| It's gettin' hot in here|
| Not just a river in Egypt|
|♫ We're not listening ♫|
|—Katharine Hayhoe, climate scientist and evangelical Christian|
Global warming, also known as anthropogenic (or human-caused) global warming, is the rising average temperature of Earth's atmosphere and oceans and its related effects, sometimes popularly summarized as climate change. Global-warming denialism refers to claims — funded by the fossil-fuel industry — that global warming:
- A) is not happening
- B) is not caused by humans
- C) is not significant enough to be a threat
- D) is not important
- E) is beneficial - highlight positive effects (e.g., crops grow faster and could grow crops in the Arctic) while ignoring strong evidence for negative effects (e.g., crops will have lower nutrient levels)
- F) is unsolvable even if it is real (i.e., there is nothing we can do about it)
Global-warming denialism should not be confused with those who accept that anthropogenic global warming is a major threat, but dispute whether or not government regulations put in place to combat it result in a desirable outcome.
- 1 Anthropogenic climate change
- 2 Denial tactics
- 2.1 Which makes more sense?
- 2.2 The denialist staircase
- 2.3 NASA and the Y2K bug
- 2.4 Glacier retreat calculations
- 2.5 Nature generates more CO2 than humans
- 2.6 CO2 levels lag behind temperature increases
- 2.7 Water vapour is a more important greenhouse gas
- 2.8 It has been hotter in the past so it is just cyclical
- 2.9 Global warming has more to do with the Sun than the Earth
- 2.10 Urban heat islands
- 2.11 Hey look! There's been no global warming since 1998
- 2.12 Using anecdotal evidence
- 2.13 Claiming there is no consensus in respect of global warming
- 2.14 Antarctic sea ice is increasing
- 2.15 Global cooling?
- 2.16 Anthony Watts vs NOAA
- 2.17 Climategate
- 3 Snarl words
- 4 Effects
- 5 Conspiracies
- 6 What about that ozone thing?
- 7 In a nutshell
- 8 See also
- 9 External links
- 10 Notes
- 11 References
Anthropogenic climate change
“”Increasing carbon emissions in the atmosphere are having a warming effect.
|—ExxonMobil, paid shills of the denia... oh, wait|
The phrase “global warming” by itself is often used to refer to the rapid rise in temperatures that the Earth has experienced since the start of the Industrial Revolution. In the last 100 years, Earth's average surface temperature increased by about 0.8 °C (1.4 °F) with about two thirds of the increase occurring over just the last three decades. As a result, anthropogenic global warming has recently become a major concern for humanity. Such concerns are supported worldwide by the wide majority of climatologists.
Global warming is an increase in temperature in addition to the natural greenhouse effect. The greenhouse effect interacts with other planet-wide influences such as the Milankovitch cycles in order to produce long-term climate movements. Many gases contribute to the greenhouse effect, some of the most important being water vapor, methane and carbon dioxide. Black carbon (i.e. soot) is third only to carbon dioxide and methane for its contribution to global warming, but it is the most effective at raising temperatures in the Arctic by reducing the albedo.
In its simplest form, the argument for anthropogenic climate change goes as follows.
- The Earth's atmosphere keeps the planet much warmer than it would be without an atmosphere.
- The main gases which contribute to this are carbon dioxide (CO2), methane and water vapor. Collectively these are called greenhouse gases (GHGs).
- The ability of these gases to act as greenhouse gases can be shown in a laboratory.
- The quantity of these greenhouse gases in the atmosphere has increased sharply since the Industrial Revolution, and their concentration continues to do so.
- The concentration of these gases has increased as a consequence of human activity.
- The temperature of Earth's atmosphere has been increasing and continues to increase.
- The increase in global temperature correlates with the increases of greenhouse gases.
Up to this point virtually all scientists are in agreement — including those few global warming "skeptics" who understand the science and the data. Consequently the "skeptics" need to somehow attack the final leg of the argument:
The logical consequence of this conclusion is that we should reduce the quantity of greenhouse gases which we pump into the atmosphere so as to reduce global warming.
Note that the statement that The increase in global temperature correlates with the increases of greenhouse gases is only true on a very broad timescale: GHGs have increased roughly exponentially but the temperature signal is far noisier, and displays almost no correlation with GHG changes on an annual basis, as expected. This is due to a variety of factors, from intrinsic noise in the climate system to the existence of other important forcing factors (most notably sulphate aerosols and global dimming, which are cooling factors).
Also note that while water vapour is correctly listed as a GHG, the human emissions of water vapor are not important in forcing climate change; water vapour is best thought of as a response to temperature change rather than a cause, because its atmospheric lifetime is very short (about 10 days), unlike other gases such as CO2.
What's the limit?
While projections of the potential (maximum) temperature rise resulting from a doubling of CO2 have ranged from 2°C to 6°C, there's broad agreement that anything above 2°C will mean we are beyond recovery. The International Energy Agency suggests that the window to prevent this from occurring will close by 2020, a view shared by the OECD. So let's get cracking.
CO2 emissions have been stabilizing but methane emissions have risen dramatically during the past ten years for unknown reasons. This undermines efforts to combat global warming and there is a risk of an uncontrollable runaway greenhouse effect.
A scientific consensus is reached when the vast majority of the scientists involved in a discipline broadly agree on the interpretation of the evidence pertaining to a specific scientific question. When this occurs the case can be considered to have been demonstrated and the burden of proof then falls on those who would dispute the consensus. The following national and international organizations are part of the consensus that global warming is a real phenomenon for which humans are responsible:
- National Academy of Sciences (NAS)
- National Oceanic and Atmospheric Administration (NOAA)
- NASA's Goddard Institute of Space Studies (GISS)
- Environmental Protection Agency (EPA)
- Royal Society (UK)
- Canadian Meteorological and Oceanographic Society (CMOS)
- UN's Intergovernmental Panel on Climate Change (IPCC)
- And many more.
Though some have taken non-committal stances, the vast majority of scientific bodies are convinced by the evidence. In addition, those pinko tree-huggers at the Pentagon now rank global warming as a "destabilizing force" (damn enviro-weenies).
Despite the clarity of the facts, behavioral/social science tells us that simply shoving global warming related scientific data into their face simply solidifies their existing beliefs. There's even a college offering free online classes that teaches you both the science of what is going on and how to fight denialism properly.
National or international scientific bodies that reject anthropogenic global warming
These options are not necessarily mutually exclusive, but some options are likely to be less costly or more effective than others.
Reducing or stopping human CO2 output
Anyone who, even after the occurrence of extreme weather events that seem to intensify yearly, does not see the validity of decades of scientific documentation that catalogues the existence of global warming, is a lost cause. Simply put, time is of the essence. Instead of spending resources trying to convince people (anyone who still doesn't get it will never get it) that global warming is in fact real, the people in this world who have a clue should put the focus on action and moving forward by championing the solutions to this crisis that threatens all of humanity. These solutions involve fostering the use of hybrid/electric vehicles, and replacing fossil fuels with wind power, solar power, nuclear power, and perhaps hydro power. (Fun fact: Solar power's contribution to global warming is 2-4 times worse than nuclear, per kWh.)
One form of Enhanced Oil Recovery consists in injecting CO2 into reservoirs in order to extract more oil. Ongoing experiments aim at obtaining the CO2 from clean coal plants equipped with carbon capture technology. Although the technology itself seems to work, it is not clear how sequestering coal CO2 to help produce more oil will affect atmospheric CO2.
Scrubbing atmospheric CO2
Air capture technology to collect CO2 is routinely used in spacecraft and submarines. However, it requires energy to operate and a 2011 study estimated that processing the whole atmosphere would not be cost-effective. One of the authors noted that planting vegetation is more feasible but would require a significant amount of land. However, this shouldn't discourage efforts to help reduce the effects of emissions, and in theory could act as a supplement to other methods of CO2 scrubbing. One good example of plants that consume plenty of CO2 are pine trees used in farming. Though they tend to use the nutrients in the ground, in theory they can be replenished from biosolids (refined animal feces). A problem with plants is what to do with all the dead plant matter. Decomposing plants release CH4, an even worse greenhouse gas than CO2, and there is simply not enough storage on earth for all the wood forests of the needed magnitude that we'd need. However, we could bury the resulting biomass underground, in effect recreating the origin of the fossil fuels that got us into this mess in the first place.
Living with it
Climate change is expected to affect farming practices by requiring a shift in corn planting windows. In order to address this, Illinois scientists have suggested various cropping strategies for flexible risk management: planting early so that droughts don't affect harvests, or creating cropping systems that can keep the soil moist through droughts to complement drought-resistant cultivars.
It has long been known that trees are effective in carbon capture. In 2019, an analysis was published on the potential carbon capture and cost effectiveness from reforestation. The study estimated that there is a potential for 0.9 billion hectares in the world that could be reforested, that would eventually result in the storage of 205 gigatonnes of carbon, about "two-thirds of extra carbon from human activities put into the atmosphere since the industrial revolution." The authors of the study estimated that it was the most cost effective strategy available for reducing atmospheric carbon, but that it could not solve global warming without reductions in global carbon emissions. The paper's results are not without critics in the science community.
This involves trying to force climate change back in the opposite direction intentionally, or with what has been described as terraforming Earth. Among these options is lacing the atmosphere with particulate matter in order to seed clouds, artificial carbon sequestration technology to actively remove the carbon dioxide from the atmosphere at a rate faster than natural sinks such as photosynthesis and ocean carbonates, and constructing sun screens in orbit. The pessimistic perspective is that these measures carry additional risks as we've already severely damaged the environment accidentally because we didn't understand it well enough, and any more messing about is liable to make things far worse and far sooner. If that becomes the case, we may have little choice but to attempt more extraordinary measures (i.e. rapid colonization of space).
“”If [discussing renewable energy with conservatives] you deliver the message of energy freedom, energy choice, competition, national security, innovation, all of a sudden, you will have a receptive audience and they will listen to you. If you lead off with climate change, they’re not going to pay a bit of attention to anything else you say. They’ve been brainwashed for decades into believing, oh, we’re not damaging the environment…
As you can see above, fact-based debate on this is as one-sided as bringing an 8-inch atomic artillery piece to a knife fight. So climate denial inevitably involves a barrage of bad-faith misdirection tactics that do nothing to rebut the scientific consensus at issue.
Which makes more sense?
The denialist staircase
|—George Monbiot, Heat|
Global warming deniers form a sliding scale of denial which is outlined below — in general these beliefs are designed to prevent action being taken.
- Not only deny global warming, but insist the opposite is occurring, pushing the degree of denialism to the verge of the delusional.
- Simply deny global warming is happening and maintain that no action is necessary — so we don't have to change anything.
- Global warming is happening, but it’s not caused by humanity — so we don’t have to change anything.
- Global warming is happening, and it is in part caused by humanity, but mostly it's caused by solar activity — so we don't have to change anything.
- Global warming is happening, and it is in part caused by humanity, but predicting future emission levels is equivalent to astrology — so we don't have to change anything, Ehrlich!
- Global warming is caused by humanity, but it may be a good thing — so we don’t have to change anything.
- Global warming is happening, it is caused by humanity, it may be a bad thing, but [insert emotional appeal and/or false dichotomy about how doing anything about it would prevent the world's poor from improving their lives] — so we don't have to change anything.
- Global warming is happening, it is caused by humanity, it may be a bad thing, but there are still more serious crises that deserve higher priority — so we don't have to change anything.
- Global warming is happening, it is caused by humanity, it is a bad thing, but it's just human sin, so outside of worthless praying, we don't have to change anything.
- Global warming is happening, it is caused by humanity, it is a bad thing, but China and India aren't doing anything — so we don’t have to change anything.
- Global warming is happening, it is caused by humanity, it is a bad thing, and maybe China and India are willing to do something, but I've heard about this new energy source/technology that's going to completely solve the problem in 10-20 years — so we don't have to change anything.
- Global warming is happening, it is caused by humanity, it is a bad thing, but even if China and India do something it’s too late for us to do anything and it would cost us a shitload of dough — so we don’t have to change anything.
- Global warming was happening, it was caused by humanity, it is a very bad thing and previous governments could and should have done something, but it's too late now!
When debating global warming, it is wise to establish beforehand which of the opinions each debater holds, referring to the list above — otherwise you can waste a lot of time proving the wrong point. It may be similar to arguing with someone about the New World Order (NWO) as you need to find out exactly where they stand before engaging with them.
Global warming deniers have raised a number of slightly more scientific arguments which are covered below.
Many of these claims are thrown into one big denialist soup. However, the problem is that many of them are also contradictory in nature.
For example, the common talking points about it being warmer during the Medieval Warm Period and low climate sensitivity (i.e. "climate is much more stable than that") contradict each other, because the existence of a Medieval Warm Period necessitates high climate sensitivity.
Another common inconsistency lies in asserting that "temperature records and proxies are notoriously inaccurate" (always to some undecidable degree beyond the statistical error scientists already factor in), while in the next breath, suddenly
inventing presenting select 'reliable records' as evidence for whichever esoteric conclusion on global climate the individual denialist in question happens to be gunning for this time around.
In a nutshell
NASA and the Y2K bug
Steve McIntyre deduced, and NASA recently admitted, that NASA programmers had a Y2K bug in their source code that processes temperature data. This bug introduced a 0.02% change in the temperature data that has been corrected. Before this correction 1998 was listed as the hottest year recorded, but this difference was statistically non-significant with the second place year 1934; with the correction 1934 becomes the hottest year. 1934 was a period of intense drought in the United States, as it was during the Dust Bowl years in the Great Depression. The change does not affect the global temperature; it only changes the temperature data for the United States. This confuses global warming deniers, who largely do not understand that the world extends beyond the borders of the United States.
The old temperature series data for the U.S. was as follows:
With the correction it changes to:
Denialists jumped on the bandwagon in regards to this shift making many grandiose claims that it invalidates all of the data that proves this has been the hottest decade in recorded history. This is not the case; it only makes a tiny difference that does not change the decade averages or the global averages.
Glacier retreat calculations
Scientists have found DNA from ancient animals in an ice layer of Greenland, 1.9 km (1.2 miles) beneath the surface. Since this study indicates that the ice layer survived the last interglacial, it has led to speculation that the ice caps may be able to also withstand global warming. However, the main author of the study "dismissed" suggestions that his team's data indicated that sea levels would not rise to predicated levels, saying that "during the last interglacial, sea levels rose by 5-6m, but this must have come from other sources additional to the Greenland ice cap, such as Antarctic ice. I would anticipate that as the Earth warms from man-made climate change, these sources would still contribute to a rise in sea levels."
Another scientist pointed out that it may not be reasonable to extrapolate the study's results to our current situation, because the temperature changes in previous interglacials occurred at a much slower pace. Coincidentally, this article provides more evidence that the world is at least 120,000 years old, which flies in the face of creationists who claim the earth is 6000 years old.
Nature generates more CO2 than humans
While it is true that natural sources of CO2 release represent a much higher percentage of CO2 output, natural carbon "sinks" that take up that CO2 balance it out whereas humans add extra CO2, without removing any. The amount of CO2 in the atmosphere has been relatively constant for hundreds of thousands of years due to output and input being equal. What humans are doing, is burning and releasing natural carbon sinks, therefore releasing CO2 without creating additional carbon sinks, leading the net amount of CO2 to increase over time due to our involvement even though the total human output is less than natural sources.
One of the interesting things is that the natural outputs of CO2 and the human-made outputs contain different isotopes. Fossil fuel burning outputs CO2 that has less 14C and 13C than do natural sources. Using tree ring dating it can be shown that the proportion of 14C-containing CO2 in the atmosphere decreased substantially prior to the 1940s, when the largely defensive weapon of atomic bomb actually negated our ability to use that test. But 13C testing confirmed the 14C testing and showed that fossil fuel burning is the number-one contributor to the increase in the CO2 in the atmosphere.
Volcanic activity, specifically underwater volcanic activity, is often cited (usually drawing on the writings of Ian Plimer) as producing more CO2 than humans. This, however, is demonstrably false. So-called large igneous provinces, mostly lava flows of huge volume (millions of cubic kilometers) that erupt over a few million years, may be associated with rapid global warming, but none have erupted in the past five million years. Within human history, volcanic eruptions tend to have a cooling effect due to emission of sulfur aerosols.
Human activities emit 60 or more times the amount of carbon dioxide released by volcanoes each year. Large, violent eruptions may match the rate of human emissions for the few hours that they last, but they are too rare and fleeting to rival humanity’s annual emissions. Since the start of the Industrial Revolution, more than 2,000 billion metric tons of carbon dioxide have been added to the atmosphere by human activities whereas the global estimates of CO2 fell within a range of about 0.3 ± 0.15 billion metric tons of carbon dioxide per year, making human carbon dioxide emissions around 90 times larger.
Oddly enough, some denialists also point out the significant amounts of CO2 created by livestock, and somehow totally ignore that these animals are bred and kept by humans, ergo making it human-made emissions. Clearly it is (anthropogenic) burning of fossil fuels that is responsible.
A more bizarre claim was made by Tom DeWeese of the American Policy Center, namely that trees give off CO2 instead of absorbing it. He also claimed that environmentalism was the work of Communist leaders bent on destroying the freedoms of the West after the collapse of the Soviet Union, which indicates that live audio and Dunning-Kruger often go hand in hand. Scientific studies prove Global Warming can not be caused by natural forces alone.
Even if it was not the cause that humans are causing global warming, this is absolutely not a reason to not do something about it. It would be just as dumb of a decision as doing nothing about an incoming earthquake, hurricane, typhoon or volcano eruption simply because those aren't caused by humans.
CO2 levels lag behind temperature increases
There have been several major changes in the Earth's climate over its 4.5-billion year history. These have included spectacular effects such as the snowball earth and periods of intense global warming. These periods of warming and cooling all have a range of causes mostly involving positive feedback loops, such as ice reflecting the sun back to space causing more ice, reflecting more sun, and Milankovitch cycles, variations in Earth's orbit that have an effect on climate. The warming had similar positive feedback loops, which initially could have been caused by one of many factors but eventually the warming increased the levels of CO2 which then caused even more warming. The fact that CO2 level increases have not been responsible for the start of 100 percent of all global warming events on the planet does not negate the fact that CO2 in the atmosphere does cause warming.
In the case of warming, the lag between temperature and CO2 is explained as follows: as ocean temperatures rise, oceans release CO2 into the atmosphere. In turn, this release amplifies the warming trend, leading to yet more CO2 being released. In other words, increasing CO2 levels become both the cause and effect of further warming.
- The 800-year lag displayed is about the time required to flush out the deep ocean through natural ocean currents while warmings take about 5000 years to be complete.
- The Earth's orbital cycles triggered warming in the Arctic causing large amounts of ice to melt, flooding the oceans with fresh water. This influx of fresh water then disrupted ocean current circulation, in turn causing a seesawing of heat between the hemispheres.
- The Southern Hemisphere and its oceans warmed first, starting about 18,000 years ago. As the Southern Ocean warms, the solubility of CO2 in water falls. This causes the oceans to give up more CO2, releasing it into the atmosphere, which in turn caused the entire planet to warm via the increased greenhouse effect.
- Basically, the study concluded that CO2 lags and leads. In the Southern Hemisphere, the temperature rise happened first (CO2 lagged), whereas in the Northern Hemisphere, the CO2 increase was first. This is because of the above described points.
- Overall, more than 90% of the glacial-interglacial warming occurs after the atmospheric CO2 increase. Indeed, given that CO2 does not lag the current warming is one more piece of evidence demonstrating that established natural cycles are not the cause of the warming.
Water vapour is a more important greenhouse gas
Water vapour is one of the most potent greenhouse gases in the Earth's atmosphere and accounts for a substantial portion of the greenhouse effect that raises the Earth's temperature from an inhospitable 19 degrees below zero to a more temperate 16 degrees above zero. Global warming denialists have used this to claim that carbon dioxide (CO2) is an unimportant gas in the greenhouse effect — and this can be coupled with the fact that burning fossil fuels (oxidation) results in the release of water vapour in addition to carbon dioxide.
However, this argument that CO2 is not the cause of global warming misses (possibly intentionally) several key facts. First, water vapour is often saturated in the atmosphere. At high altitudes, where the temperature is low, water vapour cools and condenses to form clouds, and if the water droplets are big enough, this leads to rain. The amount of water vapour, therefore, is largely dependent on the temperature. Adding water to the atmosphere may alter weather patterns but its concentration does not differ on the scales considered by climate scientists. As it is removed from the atmosphere on a fast time scale, it can cause short lived but extreme changes in temperature, and so is the cause of much freak, but short-term, weather. Carbon dioxide on the other hand has a much longer life-time in the atmosphere and its concentration is not capped by saturation in the atmosphere. This makes the effect that CO2 has on the Earth's climate a considerable force.
It has been hotter in the past so it is just cyclical
While it is true that there have been cyclical patterns of temperature changes throughout our planet's history, this does not mean that causes are unknown, unknowable, or all the same. The application of the scientific method is great for working out cause/effect relationships. Scientists have managed to link several warming and cooling cycles in the geologic history to specific causes. They have also shown that the modern warming is due to the added output of humans burning fossil fuels and destroying carbon sinks. In addition, the current climate change is happening fast — over a period of decades rather than millennia. Past natural climatic patterns that were destructive were associated with cool periods while the projected future catastrophe from AGW is going to be associated with warming; this makes man-made climate change much worse than naturally occurring climate change.
The existence of previous warming cycles does not negate the seriousness of the current one. These previous cycles destroyed a great deal of life on the planet, and if similar effects occurred today they could potentially destroy all of human civilization, along with the humanity that created it. This does mean that the earth itself will survive, but no denialist would be around to gloat.
Global warming has more to do with the Sun than the Earth
Changes in the Sun have not been responsible for recent climatic trends; there has not been any significant change in the total energy output of the sun since we have started measuring it, and no changes in the sun or sun phenomena correlate with increased temperatures. Over the last 35 years the sun has shown a cooling trend, meanwhile global temperatures continue to rise.
One thing that can change is small perturbations in the orbit of the Earth that draw the planet closer to or further from the sun. These perturbations might be linked to the start of several of the major climate changes in the geologic history of the Earth. Nonetheless, the actual change in temperature due to these orbital changes is small and the large-scale changes are due to feedback loops localized to Earth pushing things in one direction or another.
There is no evidence that such an orbital shift is happening now, but even if it has, it can only explain a very small percentage of the increase in global temperature. This issue was also a point of contention in the Soon and Baliunas controversy.
It must be the sun because other planets are warming too
Many of the planets and moons (and a certain dwarf planet) in our solar system are big enough and geologically active enough to have both an atmosphere and a climate. In any given system there will be some planets increasing in temperature and some decreasing in temperature. This is due to changes in the localized climate, just as it is with Earth. The causes are different for each planet and have little to no bearing on each other.
Even if the sun does have a role, it is not likely that our own activities are helping the situation. It would actually be even more incentive to temper our works, because anthropogenic activity combined with solar activity obviously equals even higher rates of warming.
Here is a brief description of each planet said to be experiencing global warming used by denialists to suggest that global warming is caused by the sun:
- Mars: Mars has an elliptical orbit with high eccentricity. The orbit of the planet contributes greater changes to Martian climate than to Earth’s climate because it’s orbit is more extreme and eccentric than earth’s. Furthermore, Mars has a very thin atmosphere which makes it much more susceptible to climate changes than Earth. Therefore, even if Mars is experiencing global warming, it does not prove the sun is the culprit behind climate change. This is also because there is little evidence that the Martian climate is warming. Martian climate is primarily driven by dust and albedo,[note 2] not solar variations. The main piece of evidence for Martian warming is Fenton 2007 which compares 2 snapshots of Martian surface taken by orbiters 22 years apart (1977 and 1999).
Urban heat islands
This point contends that weather station readings are affected by their proximity to cities, or "urban heat islands." See the article on Patrick Michaels, a notable proponent of this argument, for a treatment of this point.
Hey look! There's been no global warming since 1998
One of the most popular claims made against climate science is that there has been "no global warming since 1998," or even that there has been a pattern of "global cooling" since that year. Denialists who have made this argument include Tim Ball, Nigel Lawson, Fred Singer, Andrew Bolt and Christopher Monckton. The origins of this argument are unclear; perhaps it might have originated in a column by Bob Carter which appeared the Daily Telegraph in 2006.
This argument fails for several reasons: it only takes into account the satellite measurements (UAH and RSS), which doesn't measure directly the surface temperatures. Not only are these satellites run by known deniers John Christy and Roy Spencer, but they are funded in part by Exxon. No conflict of interest there! By contrast, both scientifically accepted surface temperature datasets (GISS and HATCET4) are only funded by government sources, and they show that the warming not only continues, but is accelerating in lock and step with the CO2 emissions. Most importantly, this is one of the finest examples of cherry picking since deniers only look at the data sets that match the conclusions they want to see. Classic climate denialism demands that average global temperature measurements must be taken from the peak of the hottest year and measured to the point trough of the coolest year. If the denialists ever picked years either side of 1998 as their start point, the argument would sink faster than the Titanic. This is because globally, 1998 was a record breaking hot year due to a very strong El Nino. Additionally, another strong El Nino in 2015-16 caused temperatures to soar far past those seen in 1998, so they now have to ignore that time has been passing since 2014 as even their beloved RSS shows a record hot year.
Using anecdotal evidence
Using arguments such as "Wow, it's really cold today! Global warming, my ass!" or "See! It's snowing in Atlanta for the first time in years!" to argue that "global warming" misuses numerical data, since even without global warming, there are fluctuations in local temperatures. Global warming refers to an overall average increase in temperatures of air and water. Additionally, global warming will temporarily result in some local areas that are cooler, despite the global average increasing.
Strangely enough, this is a common argument used by Fox News and other right-wing organizations who often claim scientists are only using anecdotes of hot weather as proof of global warming when the exact opposite is true. Even more strange, when someone asks where the global warming is because it's snowing where they live, and someone else responds back with "It's 75°F and sunny here, and I'm north of you and up in the mountains" there is often a lingering silence. Apparently anecdotal evidence isn't allowed to work both ways.
Claiming there is no consensus in respect of global warming
Global warming denialists often try to claim that there is no scientific consensus, despite the fact that the IPCC — the main international body associated with investigating the phenomenon — says:
“”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... There is very high confidence that the net effect of human activities since 1750 has been one of warming.
Despite this assertion, denialists have attempted to use such methods as the discredited Oregon Petition in an effort to prove their case.
A 2004 study by Naomi Oreskes reviewed over 900 peer-reviewed papers and found none that dissented from the consensus. Criticism of the study has been withdrawn but continues to be repeated in denialist circles. For instance, Lawrence Solomon has claimed that Bennie Peiser, the British scientist who made the criticism, never actually withdrew it and Wikipedia is "censoring" him.
97% scientists do not agree on climate change. The study was “unscientific”
Communicating the expert consensus is very important in terms of increasing public awareness of any scientific topic. So it's not so surprising that Cook et al. (2013) and its 97% consensus result have been the subject of extensive denial among the usual climate denial members.[note 3]
Antarctic sea ice is increasing
Many deniers will point to record setting Antarctic sea ice as proof that the warming has stopped, but they get quite uncomfortable when you point out the fact that Arctic sea ice and total global sea ice are at record lows, and continue to decrease at alarming rates. In fact, there is a scientific explanation for the record Antarctic sea ice. As ice on the land melts, it flows into the ocean, reducing the salinity of the ocean, and in turn raising the freezing point of the water.
It is precisely because of the fact that Antarctica is melting that sea ice is growing, and scientists have been predicting this all along, not only because of the melting on land, but also because AGW causes the wind to increase, blowing more snow into the ocean, and further creating a snowfall effect, but reducing the salinity further.  Scientists say that this effect is only temporary, and that when the snow on land is reduced by wind and melt to a certain tipping point, the melting of the sea ice will accelerate, which it has done since Antarctic sea ice is now at record lows. 
Scientists noticed that historically, the world had been heading towards an ice age.[note 4] A minority of scientists in the 1970s and earlier also predicted that the pollution would have cooling effect due to increased cloud cover from factories and other emissions. This actually is a thing and does throw a bit of a curveball into the models and appropriate course of action. For example, after 9/11 global air traffic more or less shut down, and the lack of contrails led to the discovery that airplane contrails act to stabilize air temperature throughout the day. The real world is complicated,[citation NOT needed] and people use science to discover how it works. As such, scientific knowledge marches ever forward, and obviously the world has been warming. But the few works published have been enough for "climate skeptics" to strip mine for quotes.
Trotting out the global cooling trope is sometimes called the ice age fallacy.
Anthony Watts vs NOAA
Climategate was a manufactroversy in which documents were leaked that seemed to indicate a conspiracy to promote global warming among climate scientists... if you didn't understand the language of climate science.
“”What I’m suggesting is we have a sort of an eco-evangelical hysteria going on and it leads me to almost wonder if we are becoming a nation of environmental hypochondriacs that are willing to use the power of the state to impose enormous restrictions on the rights and the comforts of, and incomes of individuals who serve essentially a paranoia, a phobia, that has very little fact evidence in fact. Now these are observations that are popular to make because right now it's almost taken as an article of faith that this crisis is real. Let me say I take it as an article of faith if the Lord God almighty made the heavens and the Earth, and He made them to His satisfaction and it is quite pretentious of we little weaklings here on earth to think that, that we are going to destroy God’s creation.
|—Dick Armey (R-TX), on global warming|
In addition to snarling falsehoods, global warming deniers also like to deride their opponents. While there's nothing wrong with shit-slinging, two terms used by global warming deniers are used in order to imply falsehoods or alarmism.
"CAGW", for "catastrophic anthropogenic global warming", is a snarl word (or snarl acronym) that global warming denialists use for the established science of climate change. A Google Scholar search indicates that the term is never used in the scientific literature on climate.
It's not clear just when or how the denialists adopted CAGW over from the acronym AGW (anthropogenic global warming) used by normal folk. The term was used in blog comments at the New York Times and ScienceBlogs as early as 2008, and is likely to have been used earlier. By around 2011 CAGW had become commonplace in denialist blogs such as those of Anthony Watts or Judith Curry, and over the next year or two essentially replaced AGW in such esteemed venues. Despite the qualifier, denialists apply the term indiscriminately to anything approximating the mainstream scientific view on climate, regardless of whether or not "catastrophic" outcomes are implied.
As for motivation, it's an attempt to move the goalposts. Denialists realized they had lost the argument over plain old "anthropogenic global warming" — the basic physics of the problem have been known since the 19th century, so that rejecting AGW outright paints oneself as a loon. Adding "catastrophic" gives plenty of wiggle room for denialism. Sea level rises a foot? Just a few Pacific Islanders losing everything; no catastrophe. Sea level rises a few more feet? The Philippines get flooded out and we lose coastal cities like London and New York. But with a few trillion dollars we can move them inland; no catastrophe. And so on.
Originally, before the consensus developed, the term was value-neutral. Those who argued for global warming theory were nicknamed "warmists" and those against were called "coolists" or "coldists." Post-consensus, the term warmism is now used in a derogatory sense, often as in "the warmist cult," "the religion of warmism," or "the warmistas." Al Gore is often considered the high priest of the warmist cult. The term "coolist" has mostly fallen out of use, being largely replaced by "skeptic" (for journalists who want to seem balanced) or "denier" (for those who prefer to call a spade a spade). The "warmist" versus "denier" terminology is akin to "evilutionist" or Darwinist versus creationist in the debate over evolution, except the former pair tends to be used with more seriousness than the latter.
A third but smaller breed has positioned itself between the "warmist/denier" dichotomy — the "lukewarmer." Unlike the other two labels, however, "lukewarmer" is often used as an un-ironic self-descriptive term. Lukewarmers tend to eschew outright denying climate science in favor of systematically low-balling IPCC estimates (see also Bjorn Lomborg).
The effects of global warming will be many, varied, and almost wholly negative. Pretending global warming is not happening will not make it go away.[citation NOT needed]
“”The danger of global warming is as yet unseen, but real enough for us to make changes and sacrifices, so that we do not live at the expense of future generations. Our ability to come together to stop or limit damage to the world's environment will be perhaps the greatest test of how far we can act as a world community. No one should underestimate the imagination that will be required, nor the scientific effort, nor the unprecedented co-operation we shall have to show. We shall need statesmanship of a rare order.
|—Margaret Thatcher, 1990|
- A rise in sea level: The most conservative prediction of sea level rise presently predicted is 9–88 cm (3.5–34.6 inches). This small rise would be enough cause significant disruption to coastal communities. Some places, such as Kiribati, are already feeling these effects.
- There is a possibility, however, that the whole Greenland ice sheet would melt leading to a global rise of 7 m (23 ft). There is even a possibility that the West Antarctic ice sheet could melt raising sea levels by a further six meters (20 feet). Although the rest of the Antarctic is considered to be stable, if the entire Antarctic were to melt, this would raise sea levels by 62 meters (203 feet). Although this isn't enough to turn the Earth into Waterworld, it's more than enough of a rise to render every major coastal city on the planet uninhabitable. Want a visualization? Say goodbye to Miami, NYC, New Orleans, Venice, Tokyo, Mumbai, and Shanghai.
- In addition to the rises in sea level caused by melting glaciers, sea level would also rise as a consequence of the thermal expansion of the warmer water.
- More active weather systems: More energy in the atmosphere will lead to more active weather systems, with more frequent and more violent storms. More severe weather events such as storms, floods, heatwaves and hurricanes will be the result. Hurricanes will become more severe and long-lived as the Earth warms, specifically due to the warming of the oceans. It is warm sea surface temperatures above 26 °C that are required for hurricanes to form, and to be able to sustain themselves because the heat that fuels hurricanes is from the latent heat of condensation.
- Disturbed rainfall patterns: Rainfall patterns will be significantly disrupted with floods in some places and droughts in others. Regions closest to the equator (central Africa, Latin America, India, Southeast Asia, etc.) are more likely to face extreme vulnerability.
- Acidification of the oceans: The ocean has a limited capacity to dissolve carbon dioxide before it ceases to absorb any more (which would thus lead to further warming). The dissolved CO2 can react with the water forming carbonic acid and H+ ions, causing it to become more acidic (lower pH). This would cause great damage to fish stocks. It also reduces the amount of carbonate dissolved in the water, which shellfish depend on for their shells. The acidity (pH) of the ocean is currently ~8.0, slightly alkaline, and the earliest signs of increasing acidity (and temperature) is coral bleaching, where the photosynthetic mutualists in the coral die leading to the collapse of the coral reefs which are often described as the 'rainforests of the sea' due to the level of biodiversity.
- Tipping points/feedback loops: There are many possible tipping points and feedback loops. For instance, if global warming causes the northern permafrost to melt this will release vast amounts of methane which will make the problem much worse. It is thought that a similar release of frozen methane hydrate from arctic ocean floors resulted in a runaway greenhouse effect at the end of the Permian period, which may have been a leading cause of the Permian mass extinction.
- Spread of tropical diseases: As northern latitudes become warmer previously-rare tropical diseases will gain a foothold in more northern latitudes. The World Health Organization has identified more than 30 new or resurgent diseases in the last three decades, the sort of explosion some experts say has not happened since the Industrial Revolution brought masses of people together in cities. Another report made by WHO in 2000 found that warming had caused malaria to spread from three districts in western Kenya to 13 and led to epidemics of the disease in Rwanda and Tanzania. However, the relationship may not always be so simple — one study demonstrated that warmer temperatures may increase the number of malarial parasites but also decrease the rate at which they become infectious. In Sweden, cases of tick-borne encephalitis have risen in direct correlation to warmer winters. Asian tiger mosquitoes, the type that carry dengue fever, have been reported recently as far north as the Netherlands. Cholera, which thrives in warmer water, appeared in the newly warmed waters of South America in 1991 for the first time in the 20th century. "It swept from Peru across the continent and into Mexico, killing more than 10,000 people." Once confined to land near the equator, West Nile Virus is now found as far north as Canada. Seven years ago, West Nile virus had never been seen in North America; today, it has "infected more than 21,000 people in the United States and Canada and killed more than 800." This also doesn't affect just humans. Introduced mosquitoes have also spread their wrath onto vulnerable and highly endangered native birds in Hawaii, which climate change allows those little pieces of disease to travel to higher elevations.
- Disruption of ocean currents: The disruption of ocean currents could shut down the Gulf Stream with unpredictable consequences. Melting of the ice sheets could result in a weakening of the thermohaline circulation as the Arctic and Antarctic Ocean's warm, decreasing the temperature difference and thus flow of heat as it's redistributed from the equatorial regions to the high latitudes. It is believed that the collapse of the ocean currents may lead to extreme levels of ocean anoxia, because the currents are essential for carrying dissolved oxygen below 500 meters of depth. This may possibly mean wiping out the overwhelming majority of multi-cellular ocean life.
- Habitat loss/change faster than animals can adapt: Temperature zones will move north and south too quickly for animals to follow or adapt to new habitats. The most extreme case is that of arctic habitats which will leave animals such as polar bears with no place to go. In 2007 Indonesia's environment minister has announced that scientific studies estimate about 2,000 of the country's lush tropical islands could disappear by 2030. Deserts have already started increase in size toward higher latitudes, and are projected to increase in size by 10%-30% by the end of the 21st century.
- Climate exodus: Okay hard right-wingers, you can try suppressing immigration or deny the existence of climate change but you can't have both. One major issue is the massive flood of migrants that will happen in coming decades as a result of increasing uninhabitability. It will likely spread like a wave, first affecting nations near the equator and slowly moving further away. It will start with poorer countries in the region, but eventually, wealthier countries in the region will collapse due to either the migrant crisis or temperatures getting too hot for technology to balance it out anymore. As the crisis spreads, extremism will explode as opinions on what to do contradict each other. Some major powers may go crazy and begin performing border massacres and invasions, in an attempt to stop the wave of migrants and impending economic collapse as a result of the collapse of cheap labor and the potential rise of autarky. Internal migration will likely become an issue in some nations as parts such as the American Southwest begin to lose inhabitability to desertification. Hopefully, it'll stop around this point, but it may keep going as a trend moves humanity further and further from the equator. Extremist militias would likely dominate the depopulated former nations. At this rate, the trend will likely start with Southeast Asia and central Africa.
- Loss of mountain glaciers: Mountain glaciers act as natural reservoirs, releasing winter snow as meltwater during the summer. Global warming will disrupt this system in two ways:
- Social effects: Global warming and the retreat of Arctic ice is already causing social repercussions for various nations. A good example of this is the battle for control of Hans Island. Hans Island is a barren, uninhabited chunk of rock fully two square kilometres in surface area that is bisected by the dividing line between the respective territories of Greenland and Canada. In the past the sovereignty of this insignificant island was undisputed since it was economically worthless, but with summer pack ice ever retreating it may shortly be the case that control of Hans Island grants access to huge, untapped hydrocarbon deposits as well as control of shipping through the Nares Strait.
- There has been considerable diplomatic tension between Canada and Denmark (who represent the interests of Greenland in all international affairs) over the sovereignty of the island. Both nations have made expeditions to the island to plant their respective flags, and assert their claim to the island. Like all good controversial issues, the battle for Hans Island has spawned a large number of parody sites on the Internet.
- Agricultural effects: Drought could have major influence on agriculture as could flooding or massive change in temperature. This could have major economic impact in developed countries and threaten food supplies in poor nations. Effects on agriculture can be positive or negative but overall outcomes of agricultural activity become less predictable.
- And, if you've been sleeping through this list, serious damage to coffee, tea and chocolate stocks.
Not all of these consequences are certain, and some may be mitigated. For example, whilst global warming might tend to promote the spread of tropical diseases, advances in medicine or control measures (insect spraying, swamp draining) could well counteract this, as has already happened during the industrial era for a number of previously common diseases.
Equally though, there will probably be many unanticipated additional — probably negative — consequences.
If climate change doesn't sound so bad, consider that we've spent the past few hundred years building cities in places that don't flood, farms in places with enough water, and ice hotels in places with, well, ice. There is an awful lot of money and human endeavor relying on the weather staying just the way it is.
“”Global warming, like globalization, is good for the economy, and therefore humanity:
|—Chairman of the Federal Reserve, Ben Bernanke ()|
It has been hypothesized that the added heat and CO2 from global warming would increase plant growth, thus creating a "greener" Earth. However, a 17-year experiment on California flowers and grasslands found that plants growing with extra heat or CO2 did not grow more, did not remove pollution and did not store more of it in the soil. Only extra nitrogen made plants greener. It has also been found that the increased plant growth will not likely be sustained, and that the increased CO2 also causes decreases in some important nutrients, such as selenium and zinc.
It should also be noted that global average temperatures were higher during the Jurassic period than they are today. This does not, unfortunately, mean that global warming will bring back the extinct dinosaurs. The currently living ones such as chickens, on the other hand, may evolve to fill the new niches. So if you want a world where your puny children are mere morsels for the almighty Cockasaurus Rex, trade in that SUV for a hummer.
There are some positive impacts that deniers like to use such as longer growing seasons in Canada and northern Europe, but they never bring up the fact that even really bad things have some positives. What's important is not really if there are any positives, but rather, if the positives outweigh the negatives. When economists, scientists, and engineers perform cost-benefit analysis of global warming, the negatives outweigh the positives 25 to 1. When you bring this fact up with deniers, they quickly change the subject. 
Global warming wager
The "global warming wager" is an application of the precautionary principle to the anthropogenic theory of global warming (some have drawn with Pascal's wager). That is, even if there is uncertainty that global warming is happening, we have to prepare for the worst case scenario anyway:
This argument is unlikely to advance a conversation as Pascal's wager has several known logical issues that render it useless as a decision-making tool in the face of uncertainty. However, in this case, the impact of human-generated pollution on the Earth's temperature has been and is being directly observed. Arguments against the likelihood of negative consequences can be met directly with evidence.
“”Plot idea: 97% of the world's scientists contrive an environmental crisis, but are exposed by a plucky band of billionaires & oil companies.
The "Global Warming Conspiracy Theory" (GWCT) refers to the questionable ideas bandied about by global warming denialists that global warming either isn't happening or is being over-hyped by a group of people who feel that they have some advantage to gain by promoting the evidence for global warming, apparently never having considered how much Oil Companies gain from denying the evidence for Global Warming.
Besides the general nonsensical nature of many of these theories, they generally fail to answer how the conspiracy reaches back to John Tyndall's discovery of the greenhouse effect in 1859 (perhaps Al Gore invented a time machine after he was done with the Internet).
“”So-called global warming is just a secret ploy by wacko tree-huggers to make America energy-independent, clean our air and water, improve fuel-efficiency of our vehicles, kick-start 21st century industries, and make our cities safer and more livable. Don’t let them get away with it!
As is typical of many conspiracy theories, there is not one theory but several contradictory ones. Some of the ones identified here are now a little out of date, and no doubt conspiracy theorists have now invented some other tortured reasons for people backing the "conspiracy." Because of the multiplicity of contradictory theories, it is a good idea to get a global warming denialist to explicitly state which particular "theory" they are backing.
A genealogy of climate change conspiracy theories can be found at the International Journal of Inactivism.
The following are some of the many specific conspiracies identified regarding global warming. Note that this lists conspiracies rather than flat-out denials, though they often go in tandem.
- United Nations world-conquering scheme: Apparently, an individual named "Maurice Strong" is behind an attempt to use the United Nations and its Framework Convention on Global Climate Change to… well… take over either the world or the United States. He is apparently assisted in this by World Economic Forum, the Club of Rome, the Aspen Institute, the Fabian Society, and Communist China — he is, however, opposed by none other than The Dalai Lama! Christopher Monckton loves this one.
- NWO scheme: It's an attempt by scientists, politicians and environmentalists to take over the world. According to William M. Gray, they wish to find "a political cause that would enable them to organize, propagandize, force conformity and exercise political influence.'" Apparently Al Gore has something to do with it. Muahahaha!
- Jacques Chirac scheme: It's an attempt by former French President Jacques Chirac and the secret Bilderberg Group to use the Kyoto Accords to take over the world.
- Climate science funding scheme: It's all a hoax invented by all the world's climate scientists to get funding. The "evil" scientists have managed to fool the UN, the European Union, and the entire world. This angle is also rather ironic considering that a sinecure at a denialist think tank can easily pay better than an actual post as a climatology professor.
- Green energy scheme: All climate scientists obviously own stock in green and renewable energy companies and they're pushing the theory to inflate their retirement funds and the green energy companies will make out like bandits. Not.
- Anti-Africa scheme: It's a plot by those nasty environmentalists who want to prevent Africa developing a carbon economy. Alternatively, it's a plot by environmentalists who want to promote a carbon economy in Africa while damaging the USA's industrial output. Two "theories" for the price of one!
- Anti-globalist scheme: This one suggests that it's associated with the anti-globalisation movement and it's an attempt to cripple the world economy. But how one can accept international treaties while opposing globalization is never explained.
- Pro-nuclear scheme: According to this "theory," it's all about an attempt by Margaret Thatcher, and presumably her successors, to make the people of the world accept non-CO2-producing nuclear power. It's not exactly clear what Phase 2 is, but Phase 3 seems to be "profit." This was promoted in the film The Great Global Warming Swindle. As it becomes clear that "politically correct" renewable energy sources such as wind and ground-based solar are unable to meet the needs of civilisation, expect this one to be uttered more often by fossil fuel industry opponents. It is noteworthy that the UK nuclear power industry has been handed over to the French! (see Jacques Chirac above)
- Socialist scheme: This theory claims that a carbon emissions tax (as proposed again by Al Gore, OMG!) would allow the United States government to gain substantial influence over industry (which, after the way they've managed to facilitate a global recession, wouldn't be a bad thing, if the recession wasn't mostly caused by problems in the housing market, of course). Exactly why Al Gore would benefit from the US government controlling corporations is unclear. Furthermore, with all the investment the government is presently being forced to make in industry, it may end up controlling a lot of it whether it has a carbon tax or not.
- Commie scheme: Supported by, among others, Frederick Seitz and Eric S. Raymond, this claim is that global warming was a Soviet plot meant to undermine capitalism. Terms like "memetic weapon" and "leftover KGB psyops" have been thrown around, making this one of the loonier approaches.
- Eugenics and/or depopulation scheme: This brand of the conspiracy theory states that global warming is a front for the implementation of a worldwide eugenics program or a scheme to depopulate the planet and kill off the "useless eaters." Quotes from nutty hard greens (Pentti Linkola is a perennial favorite) often come in handy for "proving" this. A particularly amusing if little-known variant of this conspiracy theory posits that the depopulation plan was initiated by the anthropologist Margaret Mead at a 1975 conference on overpopulation. This theory is more popular in the conspiracist pro-life circles due to its connection with the issue of abortion and it also makes for some good red-baiting material due to China's one-child policy, and you don't want to end up like those dirty Reds now do you?
- Fake news scheme: This scheme most notably surfaced with Rush Limbaugh and Alex Jones casting doubt on forecasts of extreme weather events, in particular Hurricane Irma of 2017. Limbaugh's gambit is that the media benefits from increased advertising revenue from people watching extreme weather events on TV and retailers benefit from increased sales from extreme weather preparation, therefore it's fake news and part of the the climate-change conspiracy.
The real conspiracy
There actually is a conspiracy surrounding climate change, and it's not what you'll hear from most conspiracy theorists: between 2003 and 2010, more than $7 billion were spent by conservative billionaires to fund anti-AGW organizations such as the Heritage Foundation, the Heartland Institute, and the Competitive Enterprise Institute. Follow the money, indeed.
There are many entrenched interests who benefit from the current energy infrastructure of our modern civilization. Commonly mentioned "villains" are oil companies (as well as the complicit politicians they lobby) who would stand to lose a lot of money if action were taken to reduce the amount of carbon dioxide dumped into the atmosphere, as this would imply a reduction in the use of fossil fuels such as oil. But consumers are "the other half" of the same problem and (for example) US drivers have been very resistant to an increase in gasoline taxation.
Exxon (later ExxonMobil) has known since at least 1977 that global warming from fossil fuels could be an issue. By 1981, Exxon was "already factoring climate change into decisions about new fossil fuel extraction," but was simultaneously promoting coal in 1981 TV advertisements. In 1995, there was an internal Exxon report that unequivocally stated that "burning the companies' products was causing climate change and that the relevant science 'is well established and cannot be denied.'"
Consequently by way of coverup, corporate interests have spent a vast amount of cash in an effort to discredit the science behind man-made global warming, and encourage global warming denialism. ExxonMobil has been one of the prime movers and Greenpeace reports have stated:
“”ExxonMobil's campaign to fund "think tanks" and organizations that spread misinformation about the science and policies of global warming is now widely known. The company’s multimillion dollar campaign has undoubtedly contributed to public confusion and government inaction on global warming over the past decade."
Greenpeace is still monitoring ExxonMobil's attempts to distort public opinion in this area as can be seen in their website exxonsecrets dedicated to exposing the company's activities.
The disinformation campaign is similar to that embarked on by the tobacco companies who wished to persuade people that cigarettes were healthy, and the campaigns carried out by the oil companies when they wished to continue adding lead to petrol. Indeed, the similarity between not only the techniques used by denialists to defend smoking and claiming that acid rain and global warming is either natural/not a huge problem/too expensive to fix, but also the overlap and interconnection in the cast of experts for hire trotted out was the core argument in the book Merchants of Doubt.
What about that ozone thing?
Some members of the public get confused between ozone layer depletion and global warming — both involve some gases that somehow influence the already arcane dynamics of the atmosphere, and both are associated with dire consequences if we do not change our comfy lifestyle. There is a slight connection: Both ozone (O3) as well as the ozone killing chlorofluorocarbons (CFCs) act as greenhouse gases, but on a smaller scale than the usual suspects carbon dioxide (CO2) and methane (CH4).
However, they are largely separate issues: ozone layer depletion means that we all die because the ozone layer vanishes and the surface of Earth is bombarded with ultraviolet solar radiation, and global warming means that we face incredible hardship because the temperatures on earth rise too quickly for the ecosystems to adapt and the entire biosphere collapses.
In a nutshell
So, we can do this two ways: suck it up and take the necessary steps now to mitigate the expected damage to human civilization, or wait another few decades debating PRATTs while millions — potentially billions — of people die around us.
- CO2 is Green
- Doctors for Disaster Preparedness
- Energy crisis
- Evil Liberal Science Conspiracy
- Tim Flannery
- Global warming denial Bingo
- Gore's Law
- The Great Global Warming Swindle, denialist propaganda film
- James Hansen
- Greta Thunberg
- Kyoto Protocol
- Michael Mann
- Oregon Petition
- Renewable energy
- Global warming denialist webshites
- See also Category:Global_warming_denialists.
- Former Australian Prime Minister Tony Abbott
- Buzz Aldrin
- American Government: Institutions and Policies (a textbook heavily criticised for its stance on global warming)
- Tim Ball
- Mike Bara
- E. Calvin Beisner
- Competitive Enterprise Institute
- Michael Crichton
- Judith Curry
- Anyone taking Ethical Oil seriously
- Family Research Council (we don't get it, either)
- Freeman Dyson
- John Everett
- Nigel Farage
- Heartland Institute
- Former Australian Prime Minister John Howard
- David Icke
- U.S. Senator James Inhofe
- Institute of Public Affairs
- International Climate Science Coalition
- Alex Jones
- Paul Joseph Watson
- Rush Limbaugh
- Richard Lindzen
- Ross McKitrick
- Steve McIntyre
- Patrick Michaels
- Steve Milloy
- Christopher Monckton
- Marc Morano
- Lubos Motl
- Joel Myers, the founder and CEO of
- Former British environmental secretary Owen Paterson
- Ron Paul
- Ian Plimer
- Dennis Prager, as well as his propaganda outlet PragerU
- Scott Pruitt, former administrator of the U.S. EPA
- Russian President Vladimir Putin
- Eric S. Raymond
- Salem Radio Network
- Frederick Seitz
- S. Fred Singer
- Roy Spencer
- Philip Stott
- U.S. President Donald Trump
- Alan Watt
- Anthony Watts
Want to read this in another language?
- What's really warming the world? The evidence is put into pretty graphs right in front of you. Shame that it has an overdose of scrolljacking and animation.
- NASA’s Climate website
- The 1847* lecture that predicted human-induced climate change, The Guardian (*: 1847, as in halfway through James K. Polk's presidency)
- NASA Data
- NOAA data
- National Academies of Science reports
- The Discovery of Global Warming, American Institute for Physics
- Royal Society's Summary of the Science and Policy Reports and Statements
- New evidence on Antarctic warming
- Open Climate Science 101, University of Chicago
- Deep Climate, coverage of climate issues and often features original research by noted denialist debunker John Mashey
- RealClimate, and its wiki
- World Meteorological Organization
- Evidence for Climate Change is Overwhelming, RAND Corporation
- Four Ways to Look at Global Carbon Footprints, National Geographic
- Which countries are decarbonizing the fastest?, Vox
- A Statistically Representative Climate Change Debate (feat. Bill Nye)
- Rear Admiral David W. Titley: I Was Formerly a Climate Skeptic
- Armstrong & Miller on Climate Change
- Blue Man Group on Global Warming
- He's a Climate Change Denier
Combating global warming denial
- What climate scientists should talk about: their personal stories, Skeptical Science (See also 97 Hours of Consensus and its denialist PRATT list)
- Skeptical Science, another guide to denialist PRATTs handily organized by "difficulty level" of the science.
- How to talk to a global warming denialist, Ill-Considered
- Other ScienceBlogs with regular AGW coverage: Deltoid, Stoat
- Interesting infographic comparison of debate points by both sides of the argument
- Clearing Up the Climate Debate, 14-part series at The Conversation
- This is the difference between weather and climate change (feat. Neil deGrasse Tyson)
- Did climate deniers just admit they don’t know what they’re talking about?, Bulletin of the Atomic Scientists
- How Newsweek's 'global cooling' story got its legs - on how a 9-paragraph article in a 1975 issue of Newsweek armed denialists with bullshit arguments ever since.
- Positives and Negatives, Skeptical Science
- By all means question climate policies. But facts are facts, The Economist
- Shattering Myths to Help the Climate, The New York Times
- Responses to the most common arguments used to deny Global Warming, Grist
Ending global warming
- Pew Center on Global Climate Change
- Tackling climate change with technology, BBC (a very brief overview of the pros and cons of technology that could be used to tackle climate change)
- IEA Shows How to Radically Reduce CO2, Climate Central
- Warming World: Impacts by Degree, National Research Council
- Climate Change in the US: Costs of Inaction, Union of Concerned Scientists
- However, based on Antarctic ice core data, changes in CO2 follow changes in temperatures by about 600 to 1000 years. This has led some to (falsely) conclude that CO2 simply cannot be responsible for current global warming.
- A good example of how dust affects Mars climate: in 2007, Mars suffered a titanic dust storm that engulfed the entire planet. The dust storm contributed to a temporary warming effect around Mars, raising the temperature of the atmosphere by around 20-30°C. Interestingly, whereas the atmosphere of the planet heated up, the surface of the planet cooled down because it received much less solar heat.
- See also:
- Technically speaking we are still in one as we still have permanent polar ice caps, for now, but towards the type of ice age where most of the world looks like Alaska.
- Missionary from Toronto winning converts — on climate change, University of Toronto
- Our position on climate change
- Black carbon ranks as second-biggest human cause of global warming, Washington Post
- The Greenhouse Effect, UC San Diego
- What are greenhouse gases?, NOAA Climatic Data Center
- Greenhouse effect: In the laboratory, Science Museum London
- Greenhouse Gases, Climate Change, and Energy, Energy Information Administration
- Global warming, Encyclopedia of Earth
- Summary for Policymakers, IPCC Fourth Assessment Report (Working Group I: The Physical Science Basis)
- Temperature Variations in Past Centuries and the so-called "Hockey Stick", RealClimate
- NRC Exonerates "Hockey Stick" Graph, Ending "Mann-Hunt" by Two Canadian Skeptics, DeSmog Blog
- debate's over: Globe is warming, USA Today
- There's no question that the Earth is getting hotter—and fast. The real questions are: How much of the warming is our fault, and are we willing to slow the meltdown by curbing our insatiable appetite for fossil fuels?, National Geographic
- How are humans responsible for global warming?, Environmental Defense Fund
- Water vapour is not the dominant greenhouse gas, Stoat
- Limiting Global Warming to 2°C: Can Europe and the United States Keep the Climate Window Open?, German Marshall Fund
- The climate challenge: Achieving zero emissions, OECD
- Rapid rise in methane emissions in 10 years surprises scientists The Guardian
- The 97% consensus on global warming
- For a thorough run-down, see the treatment of the scientific consensus on Wikipedia.
- Pentagon to rank global warming as a destabilizing force, Center for a New American Security
- The Pentagon Wants to Tackle Climate Change — But Congress Forbids It, io9
- Environmental Impacts of Hydroelectric Power: "run-of-the-river" and plants built in semi-arid regions are ok, but plants built in "tropical areas or temperate peatlands" do more harm than good.
- IPCC Working Group III – Mitigation of Climate Change, Annex III: Technology - specific cost and performance parameters IPCC. 2014. p. 10.
- Climate-Friendly Coal Technology Works But Is Proving Difficult To Scale Up
- Petra Nova, World’s Largest Post-Combustion Carbon-Capture Project, Begins Commercial Operation
- Making carbon capture and storage more attractive News item from the International Energy Agency (March 30, 2017)
- Scrubbing Carbon Dioxide From Air May Prove Too Costly, Scientific American
- Illinois scientists suggest cropping strategies to help farmers mitigate risks related to the impact of climate change on planting windows.
- The global tree restoration potential by Jean-Francois Bastin et al. (2019) Science 365(6448):76-79. doi:10.1126/science.aax0848.
- Climate change: Trees 'most effective solution' for warming by Matt McGrath (July 4, 2019).
- Space Colonization, NASA HQ Library
- Tea Party Co-Founder: Want to Win Over the GOP on Renewable Energy? Never Mention “Climate Change”
- Monbiot, George. Heat: How to to Stop the Planet from Burning, P. 40.
- As seen on Conservapedia.
- "The Global Warming Myth?", John Stossel
- IPCC model global warming projections have done much better than you think, Skeptical Science
- New argument from climate change deniers: global warming is a good thing, The Guardian
- See our article on Bjorn Lomborg.
- Christian Right Leader: Forget Carbon. Climate Change Is Caused By Sin!
- Watch a Supercut of Republicans Using China as an Excuse to Do Nothing About Climate Change, Mother Jones
- It's perhaps not relevant here, but this list of
idiociesreasons made me think about Sir Humphrey Appleby right away.
- See here for a full list of contradictory claims.
- Willerslev, Eske et al. Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland, Science. 6 July 2007: Vol. 317. no. 5834, pp. 111-4.
- Greenland ice yields hope on climate, The Boston Globe
- Greenland's ancient forests shed light on stability of ice sheet, Natural Environment Research Council
- A Global Balancing Act, Scent of Pine
- Climate myths: Human CO2 emissions are too tiny to matter, New Scientist
- Eos, Volcanic Versus Anthropogenic Carbon Dioxide, American Geophysical Union
- Global Carbon Budget
- Global CO2 Emissions from Fossil-Fuel Burning, Cement Manufacture, and Gas Flaring: 1751-2013
- Gerlach, T., (2011), Volcanic versus anthropogenic carbon dioxide, Eos Trans. AGU, 92( 24), 201.
- Which emits more carbon dioxide: volcanoes or human activities? by Michon Scott and Rebecca Lindsey (June 15, 2016)
- How do human CO2 emissions compare to natural CO2 emissions? by GPWayne, Skeptical Science
- Anti-Environmental Activist Denies Rising CO2 Levels, Insists 'Trees Give Off Carbon Dioxide' Right Wing Watch
- CO2 lags temperature — what does it mean?, Skeptical Science
- Ask A Climate Scientist — Lagging CO2
- WHAT ABOUT LAG TIME?, ClimateChangeConnection.org
- Climate myths: Ice cores show CO2 increases lag behind temperature rises, disproving the link to global warming by Michael Le Page and Catherine Brahic (16th May 2007) NewScientist
- Shakun, J., Clark, P., He, F. et al. Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation. Nature 484, 49–54 (2012). DOI:10.1038/nature10915 (See full article)
- Shakun et al. Clarify the CO2-Temperature Lag by dana1981 (10 April 2012) Skeptical Science
- What does the lag of CO2 behind temperature in ice cores tell us about global warming?, RealClimate
- The lag between temperature and CO2. (Gore’s got it right.), RealClimate
- Stips, A., Macias, D., Coughlan, C. et al. On the causal structure between CO2 and global temperature. Sci Rep 6, 21691 (2016). DOI:10.1038/srep21691 (Another scientific paper that reports the same conclusions)
- American Chemical Society It’s Water Vapor, Not the CO2
- Explaining how the water vapor greenhouse effect works, Skeptical Science
- Species multiply as Earth heats up: Biodiversity increases with gentle warming, Nature
- Correlation of global temperature with solar activity "While it appears that the measured solar cycle length tracks the temperature better than the CO2 concentration for the twentieth century up to 1970, this presented data remains quite controversial. When you look at the climate models that seek to show the human influence past 1970, you do see a good correlation of the temperature with the projected CO2 influence included, while the correlation with solar cycle length weakens."
- See the Wikipedia article on Orbit of Mars.
- Fenton, L., Geissler, P. & Haberle, R. Global warming and climate forcing by recent albedo changes on Mars. Nature 446, 646–649 (2007). https://doi.org/10.1038/nature05718
- "There IS a problem with global warming... it stopped in 1998"
- NASA Research Finds 2010 Tied for Warmest Year on Record, NASA
- What has global warming done since 1998?, Skeptical Science
- Cook at al. 2016. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming, Environ. Res. Lett. 11 048002
- Selected statements from the IPCC Fourth Assessment Report, Potsdam Institute for Climate Impact Research
- Oreskes, Naomi. The Scientific Consensus on Climate Change, Science. 3 December 2004: Vol. 306. no. 5702 p. 1686.
- What does Naomi Oreskes' study on consensus show?, Skeptical Science
- National Review column
- Influence of persistent wind scour on the surface mass balance of Antarctica
- Index of southern hemisphere sea ice
- From NOVA, "Are vapor trails from air traffic influencing the climate?"
- Lobbyist Dick Armey’s Pollution Gospel: ‘As An Article Of Faith,’ It Is ‘Pretentious’ To Believe In Global Warming, ThinkProgress
-  or  (You can also try Nature or Science.)
- Global-Warming Payola? The New York Times
- The Disinformation Cycle, Deltoid
- The Carbon Dioxide Greenhouse Effect, from The Discovery of Global Warming by Spencer Weart, American Institute of Physics
- Wingnut Dictionary — CAGW
- The consequences of climate change (in our lifetimes)
- Word Spy, on the term "warmist."
- An example: The Warmist Cult, American Stinker (Also note the article's brilliant use of Climategate, the Soros-Hansen canard, and the Maurice Strong conspiracy theory)
- Between Science and a Hard Place: The Intellectual Incoherence of Lukewarmism Part I, Part II, The Idiot Tracker
- The harmful impacts of climate change outweigh any benefits by sophia_whitaker (18th November 2020) Skeptical Science
- Her website
- Archive copy at the Wayback Machine
- Denise Chow, Three islands disappeared in the past year. Is climate change to blame?, NBC News 9 Jun. 2019
- "Sea level rise". 4 July 2012.
- "UK met Office Climate change" at the Wayback Machine
- Climate Change and Environmental Risk Atlas, Maplecroft
- Archive copy at the Wayback Machine
- Andrew K. Githeko et al. Climate change and vector-borne diseases: a regional analysis. Bulletin of the World Health Organization, 2000, 78 (9)
- Zoe Corbyn. Global Warming Wilts Malaria. Nature News, Dec. 21 2011.
- Carter T. Atkinson MS, PhD and Dennis A. LaPointe MS, PhD (2009). "Introduced Avian Diseases, Climate Change, and the Future of HawaiianHoneycreepers". Journal of Avian Medicine and Surgery, 23(1):53-63. 2009. http://dx.doi.org/10.1647/2008-059.1.
- One Gigantic Wild Card In Global Warming, ABC
- Glaciers melting faster
- Water shortage from Global Warming
- Background to the dispute over Hans Island
- Free Hans Island Parody Site
- Radio Free Hans Island Parody Site
- 21st Century US 'dustbowl' risk assessed
- Climate Change & Agriculture
- Climate change makes waking up to smell the coffee more expensive, NASA
- Tea industry's future depends on corporate collaboration, BBC
- Climate Change Could Melt Chocolate Production, Scientific American
- Bernanke's blog
- Future Climate Change Field Test Doesn't Make Earth Greener by Seth Borenstein (September, 6, 2016) Sci-Tech Today.
- Changing climate could worsen foods’ nutrition: Evidence builds for lessening of certain micronutrients, protein in plants by Susan Milius (3:07pm, March 13, 2017) Science News.
- A cost-benefit analysis of slowing climate change by David Maddison (Volume 23, Issues 4–5, April–May 1995, Pages 337-346) Elsevier.
- Global Warming: Pascal's Wager, Henry Thornton
- The Global Warming Wager, Bloomberg Businessweek
- Plot idea: 97% of the world's scientists contrive an environmental crisis, but are exposed by a plucky band of billionaires & oil companies. by Scott Westerfeld (5:27 PM - 20 Mar 2014) Twitter (archived from 17 Nov 2020 08:41:23 UTC).
- Timeline - Discovery of Global Warming
- Towards a genealogy of climate conspiracy theories, International Journal of Inactivism
- Didn't the UN already collectively take over the world, or most of it already? I mean the member nations spans almost the entire world's land above water. I can understand taking over a country as in interfering the policies of that country, but the world as a whole is mostly controlled by UN as a whole since pretty much after World War II.
- Maybe it is because it is the people who came up with this conspiracy theory who deny funding to the scientists.
- Melanie Phillips!
- Naomi Oreskes and Erik M. Conway. Challenging Knowledge: How Climate Science Became a Victim of the Cold War. In Agnotology: The Cultural Production of Ignorance, edited by Robert Proctor and Londa Schiebinger, Stanford University Press.
- Outside Crazy Red-baiter World, "memetic weapons" are better known as "advertising". Um...
- The Link Between Eugenics and Global Warming Hype, New American
- If humans are a virus, then what is the end game? Info Wars
- Margaret Mead's Bashers Owe Her an Apology, John Horgan
- The Energy 202: Why climate change deniers mistrust hurricane forecasts too by Dino Grandoni (September 7, 2017 at 8:50 AM) The Washington Post.
- Rush Limbaugh indicates he’s evacuating Palm Beach days after suggesting Hurricane Irma is fake news by Callum Borchers (September 8, 2017 at 10:45 AM) The Washington Post.
- The Climate Deception Dossiers (July 9, 2015 update) Union of Concerned Scientists
- Deception Dossiers: All Documents Union of Concerned Scientists
- 1981 Exxon Coal TV Commercial by ewjxn (Jun 16, 2016) YouTube. "This is a commercial I clipped from a 1981 episode of Barney Miller my father recorded on Betamax. It originally aired on KTVK Channel 3 in the Phoenix market. The commercial features Exxon's Coal division!"
- Global Warming Skeptics: A Primer, Environmental Defense Fund
- The Guardian: Secretive donors gave US climate denial groups $125m over three years
- http://scienceblogs.com/denialism/2007/10/17/al-gore-and-the-attack-of-the/ Al Gore and the Attack of the Global Warming Cranks], ScienceBlogs
- ExxonMobil’s Continued Funding of Global Warming Denial Industry, Greenpeace
- Smoke Signals, Grist
- Among the granddaddies that kept popping up were S. Fred Singer and the late Frederick Seitz. See Naomi Oreskes and Erik M. Conway. Merchants of Doubt. Bloomsbury Press, 2011. ISBN 1-608-19394-2
- CDIAC list of greenhouse gases
- IPCC list of greenhouse gases
- Impacts of water, carbon dioxide, methane and ozone on the overall greenhouse effect, See also  for a summary
- AccuWeather misleads on global warming and heat waves, a throwback to its past climate denial by Jason Samenow & Andrew Freedman (August 9, 2019) The Washington Post.
- UK Secretary of State for the Environment reveals his depth of knowledge of climate change, Skeptical Science
- Scott Pruitt, longtime adversary of EPA, confirmed to lead the agency by Brady Dennis (February 17 at 1:50 PM) The Washington Post.
- This very expensive GLOBAL WARMING bullshit has got to stop. Our planet is freezing, record low temps,and our GW scientists are stuck in ice by Donald J. Trump (16:39 - January 1, 2014) Twitter (archived from February 23, 2014).