery, which gave its name to Lorenz attractors, showed that even detailed atmospheric modelling cannot, in general, make precise long-term weather predictions.

Climate

A humid continental climate is marked by variable weather patterns and a large seasonal temperature variance.

European Centre for Medium-Range Weather Forecasts:32

Reanalysis provides a four-dimensional picture of the atmosphere and effectively allows monitoring of the variability and change of global climate, thereby contributing also to the understanding and attribution of climate change.

Met Office

The Met Office makes meteorological predictions across all timescales from weather forecasts to climate change.

Scientific consensus on climate change:137

Scientific consensus on climate change

Documented long-term climate changes include changes in Arctic temperatures and ice, widespread changes in precipitation amounts, ocean salinity, wind patterns and extreme weather including droughts, heavy precipitation, heat waves and the intensity of tropical cyclones.


Those who contribute the least greenhouse gases will be most impacted by climate change.

Global warming

Many of the countries that have contributed least to global greenhouse gas emissions are among the most vulnerable to climate change, which raises questions about justice and fairness with regard to mitigation and adaptation.

Global warming

The largest human influence has been the emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.

Greenhouse gas

Cumulative anthropogenic (i.e., human-emitted) emissions of CO 2 from fossil fuel use are a major cause of global warming, and give some indication of which countries have contributed most to human-induced climate change.

Holocene extinction

Large populations of megaherbivores have the potential to contribute greatly to the atmospheric concentration of methane, which is an important greenhouse gas.

Holocene extinction

However, damage to peatland contributes to 4% of global greenhouse gas emissions, and 8% of those caused by burning fossil fuels.


Evidence is building that net cloud feedback is likely positive and unlikely to be strongly negative.

Evidence-based medicine

Large effect: This is when methodologically strong studies show that the observed effect is so large that the probability of it changing completely is less likely.

Evidence-based medicine

A 2007 analysis of 1,016 systematic reviews from all 50 Cochrane Collaboration Review Groups found that 44% of the reviews concluded that the intervention was likely to be beneficial, 7% concluded that the intervention was likely to be harmful, and 49% concluded that evidence did not support either benefit or harm.

Evidence

Global warming controversy

Other analyses have found that the iris effect is a positive feedback rather than the negative feedback proposed by Lindzen.

Global warming controversy

One theory is that the climate may reach a "tipping point" where positive feedback effects lead to runaway global warming; such feedbacks include decreased reflection of solar radiation as sea ice melts, exposing darker seawater, and the potential release of large volumes of methane from thawing permafrost.


That human CO2 is causing global warming is known with high certainty & confirmed by observations.

Attribution of recent climate change

Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent global warming and related climate changes on Earth.

Carbon dioxide

"How do we know more CO2 is causing warming?".

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Greenhouse gas

During the late 20th century, a scientific consensus evolved that increasing concentrations of greenhouse gases in the atmosphere cause a substantial rise in global temperatures and changes to other parts of the climate system, with consequences for the environment and for human health.

Sea level rise

This acceleration is due mostly to human-caused global warming, which is driving thermal expansion of seawater and the melting of land-based ice sheets and glaciers.


Sea level rise is now increasing faster than predicted due to unexpectedly rapid ice melting.

Sea level rise

Since the last glacial maximum about 20,000 years ago, the sea level has risen by more than 125 metres (410 ft), with rates varying from less than a mm/year to 40+ mm/year, as a result of melting ice sheets over Canada and Eurasia.

Sea level rise

Sea level rise

"Antarctica ice melt has accelerated by 280% in the last 4 decades".

Sea level rise

"Greenland's Coastal Ice Caps Have Melted Past The Point Of No Return".

Sea level rise

Under the influence of global warming, melt at the base of the ice sheet increases.


The oceans are warming and moreover are becoming more acidic, threatening the food chain.

Ocean acidification

Ocean acidification is the ongoing decrease in the pH of the Earth's oceans, caused by the uptake of carbon dioxide (CO 2) from the atmosphere.

Ocean acidification

Ongoing acidification of the oceans may threaten future food chains linked with the oceans.

Ocean acidification

With the production of CO2 from the burning of fossil fuels, oceans are becoming more acidic since CO2 dissolves in water and forms the acidic bicarbonate ion.

Ocean acidification

"Rising Acidity Is Threatening Food Web of Oceans, Science Panel Says".

Ocean acidification

"Ocean Growing More Acidic Faster Than Once Thought; Increasing Acidity Threatens Sea Life".


Around 97% of climate experts agree that humans are causing global warming.

21st century

Climate scientists have reached a consensus that the earth is undergoing significant anthropogenic (human-induced) global warming.

Climate change denial

Several researchers have concluded that around 97% of climate scientists agree with this consensus.

Global warming

Scientific consensus on climate change:10

Scientific consensus on climate change

Of these, 97% agree, explicitly or implicitly, that global warming is happening and is human-caused.

Scientific consensus on climate change:266

Scientific consensus on climate change

97% of the scientists surveyed agreed that global temperatures had increased during the past 100 years; 84% said they personally believed human-induced warming was occurring, and 74% agreed that "currently available scientific evidence" substantiated its occurrence.


Methane plays a minor role in global warming but could get much worse if permafrost starts to melt.

Atmospheric methane

"Methane release from melting permafrost could trigger dangerous global warming".

Atmospheric methane

With rising global temperatures, the amount of permafrost melting and releasing methane continues to increase.

Global warming

Arctic amplification also causes methane to be released as permafrost melts, which is expected to surpass land use changes as the second strongest anthropogenic source of greenhouse gases by the end of the century.

Permafrost

It is thought that permafrost thawing could exacerbate global warming by releasing methane and other hydrocarbons, which are powerful greenhouse gases.

Permafrost

The consequence is thawing soil, which may be weaker, and release of methane, which contributes to an increased rate of global warming as part of a feedback loop.


CO2 levels are measured by hundreds of stations across the globe, all reporting the same trend.

Carbon dioxide in Earth's atmosphere:153

Carbon dioxide in Earth's atmosphere

The Integrated Carbon Observation System (ICOS) continuously releases data about CO 2 emissions, budget and concentration at individual observation stations.

Carbon dioxide in Earth's atmosphere:163

Carbon dioxide in Earth's atmosphere

Now measurements are made at many sites globally.

Carbon dioxide in Earth's atmosphere:167

Carbon dioxide in Earth's atmosphere

There are several surface measurement (including flasks and continuous in situ) networks including NOAA/ERSL, WDCGG, and RAMCES.

Carbon dioxide

Concentrations also vary on a regional basis, most strongly near the ground with much smaller variations aloft.

Greenhouse gas

Measured atmospheric concentrations of carbon dioxide are currently 100 ppm higher than pre-industrial levels.


Multiple lines of independent evidence indicate humidity is rising and provides positive feedback.

Confirmation bias

Self-verification is the drive to reinforce the existing self-image and self-enhancement is the drive to seek positive feedback.

Confirmation bias

Similar experiments have found a preference for positive feedback, and the people who give it, over negative feedback.

Global warming

The main reinforcing feedbacks are the water vapour feedback, the ice–albedo feedback, and probably the net effect of clouds.

Global warming

The warming evident in the instrumental temperature record is consistent with a wide range of observations, documented by many independent scientific groups; for example, in most continental regions the frequency and intensity of heavy precipitation has increased.

Positive feedback

Less water vapor means both low dew point temperatures and more efficient daytime heating, decreasing the chances of humidity in the atmosphere leading to cloud formation.


Hundreds of flowers across the UK are flowering earlier now than any time in 250 years.

Cherry blossom

Cherry blossom

Cherry blossom

Cherry blossom

Cherry blossom

Peak bloom time at Royal Botanical Gardens is normally around the last week of April or the first week of May.


CO2 is increasing rapidly, and is reaching levels not seen on the earth for millions of years.

Carbon cycle

On 12 November 2015, NASA scientists reported that carbon dioxide in the atmosphere from human sources continues to increase, reaching levels not seen in hundreds of thousands of years.

Carbon dioxide in Earth's atmosphere

The present concentration is the highest for 14 million years.

Carbon dioxide

Human activities have caused CO 2 to increase above levels not seen in hundreds of thousands of years.

Carbon dioxide

Increases in atmospheric concentrations of CO 2 and other long-lived greenhouse gases such as methane, nitrous oxide and ozone have correspondingly strengthened their absorption and emission of infrared radiation, causing the rise in average global temperature since the mid-20th century.

Carbon dioxide

The current concentration is about 0.04% (410 ppm) by volume, having risen from pre-industrial levels of 280 ppm.


The 'decline' refers to a decline in northern tree-rings, not global temperature, and is openly discussed in papers and the IPCC reports.

Climatic Research Unit documents

The implications of the decline are discussed in Chapter 2 of the IPCC Third Assessment Report, and in Chapter 6 of the 2007 IPCC Fourth Assessment Report (AR4) which describes discussion of various possible reasons for the divergence which does not affect all the trees, and says that there is no consensus about the cause.

Climatic Research Unit documents

Several scientific sources state that the decline being referred to is a decline in tree ring climate proxy metrics, not temperature.

Climatic Research Unit documents

The issues with tree rings had not been hidden, but were extensively discussed in scientific literature and in IPCC reports.

Climatic Research Unit email controversy:44

This "decline" referred to the well-discussed tree-ring divergence problem, but these two phrases were taken out of context by global warming sceptics, including US Senator Jim Inhofe and former Governor of Alaska Sarah Palin, as though they referred to some decline in measured global temperatures, even though they were written when temperatures were at a record high.

Global warming

Scientific discussion takes place in journal articles that are peer-reviewed, which scientists subject to assessment every couple of years in the Intergovernmental Panel on Climate Change reports.


Global warming' and 'climate change' mean different things and have both been used for decades.

Global warming

Global warming and climate change are often used interchangeably.

Global warming

Research in the 1950s suggested that temperatures were increasing, and a 1952 newspaper used the term "climate change".

Global warming

Both the terms global warming and climate change were used only occasionally until 1975, when Wallace Smith Broecker published a scientific paper on the topic, "Climatic Change: Are We on the Brink of a Pronounced Global Warming?".

Global warming

In technical sources, the term climate change is also used to refer to past and future climate changes that persist for and extended period of time, and includes regional changes as well as global change.

Global warming

NOAA, 17 June 2015; IPCC AR5 SYR Glossary 2014, p. 120: "Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.


The sun has not warmed since 1970 and so cannot be driving global warming.

Effects of global warming

It is a major aspect of climate change, and has been demonstrated by the instrumental temperature record which shows global warming of around 1 °C since the pre-industrial period, although the bulk of this (0.9°C) has occurred since 1970.

Global warming

Since the 1950s, droughts and heat waves have appeared simultaneously with increasing frequency.

Global warming

Multiple independently produced instrumental datasets confirm that the 2009–2018 decade was 0.93 ± 0.07 °C warmer than the pre-industrial baseline (1850–1900).

Global warming

In the scientific literature, there is an overwhelming consensus that global surface temperatures have increased in recent decades and that the trend is caused mainly by human-induced emissions of greenhouse gases.

Global warming


The ocean is absorbing massive amounts of CO2, and is becoming more acidic as a result.

Ocean acidification

Ocean acidification is the ongoing decrease in the pH of the Earth's oceans, caused by the uptake of carbon dioxide (CO 2) from the atmosphere.

Ocean acidification

With the production of CO2 from the burning of fossil fuels, oceans are becoming more acidic since CO2 dissolves in water and forms the acidic bicarbonate ion.

Ocean acidification

The ocean would not become acidic even if it were to absorb the CO2 produced from the combustion of all fossil fuel resources.

Ocean acidification

It is expected to drop by a further 0.3 to 0.5 pH units (an additional doubling to tripling of today's post-industrial acid concentrations) by 2100 as the oceans absorb more anthropogenic CO 2, the impacts being most severe for coral reefs and the Southern Ocean.

Ocean acidification

Although the natural absorption of CO 2 by the world's oceans helps mitigate the climatic effects of anthropogenic emissions of CO 2, it is believed that the resulting decrease in pH will have negative consequences, primarily for oceanic calcifying organisms.


Monckton used the IPCC equation in an inappropriate manner.

Christopher Monckton, 3rd Viscount Monckton of Brenchley:20

Since 2002 Monckton has had several newspaper articles published critical of the IPCC and current scientific consensus on climate change.

General circulation model

The 2001 IPCC Third Assessment Report F igure 9.3 shows the global mean response of 19 different coupled models to an idealised experiment in which emissions increased at 1% per year.

Global warming

"Assessing dangerous climate change through an update of the Intergovernmental Panel on Climate Change (IPCC) 'reasons for concern'".

Radiative forcing

The Intergovernmental Panel on Climate Change (IPCC) AR4 report defines radiative forcings as: "Radiative forcing is a measure of the influence a factor has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system and is an index of the importance of the factor as a potential climate change mechanism.

Radiative forcing

While recently a suggests a significant revision of methane IPCC formula.


Theory, models and direct measurement confirm CO2 is currently the main driver of climate change.

Climate change feedback

Following Le Chatelier's principle, the chemical equilibrium of the Earth's carbon cycle will shift in response to anthropogenic CO2 emissions.

Global warming

It is a major aspect of climate change and has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.

Global warming

In 1896, he published the first climate model of its kind, showing that halving of CO 2 could have produced the drop in temperature initiating the ice age.

Global warming

Scientists have determined that the major factors causing the current climate change are greenhouse gases, land use changes, and aerosols and soot.

Scientific modelling

Models are typically used when it is either impossible or impractical to create experimental conditions in which scientists can directly measure outcomes.