Nearly all publishing climate scientists (97–98%) are convinced by the evidence that humans are significantly contributing to global warming.
This is a list of scientists who have made statements that conflict with the scientific consensus on global warming as summarized by the Intergovernmental Panel on Climate Change and endorsed by other scientific bodies. A minority are climatologists. Nearly all publishing climate scientists (97–98%) support the consensus on anthropogenic climate change.
The scientific consensus is that the global average surface temperature has risen over the past century. Scientific opinion on climate change was summarized in the 2001 Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). The main conclusions on global warming at that time were as follows:
- The global average surface temperature has risen 0.6 ± 0.2 °C since the late 19th century, and 0.17 °C per decade in the years 1971–2001.
- "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities", in particular emissions of the greenhouse gases carbon dioxide and methane.
- If greenhouse gas emissions continue the warming will also continue, with temperatures projected to increase by 1.4 °C to 5.8 °C between 1990 and 2100. Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise. The balance of impacts of global warming become significantly negative at larger values of warming.
These findings are recognized by the national science academies of all the major industrialized nations; the consensus has strengthened over time and is now virtually unanimous. The level of consensus correlates with expertise in climate science.
There have been several efforts to compile lists of dissenting scientists, including a 2008 US senate minority report, the Oregon Petition, and a 2007 list by the Heartland Institute, all three of which have been criticized on a number of grounds.
For the purpose of this list, a "scientist" is defined as an
individual who has published at least one peer-reviewed research article
in the broad field of natural sciences, although not necessarily in a
field relevant to climatology. Since the publication of the IPCC Third
Assessment Report, each has made a clear statement in his or her own
words (as opposed to the name being found on a petition, etc.)
disagreeing with one or more of the report's three main conclusions, and
each has been described in reliable sources as a climate skeptic,
denier, or in disagreement with any of the three main conclusions. Their
views on climate change are usually described in more detail in their
biographical articles. Few of the statements in the references for this
list are part of the peer-reviewed scientific literature; most are from other sources such as interviews, opinion pieces, online essays and presentations.
Nota bene: Only individuals who have their own Wikipedia article may be included in the list.
Scientists questioning the accuracy of IPCC climate projections
These scientists have said that it is not possible to project global
climate accurately enough to justify the ranges projected for
temperature and sea-level rise over the 21st century. They may not
conclude specifically that the current IPCC projections are either too
high or too low, but that the projections are likely to be inaccurate
due to inadequacies of current global climate modeling.
- Craig Loehle, ecologist and chief scientist at the National Council for Air and Stream Improvement.
- Garth Paltridge, retired chief research scientist, CSIRO Division of Atmospheric Research and retired director of the Institute of the Antarctic Cooperative Research Centre, visiting fellow Australian National University.
- Susan Crockford, Zoologist, adjunct professor in Anthropology at the University of Victoria.
- Ross McKitrick, professor of economics and CBE chair in sustainable commerce, University of Guelph.
- Patrick Moore, former president of Greenpeace Canada.
- Denis Rancourt, former professor of physics at University of Ottawa, research scientist in condensed matter physics, and in environmental and soil science.
- Fritz Vahrenholt, German politician and energy executive with a doctorate in chemistry.
- Hendrik Tennekes, retired director of research, Royal Netherlands Meteorological Institute.
- Ivar Giaever, Norwegian–American physicist and Nobel laureate in physics (1973).
- Steven E. Koonin, theoretical physicist and director of the Center for Urban Science and Progress at New York University.
- Nils-Axel Mörner, retired head of the Paleogeophysics and Geodynamics Department at Stockholm University, former chairman of the INQUA Commission on Sea Level Changes and Coastal Evolution (1999–2003).
- Peter Stilbs, professor of physical chemistry at Royal Institute of Technology, Stockholm.
- David Bellamy, botanist.
- Lennart Bengtsson, meteorologist, Reading University.
- Piers Corbyn, owner of the business WeatherAction which makes weather forecasts.
- Michael J. Kelly, Prince Phillip Professor of Technology at the Department of Engineering, Cambridge University.
- Philip Stott, professor emeritus of biogeography at the University of London.
- Judith Curry, professor and former chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology.
- Robert E. Davis, Professor of Environmental Sciences at the University of Virginia.
- Joseph D'Aleo, past Chairman American Meteorological Society's Committee on Weather Analysis and Forecasting, former Professor of Meteorology, Lyndon State College.
- Freeman Dyson, professor emeritus of the School of Natural Sciences, Institute for Advanced Study; Fellow of the Royal Society.
- Richard Lindzen, Alfred P. Sloan emeritus professor of atmospheric science at the Massachusetts Institute of Technology and member of the National Academy of Sciences.
- Harrison Schmitt, geologist, Apollo 17 astronaut, former US senator.
- Anastasios Tsonis, distinguished professor of atmospheric science at the University of Wisconsin-Milwaukee.
Scientists arguing that global warming is primarily caused by natural processes
Graph showing the ability with which a global climate model is able to reconstruct the historical temperature record,
and the degree to which those temperature changes can be decomposed
into various forcing factors. It shows the effects of five forcing
factors: greenhouse gases, man-made sulfate emissions, solar variability, ozone changes, and volcanic emissions.
These scientists have said that the observed warming is more likely
to be attributable to natural causes than to human activities. Their
views on climate change are usually described in more detail in their
biographical articles.
- William Kininmonth, meteorologist, former Australian delegate to World Meteorological Organization Commission for Climatology.
- Jennifer Marohasy, an Australian biologist, former director of the Australian Environment Foundation.
- Timothy Ball, historical climatologist, and retired professor of geography at the University of Winnipeg.
- Ian Clark, hydrogeologist, professor, Department of Earth Sciences, University of Ottawa.
- Tad Murty, oceanographer; adjunct professor, Departments of Civil Engineering and Earth Sciences, University of Ottawa.
- Tim Patterson, paleoclimatologist and professor of geology at Carleton University in Canada. Ian Plimer, professor emeritus of mining geology, the University of Adelaide.
- Jan Veizer, environmental geochemist, professor emeritus from University of Ottawa.
- Henrik Svensmark, physicist, Danish National Space Center.
- Vincent Courtillot, geophysicist, member of the French Academy of Sciences.
- Nir Shaviv, professor of physics focusing on astrophysics and climate science at the Hebrew University of Jerusalem.
- Victor Manuel Velasco Herrera, Theoretical Physicist and Researcher, Institute of Geophysics of the National Autonomous University of Mexico.
- Doug Edmeades, soil scientist, officer of the New Zealand Order of Merit.
- Ole Humlum, professor of geology at the University of Oslo.
- Khabibullo Abdusamatov, astrophysicist at Pulkovo Observatory of the Russian Academy of Sciences.
- Wibjörn Karlén, professor emeritus of geography and geology at the University of Stockholm.
- Tom Segalstad, geologist; associate professor at University of Oslo.
- Sallie Baliunas, retired astrophysicist, Harvard-Smithsonian Center for Astrophysics.
- David Douglass, solid-state physicist, professor, Department of Physics and Astronomy, University of Rochester.
- Don Easterbrook, emeritus professor of geology, Western Washington University.
- William Happer, physicist specializing in optics and spectroscopy; emeritus professor, Princeton University.
- David Legates, associate professor of geography and director of the Center for Climatic Research, University of Delaware.
- Anthony Lupo, professor of atmospheric science at the University of Missouri.
- Arthur B. Robinson, American politician, biochemist and former faculty member at the University of California, San Diego.
- Murry Salby, atmospheric scientist, former professor at Macquarie University and University of Colorado.
- Nicola Scafetta, research scientist in the physics department at Duke University.
- Fred Singer, professor emeritus of environmental sciences at the University of Virginia.
- Willie Soon, astrophysicist, Harvard-Smithsonian Center for Astrophysics.
- Roy Spencer, meteorologist; principal research scientist, University of Alabama in Huntsville.
- George H. Taylor, retired director of the Oregon Climate Service at Oregon State University.
Scientists arguing that the cause of global warming is unknown
These scientists have said that no principal cause can be ascribed to
the observed rising temperatures, whether man-made or natural.
- Claude Allègre, French politician; geochemist, emeritus professor at Institute of Geophysics (Paris).
- Antonino Zichichi, emeritus professor of nuclear physics at the University of Bologna and president of the World Federation of Scientists.
- Pål Brekke, solar astrophysicist, senior advisor Norwegian Space Centre.
- Syun-Ichi Akasofu, retired professor of geophysics and founding director of the International Arctic Research Center of the University of Alaska Fairbanks.
- Robert Balling, a professor of geography at Arizona State University.
- John Christy, professor of atmospheric science and director of the Earth System Science Center at the University of Alabama in Huntsville, contributor to several IPCC reports.
- Petr Chylek, space and remote sensing sciences researcher, Los Alamos National Laboratory.
- David Deming, geology professor at the University of Oklahoma.
- Stanley B. Goldenberg a meteorologist with NOAA/AOML's Hurricane Research Division.
- Keith E. Idso, botanist, former adjunct professor of biology at Maricopa County Community College District and the vice president of the Center for the Study of Carbon Dioxide and Global Change.
- Kary Mullis, 1993 Nobel laureate in chemistry, inventor of the polymerase chain reaction (PCR) method.
Scientists arguing that global warming will have few negative consequences
These scientists have said that projected rising temperatures will be
of little impact or a net positive for society or the environment.
- Indur M. Goklany, electrical engineer, science and technology policy analyst for the United States Department of the Interior.
- Craig D. Idso, geographer, faculty researcher, Office of Climatology, Arizona State University and founder of the Center for the Study of Carbon Dioxide and Global Change.
- Sherwood B. Idso, former research physicist, USDA Water Conservation Laboratory, and adjunct professor, Arizona State University.
- Patrick Michaels, senior fellow at the Cato Institute and retired research professor of environmental science at the University of Virginia.
Deceased scientists
These scientists published material indicating their opposition to
the mainstream scientific assessment of global warming prior to their
deaths.
- August H. "Augie" Auer Jr. (1940–2007), retired New Zealand MetService meteorologist and past professor of atmospheric science at the University of Wyoming.
- Reid Bryson (1920–2008), emeritus professor of atmospheric and oceanic sciences, University of Wisconsin–Madison.
- Robert M. Carter (1942–2016), former head of the School of Earth Sciences at James Cook University.
- Chris de Freitas (1948–2017), associate professor, School of Geography, Geology and Environmental Science, University of Auckland.
- Vincent R. Gray (1922–2018), New Zealand physical chemist with expertise in coal ashes.
- William M. Gray (1929–2016), professor emeritus and head of the Tropical Meteorology Project, Department of Atmospheric Science, Colorado State University.
- Yuri Izrael (1930–2014), former chairman, Committee for Hydrometeorology (USSR); former director, Institute of Global Climate and Ecology (Russian Academy of Science); vice-chairman of IPCC, 2001–2007.
- Robert Jastrow (1925–2008), American astronomer, physicist, cosmologist and leading NASA scientist who, together with Fred Seitz and William Nierenberg, established the George C. Marshall Institute.
- Harold ("Hal") Warren Lewis (1923–2011), emeritus professor of physics and former department chairman at the University of California, Santa Barbara.
- Frederick Seitz (1911–2008), solid-state physicist, former president of the National Academy of Sciences and co-founder of the George C. Marshall Institute in 1984.
