More proof of Global Warming

Statements by concurring organizations

Intergovernmental Panel on Climate Change (IPCC) 2007

Main article: Intergovernmental Panel on Climate Change

In February 2007, the IPCC released a summary of the forthcoming Fourth Assessment Report. According to this summary, the Fourth Assessment Report finds that human actions are "very likely" the cause of global warming, meaning a 90% or greater probability. Global warming in this case is indicated by an increase of 0.75 degrees in average global temperatures over the last 100 years.[2]

The New York Times reports on the report:

The world's leading climate scientists said global warming has begun, is very likely caused by man, and will be unstoppable for centuries, ... . The phrase very likely translates to a more than 90 percent certainty that global warming is caused by man's burning of fossil fuels. That was the strongest conclusion to date, making it nearly impossible to say natural forces are to blame.[3]

The report said that an increase in hurricane and tropical cyclone strength since 1970 more likely than not can be attributed to man-made global warming. The scientists said global warming's connection varies with storms in different parts of the world, but that the storms that strike the Americas are global warming-influenced.[4]

The Associated Press summarizes the position on sea level rise:

On sea levels, the report projects rises of 7-23 inches by the end of the century. That could be augmented by an additional 4-8 inches if recent surprising polar ice sheet melt continues.[5]

InterAcademy Council

As the representative of the world’s scientific and engineering academies,[6][7] the InterAcademy Council (IAC) issued a report in 2007 entitled Lighting the Way: Toward a Sustainable Energy Future.

Current patterns of energy resources and energy usage are proving detrimental to the long-term welfare of humanity. The integrity of essential natural systems is already at risk from climate change caused by the atmospheric emissions of greenhouse gases.[8]

Concerted efforts should be mounted for improving energy efficiency and reducing the carbon intensity of the world economy.[9]

Joint science academies' statement 2008

In preparation for the 34th G8 summit, the national science academies of the G8+5 nations issued a declaration reiterating the position of the 2005 joint science academies’ statement, and reaffirming “that climate change is happening and that anthropogenic warming is influencing many physical and biological systems.” Among other actions, the declaration urges all nations to “(t)ake appropriate economic and policy measures to accelerate transition to a low carbon society and to encourage and effect changes in individual and national behaviour.”[10]

The thirteen signatories were the national science academies of Brazil, Canada, China, France, Germany, Italy, India, Japan, Mexico, Russia, South Africa, the United Kingdom, and the United States.

Joint science academies’ statement 2007

In preparation for the 2007 G8 summit, the national science academies of the G8+5 nations issued a declaration referencing the position of the 2005 joint science academies' statement, and acknowledging the confirmation of their previous conclusion by recent research. Following the IPCC Fourth Assessment Report, the declaration states:

It is unequivocal that the climate is changing, and it is very likely that this is predominantly caused by the increasing human interference with the atmosphere. These changes will transform the environmental conditions on Earth unless counter-measures are taken.

The thirteen signatories were the national science academies of Brazil, Canada, China, France, Germany, Italy, India, Japan, Mexico, Russia, South Africa, the United Kingdom, and the United States.

Joint science academies’ statement 2005

In 2005 the national science academies of the G8 nations, plus Brazil, China and India, three of the largest emitters of greenhouse gases in the developing world, signed a statement on the global response to climate change. The statement stresses that the scientific understanding of climate change is now sufficiently clear to justify nations taking prompt action[11], and explicitly endorsed the IPCC consensus. The eleven signatories were the science academies of Brazil, Canada, China, France, Germany, India, Italy, Japan, Russia, the United Kingdom, and the United States.

Joint science academies’ statement 2001

In 2001, following the publication of the IPCC Third Assessment Report, sixteen national science academies issued a joint statement explicitly acknowledging the IPCC position as representing the scientific consensus on climate change science. The sixteen science academies that issued the statement were those of Australia, Belgium, Brazil, Canada, the Caribbean, China, France, Germany, India, Indonesia, Ireland, Italy, Malaysia, New Zealand, Sweden, and the United Kingdom.[12]

International Council of Academies of Engineering and Technological Sciences

In October 2007, the International Council of Academies of Engineering and Technological Sciences (CAETS) issued a Statement on Environment and Sustainable Growth[13]

As reported by the Intergovernmental Panel on Climate Change (IPCC), most of the observed global warming since the mid-20th century is very likely due to human-produced emission of greenhouse gases and this warming will continue unabated if present anthropogenic emissions continue or, worse, expand without control.

CAETS, therefore, endorses the many recent calls to decrease and control greenhouse gas emissions to an acceptable level as quickly as possible.

European Academy of Sciences and Arts

In March 2007, the European Academy of Sciences and Arts issued a formal declaration in which they stated, “Human activity is most likely responsible for climate warming. Most of the climatic warming over the last 50 years is likely to have been caused by increased concentrations of greenhouse gases in the atmosphere. 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. The above development potentially has dramatic consequences for mankind’s future. “[14]

Network of African Science Academies

In 2007, the Network of African Science Academies submitted a joint “statement on sustainability, energy efficiency, and climate change” to the leaders meeting at the G8 Summit in Heiligendamm, Germany.

“A consensus, based on current evidence, now exists within the global scientific community that human activities are the main source of climate change and that the burning of fossil fuels is largely responsible for driving this change.”

“The IPCC should be congratulated for the contribution it has made to public understanding of the nexus that exists between energy, climate and sustainability.”[15]

The thirteen signatories were the science academies of Cameroon, Ghana, Kenya, Madagascar, Nigeria, Senegal, South Africa, Sudan, Tanzania, Uganda, Zambia, Zimbabwe, as well as the African Academy of Sciences.

Royal Society of New Zealand

On July 10, 2008, the Royal Society of New Zealand released a statement, which said in summary:

The globe is warming because of increasing greenhouse gas emissions. Measurements show that greenhouse gas concentrations in the atmosphere are well above levels seen for many thousands of years. Further global climate changes are predicted, with impacts expected to become more costly as time progresses. Reducing future impacts of climate change will require substantial reductions of greenhouse gas emissions.[16]

National Research Council (US)

In 2001, the Committee on the Science of Climate Change of the National Research Council published Climate Change Science: An Analysis of Some Key Questions.[17] This report explicitly endorses the IPCC view of attribution of recent climate change as representing the view of the scientific community:

The changes observed over the last several decades are likely mostly due to human activities, but we cannot rule out that some significant part of these changes is also a reflection of natural variability. Human-induced warming and associated sea level rises are expected to continue through the 21st century... The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue.[17]

European Science Foundation

In 2007, the European Science Foundation issued a Position Paper on climate change in which they concur, "There is now convincing evidence that since the industrial revolution, human activities, resulting in increasing concentrations of greenhouse gases have become a major agent of climate change. These greenhouse gases affect the global climate by retaining heat in the troposphere, thus raising the average temperature of the planet and altering global atmospheric circulation and precipitation patterns." The paper concluded, "While on-going national and international actions to curtail and reduce greenhouse gas emissions are essential, the levels of greenhouse gases currently in the atmosphere, and their impact, are likely to persist for several decades. On-going and increased efforts to mitigate climate change through reduction in greenhouse gases are therefore crucial."[18]

American Association for the Advancement of Science

In December 2006, the American Association for the Advancement of Science adopted an official statement on climate change in which they stated, "The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society....The pace of change and the evidence of harm have increased markedly over the last five years. The time to control greenhouse gas emissions is now."[19]

Federation of American Scientists

In their Energy and Environment Overview, the Federation of American Scientists state, “There is no serious doubt that human activity is altering the earth's climate in potentially catastrophic ways. Even skeptics are forced to admit that the risk is real and that prudence demands action if only as an insurance policy, the only serious debate is about how best to respond." [20]

World Meteorological Organization

In its Statement at the Twelfth Session of the Conference of the Parties to the U.N. Framework Convention on Climate Change, the World Meteorological Organization (WMO) confirms the need to “prevent dangerous anthropogenic interference with the climate system.” The WMO concurs that “scientific assessments have increasingly reaffirmed that human activities are indeed changing the composition of the atmosphere, in particular through the burning of fossil fuels for energy production and transportation.” The WMO concurs that “the present atmospheric concentration of CO2 was never exceeded over the past 420,000 years;” and that the IPCC “assessments provide the most authoritative, up-to-date scientific advice.” [21]

American Meteorological Society

The American Meteorological Society (AMS) statement adopted by their council in 2003 said:

There is now clear evidence that the mean annual temperature at the Earth's surface, averaged over the entire globe, has been increasing in the past 200 years. There is also clear evidence that the abundance of greenhouse gases in the atmosphere has increased over the same period. In the past decade, significant progress has been made toward a better understanding of the climate system and toward improved projections of long-term climate change... Human activities have become a major source of environmental change. Of great urgency are the climate consequences of the increasing atmospheric abundance of greenhouse gases... Because greenhouse gases continue to increase, we are, in effect, conducting a global climate experiment, neither planned nor controlled, the results of which may present unprecedented challenges to our wisdom and foresight as well as have significant impacts on our natural and societal systems.[22]

Royal Meteorological Society (UK)

In February 2007, after the release of the IPCC’s Fourth Assessment Report, the Royal Meteorological Society issued an endorsement of the report. In addition to referring to the IPCC as “world’s best climate scientists”, they stated that climate change is happening as “the result of emissions since industrialization and we have already set in motion the next 50 years of global warming – what we do from now on will determine how worse it will get.” [23]

Australian Meteorological and Oceanographic Society

The Australian Meteorological and Oceanographic Society has issued a Statement on Climate Change, wherein they conclude, “Global climate change and global warming are real and observable…It is highly likely that those human activities that have increased the concentration of greenhouse gases in the atmosphere have been largely responsible for the observed warming since 1950. The warming associated with increases in greenhouse gases originating from human activity is called the enhanced greenhouse effect. The atmospheric concentration of carbon dioxide has increased by more than 30% since the start of the industrial age and is higher now than at any time in at least the past 650,000 years. This increase is a direct result of burning fossil fuels, broad-scale deforestation and other human activity.”[24]

Canadian Meteorological and Oceanographic Society

"CMOS endorses the process of periodic climate science assessment carried out by the Intergovernmental Panel on Climate Change and supports the conclusion, in its Third Assessment Report, which states that the balance of evidence suggests a discernible human influence on global climate."[25]

Canadian Foundation for Climate and Atmospheric Sciences

In November 2005, the Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) issued a letter to the Prime Minister of Canada stating that "We concur with the climate science assessment of the Intergovernmental Panel on Climate Change (IPCC) in 2001 ... We endorse the conclusions of the IPCC assessment that 'There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities'. ... There is increasingly unambiguous evidence of changing climate in Canada and around the world. There will be increasing impacts of climate change on Canada’s natural ecosystems and on our socio-economic activities. Advances in climate science since the 2001 IPCC Assessment have provided more evidence supporting the need for action and development of a strategy for adaptation to projected changes."[26]

International Union for Quaternary Research

The statement on climate change issued by the International Union for Quaternary Research reiterates the conclusions of the IPCC, and urges all nations to take prompt action in line with the UNFCCC principles.

“Human activities are now causing atmospheric concentrations of greenhouse gasses - including carbon dioxide, methane, tropospheric ozone, and nitrous oxide - to rise well above pre-industrial levels….Increases in greenhouse gasses are causing temperatures to rise…The scientific understanding of climate change is now sufficiently clear to justify nations taking prompt action….Minimizing the amount of this carbon dioxide reaching the atmosphere presents a huge challenge but must be a global priority.” [27]

American Quaternary Association

The American Quaternary Association (AMQUA) has stated, “Few credible Scientists now doubt that humans have influenced the documented rise of global temperatures since the Industrial Revolution,” citing “the growing body of evidence that warming of the atmosphere, especially over the past 50 years, is directly impacted by human activity.” [28]

Stratigraphy Commission of the Geological Society of London

In its position paper on global warming, the Stratigraphy Commission of the Geological Society of London declares, "Global climate change is increasingly recognised as the key threat to the continued development – and even survival - of humanity." They refer to the IPCC as providing the "most authoritative assessment of climate change", and further state, "We find that the evidence for human-induced climate change is now persuasive, and the need for direct action compelling."[29]

International Union of Geodesy and Geophysics

In July 2007, the International Union of Geodesy and Geophysics (IUGG) adopted a resolution entitled “The Urgency of Addressing Climate Change”. In it, the IUGG concurs with the “comprehensive and widely accepted and endorsed scientific assessments carried out by the International Panel on Climate Change and regional and national bodies, which have firmly established, on the basis of scientific evidence, that human activities are the primary cause of recent climate change.” They state further that the “continuing reliance on combustion of fossil fuels as the world’s primary source of energy will lead to much higher atmospheric concentrations of greenhouse gasses, which will, in turn, cause significant increases in surface temperature, sea level, ocean acidification, and their related consequences to the environment and society.” [30]

International Union of Geological Sciences

In their Climate Change prospectus for the International Year of Planet Earth project, the International Union of Geological Sciences (IUGS) stated, “The idea that there is a strong human imprint on recent climate change is now compelling, with forest clearing, building and man-made gas emissions all having a strong influence on Earth’s warming.”[31]

We know that human activity has resulted in changes to atmospheric chemistry and land cover, and caused serious decline in biodiversity.[32]

European Geosciences Union

In 2005, the Divisions of Atmospheric and Climate Sciences of the European Geosciences Union (EGU) issued a position statement in support of the joint science academies’ statement on global response to climate change. The statement refers to the Intergovernmental Panel on Climate Change (IPCC), as "the main representative of the global scientific community", and asserts that the IPCC “represents the state-of-the-art of climate science supported by the major science academies around the world and by the vast majority of science researchers and investigators as documented by the peer-reviewed scientific literature.”[33]

Additionally, in 2008, the EGU issued a position statement on ocean acidification which states, "Ocean acidification is already occurring today and will continue to intensify, closely tracking atmospheric CO2 increase. Given the potential threat to marine ecosystems and its ensuing impact on human society and economy, especially as it acts in conjunction with anthropogenic global warming, there is an urgent need for immediate action." The statement then advocates for strategies "to limit future release of CO2 to the atmosphere and/or enhance removal of excess CO2 from the atmosphere."[34]

Canadian Federation of Earth Sciences

The Canadian Federation Of Earth Sciences has issued a position paper on global climate change in which they state, “ Canada's Earth scientists also recognize that humans are adding greenhouse gases (GHGs) to our atmosphere at an ever increasing rate. The level of CO2 in our atmosphere is now greater than at any time in the past 500,000 years; there will be consequences for our global climate and natural systems as a result….These could include: increased frequency and severity of drought, coastal erosion, sea level change, permafrost degradation, impact of reduced glacier cover on water resources, groundwater quality and quantity, and occurrence of climate-related natural hazards such as flooding, dust storms and landslides.”[35]

Geological Society of America

"The Geological Society of America (GSA) supports the scientific conclusions that Earth’s climate is changing; the climate changes are due in part to human activities; and the probable consequences of the climate changes will be significant and blind to geopolitical boundaries. Furthermore, the potential implications of global climate change and the time scale over which such changes will likely occur require active, effective, long-term planning."[36]

American Geophysical Union

The American Geophysical Union (AGU) statement [37] adopted by the society in 2003 and revised in 2007 affirms that rising levels of greenhouse gases have caused and will continue to cause the global surface temperature to be warmer:

The Earth's climate is now clearly out of balance and is warming. Many components of the climate system—including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons—are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century. Global average surface temperatures increased on average by about 0.6°C over the period 1956–2006. As of 2006, eleven of the previous twelve years were warmer than any others since 1850. The observed rapid retreat of Arctic sea ice is expected to continue and lead to the disappearance of summertime ice within this century. Evidence from most oceans and all continents except Antarctica shows warming attributable to human activities. Recent changes in many physical and biological systems are linked with this regional climate change. A sustained research effort, involving many AGU members and summarized in the 2007 assessments of the Intergovernmental Panel on Climate Change, continues to improve our scientific understanding of the climate.

American Astronomical Society

The American Astronomical Society has endorsed the AGU statement:[38]

In endorsing the "Human Impacts on Climate" statement [issued by the American Geophysical Union], the AAS recognizes the collective expertise of the AGU in scientific subfields central to assessing and understanding global change, and acknowledges the strength of agreement among our AGU colleagues that the global climate is changing and human activities are contributing to that change.

American Institute of Physics

The Governing Board of the American Institute of Physics endorsed the AGU statement on human-induced climate change:[39]

The Governing Board of the American Institute of Physics has endorsed a position statement on climate change adopted by the American Geophysical Union (AGU) Council in December 2003.

American Physical Society

In November 2007, the American Physical Society (APS) adopted an official statement on climate change: "Emissions of greenhouse gases from human activities are changing the atmosphere in ways that affect the Earth's climate. Greenhouse gases include carbon dioxide as well as methane, nitrous oxide and other gases. They are emitted from fossil fuel combustion and a range of industrial and agricultural processes.

"The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now."[40]

American Chemical Society

The American Chemical Society stated:

Careful and comprehensive scientific assessments have clearly demonstrated that the Earth’s climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007). There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change.

The reality of global warming, its current serious and potentially disastrous impacts on Earth system properties, and the key role emissions from human activities play in driving these phenomena have been recognized by earlier versions of this ACS policy statement (ACS, 2004), by other major scientific societies, including the American Geophysical Union (AGU, 2003), the American Meteorological Society (AMS, 2007) and the American Association for the Advancement of Science (AAAS, 2007), and by the U. S. National Academies and ten other leading national academies of science (NA, 2005).[41]

American Society for Microbiology

In 2003, the American Society for Microbiology issued a public policy report in which they recommend “reducing net anthropogenic CO2 emissions to the atmosphere” and “minimizing anthropogenic disturbances of” atmospheric gasses:[42]

Carbon dioxide concentrations were relatively stable for the past 10,000 years but then began to increase rapidly about 150 years ago…as a result of fossil fuel consumption and land use change.[43]

Of course, changes in atmospheric composition are but one component of global change, which also includes disturbances in the physical and chemical conditions of the oceans and land surface. Although global change has been a natural process throughout Earth’s history, humans are responsible for substantially accelerating present-day changes. These changes may adversely affect human health and the biosphere on which we depend.[44]

Outbreaks of a number of diseases, including Lyme disease, hantavirus infections, dengue fever, bubonic plague, and cholera, have been linked to climate change.[45]

Institute of Biology (UK)

The UK's Institute of Biology states “there is scientific agreement that the rapid global warming that has occurred in recent years is mostly anthropogenic, ie due to human activity.” As a consequence of global warming, they warn that a “rise in sea levels due to melting of ice caps is expected to occur. Rises in temperature will have complex and frequently localised effects on weather, but an overall increase in extreme weather conditions and changes in precipitation patterns are probable, resulting in flooding and drought. The spread of tropical diseases is also expected.” Subsequently, the Institute of Biology advocates policies to reduce “greenhouse gas emissions, as we feel that the consequences of climate change are likely to be severe.”[46]

World Federation of Public Health Associations

In 2001, the World Federation of Public Health Associations issued a policy resolution on global climate change:

Noting the conclusions of the United Nations' Intergovernmental Panel on Climate Change (IPCC) and other climatologists that anthropogenic greenhouse gases, which contribute to global climate change, have substantially increased in atmospheric concentration beyond natural processes and have increased by 28 percent since the industrial revolution….Realizing that subsequent health effects from such perturbations in the climate system would likely include an increase in: heat-related mortality and morbidity; vector-borne infectious diseases,… water-borne diseases…(and) malnutrition from threatened agriculture….the World Federation of Public Health Associations…recommends precautionary primary preventive measures to avert climate change, including reduction of greenhouse gas emissions and preservation of greenhouse gas sinks through appropriate energy and land use policies, in view of the scale of potential health impacts....[47]

American Public Health Association

In 2007, the American Public Health Association issued a policy statement entitled ‘’Addressing the Urgent Threat of Global Climate Change to Public Health and the Environment’’:

The long-term threat of global climate change to global health is extremely serious and the fourth IPCC report and other scientific literature demonstrate convincingly that anthropogenic GHG emissions are primarily responsible for this threat….US policy makers should immediately take necessary steps to reduce US emissions of GHGs, including carbon dioxide, to avert dangerous climate change.[48]

American Medical Association

In 2008, the American Medical Association issued a policy statement on global climate change declaring that they:

Support the findings of the latest Intergovernmental Panel on Climate Change report, which states that the Earth is undergoing adverse global climate change and that these changes will negatively effect public health.

Support educating the medical community on the potential adverse public health effects of global climate change, including topics such as population displacement, flooding, infectious and vector-borne diseases, and healthy water supplies.[49]

American College of Preventive Medicine

In 2006, the American College of Preventive Medicine issued a policy statement on “Abrupt Climate Change and Public Health Implications”:

The American College of Preventive Medicine (ACPM) accept the position that global warming and climate change is occurring, that there is potential for abrupt climate change, and that human practices that increase greenhouse gases exacerbate the problem, and that the public health consequences may be severe.[50]

American Association of Wildlife Veterinarians

The American Association of Wildlife Veterinarians (AAWV) has issued a position statement regarding "climate change, wildlife diseases, and wildlife health":

There is widespread scientific agreement that the world’s climate is changing and that the weight of evidence demonstrates that anthropogenic factors have and will continue to contribute significantly to global warming and climate change. It is anticipated that continuing changes to the climate will have serious negative impacts on public, animal and ecosystem health due to extreme weather events, changing disease transmission dynamics, emerging and re-emerging diseases, and alterations to habitat and ecological systems that are essential to wildlife conservation. Furthermore, there is increasing recognition of the inter-relationships of human, domestic animal, wildlife, and ecosystem health as illustrated by the fact the majority of recent emerging diseases have a wildlife origin.[51]

Wildlife Society

The Wildlife Society has issued a position statement entitled Global Climate Change and Wildlife:[52]

Scientists throughout the world have concluded that climate research conducted in the past two decades definitively shows that rapid worldwide climate change occurred in the 20th century, and will likely continue to occur for decades to come. Although climates have varied dramatically since the earth was formed, few scientists question the role of humans in exacerbating recent climate change through the emission of greenhouse gases. The critical issue is no longer “if” climate change is occurring, but rather how to address its effects on wildlife and wildlife habitats.

The statement goes on to assert that “evidence is accumulating that wildlife and wildlife habitats have been and will continue to be significantly affected by ongoing large-scale rapid climate change.”

The statement concludes with an call for “reduction in anthropogenic (human-caused) sources of carbon dioxide and other greenhouse gas emissions contributing to global climate change and the conservation of CO2- consuming photosynthesizers (i.e., plants).”

Australian Coral Reef Society

In 2006, the Australian Coral Reef Society issued an official communique regarding the Great Barrier Reef and the "world-wide decline in coral reefs through processes such as overfishing, runoff of nutrients from the land, coral bleaching, global climate change, ocean acidification, pollution", etc.:

There is almost total consensus among experts that the earth’s climate is changing as a result of the build-up of greenhouse gases. The IPCC (involving over 3 thousand of the world’s experts) has come out with clear conclusions as to the reality of this phenomenon. One does not have to look further than the collective academy of scientists worldwide to see the string (of) statements on this worrying change to the earth’s atmosphere.

There is broad scientific consensus that coral reefs are heavily affected by the activities of man and there are significant global influences that can make reefs more vulnerable such as global warming....It is highly likely that coral bleaching has been exacerbated by global warming[53]

Water Environment Federation

In 2006, the Water Environment Federation issued a resolution on climate change stating “there is scientific consensus, as established by the Intergovernmental Panel on Climate Change and confirmed by the National Academy of Sciences, that the build-up of greenhouse gases from human sources, including carbon dioxide and methane, in the atmosphere is causing global temperatures to increase and threaten the stability of our planet’s climate…” They further warn “there will be significant disruptions in the natural hydrological cycle in various regions of the world, including extreme and more frequent wet weather events; increased flooding due to higher precipitation; severe and more frequent drought; increased water temperatures; and rising sea levels leading to saltwater intrusion in coastal aquifers…”[54]

Chartered Institution of Water and Environmental Management

In 2006, the Chartered Institution of Water and Environmental Management issued a policy position statement on global climate change wherein they confirm, “The scientific consensus is that human activity is changing the climate, as evidenced in the recent temperature record…”, and advocate for the “strengthening of international agreements on climate change, including the Kyoto Protocol, to ensure greenhouse gas emissions are capped and reduced in a meaningful and timely manner…”[55]

American Statistical Association

On November 30, 2007, the American Statistical Association Board of Directors adopted a statement on climate change:

The ASA endorses the IPCC conclusions. ... Over the course of four assessment reports, a small number of statisticians have served as authors or reviewers. Although this involvement is encouraging, it does not represent the full range of statistical expertise available. ASA recommends that more statisticians should become part of the IPCC process. Such participation would be mutually beneficial to the assessment of climate change and its impacts and also to the statistical community.[56]

Engineers Australia (The Institution of Engineers Australia)

"Engineers Australia believes that Australia must act swiftly and proactively in line with global expectations to address climate change as an economic, social and environmental risk... We believe that addressing the costs of atmospheric emissions will lead to increasing our competitive advantage by minimising risks and creating new economic opportunities. Engineers Australia believes the Australian Government should ratify the Kyoto Protocol."[57]

Federal Climate Change Science Program (US)

On May 2, 2006, the Federal Climate Change Science Program, commissioned by the Bush administration in 2002, released the first of 21 assessments. Though it did not state what percentage of climate change might be anthropogenic, the assessment concluded:

Studies ... show clear evidence of human influences on the climate system (due to changes in greenhouse gases, aerosols, and stratospheric ozone). ... The observed patterns of change over the past 50 years cannot be explained by natural processes alone, nor by the effects of short-lived atmospheric constituents (such as aerosols and tropospheric ozone) alone.[58]

In a May 29, 2008 assessment, they stated:

It is well established through formal attribution studies that the global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases.[59]

Noncommittal statements

American Association of State Climatologists

The 2001 statement from the American Association of State Climatologists noted the difficulties with predicting impacts due to climate change, while acknowledging that human activities are having an effect on climate:

Climate prediction is difficult because it involves complex, nonlinear interactions among all components of the earth’s environmental system. (...) The AASC recognizes that human activities have an influence on the climate system. Such activities, however, are not limited to greenhouse gas forcing and include changing land use and sulfate emissions, which further complicates the issue of climate prediction. Furthermore, climate predictions have not demonstrated skill in projecting future variability and changes in such important climate conditions as growing season, drought, flood-producing rainfall, heat waves, tropical cyclones and winter storms. These are the type of events that have a more significant impact on society than annual average global temperature trends. Policy responses to climate variability and change should be flexible and sensible – The difficulty of prediction and the impossibility of verification of predictions decades into the future are important factors that allow for competing views of the long-term climate future. Therefore, the AASC recommends that policies related to long-term climate not be based on particular predictions, but instead should focus on policy alternatives that make sense for a wide range of plausible climatic conditions regardless of future climate... Finally, ongoing political debate about global energy policy should not stand in the way of common sense action to reduce societal and environmental vulnerabilities to climate variability and change. Considerable potential exists to improve policies related to climate.[60]

American Association of Petroleum Geologists

The American Association of Petroleum Geologists (AAPG) Position Statement on climate change states that "the AAPG membership is divided on the degree of influence that anthropogenic CO2 has on recent and potential global temperature increases ... Certain climate simulation models predict that the warming trend will continue, as reported through NAS, AGU, AAAS and AMS. AAPG respects these scientific opinions but wants to add that the current climate warming projections could fall within well-documented natural variations in past climate and observed temperature data. These data do not necessarily support the maximum case scenarios forecast in some models."[61]

Prior to the adoption of this statement, the AAPG was the only major scientific organization that rejected the finding of significant human influence on recent climate, according to a statement by the Council of the American Quaternary Association.[62] Explaining the plan for a revision, AAPG president Lee Billingsly wrote in March 2007 that "Members have threatened to not renew their memberships ... if AAPG does not alter its position on global climate change ... . And I have been told of members who already have resigned in previous years because of our current global climate change position. ... The current policy statement is not supported by a significant number of our members and prospective members."[63]

Statements by dissenting organizations

With the July 2007 release of the revised statement by the American Association of Petroleum Geologists, no remaining scientific body of national or international standing is known to reject the basic findings of human influence on recent climate.[62]

No to 2012 wrote:

I agree - a load of Bollocks.

What is the earth’s optimum climate?

It continuously changes and has done for aeons, long before mankind appeared

We know the planet’s had successive ice-ages - and we also know it’s been warmer than it is today - and not so long ago either.

Eric the Red took his Norsemen to Greenland in the 10th century to farm in that temperate climate, it’s why he named it Greenland.

They farmed there for 3 centuries, longer than the United States has existed.

Today, the old Viking farmsteads are covered by glaciers.

I don’t think Eric and his chums were pumping much CO2 into the atmosphere from their 4 by 4s!

So we know the earth has been warmer within recent history - if the earth gets warm enough for humans to actually farm again in places like Greenland - how do we know, as with the Vikings, we won’t experience again, another ’little ice age’, similar to that, that made the Viking flee Greenland - the little ice age we’ve been coming out of ever since.

Ditto wrote:

Distribution is important. Maybe you only have 2 beers a week when averaged out over the whole year. No big deal. But you didn't evenly space them throughout the year. Instead, you drank them all on 4th of July weekend, fell down, and broke your leg. Have a great season!

Two degrees Farenheit doesn't sound like a lot to the average lummox (like the OP). Except when it's the two degrees that separates 31 degF from 33 degF. That means earlier snow melts and precipitation falling as rain instead of snow. Water distribution and temperature is a lot more important than air temperature for both the global system and our human fraction of it.

Even if the mean global temperature didn't change, any flattening of the current distribution would create serious problems. All our infrastructure and biological systems are based on a 10% event happening 10% of the time, not 12% of the time.

Global warming denialists on the internet can be broken down into:

20% "free-thinkers" who "feel" like they know more than the authorities on any issue, like the horrors of vaccines.

30% cretins who truly believe anything Glenn Beck or Mike Savage tells them because the librul meedya hates freedom and human civilization (especially white men)

50% trolls

Trolls, I don't have a problem with...