The global warming controversy concerns the public debate over whether global warming is occurring, how much has occurred in modern times, what has caused it, what its effects will be, whether any action can or should be taken to curb it, and if so what that action should be. In the scientific literature, there is a very strong consensus that global surface temperatures have increased in recent decades and that the trend is caused by human-induced emissions of greenhouse gases. No scientific body of national or international standing disagrees with this view, though a few organizations with members in extractive industries hold non-committal positions, and some have tried to persuade the public that climate change is not happening, or if the climate is changing it is not because of human influence, attempting to sow doubt in the scientific consensus.
Patrick J. Michaels was an American agricultural climatologist. Michaels was a senior fellow in environmental studies at the Cato Institute until 2019. Until 2007, he was research professor of environmental sciences at the University of Virginia, where he had worked from 1980.
The temperature record of the last 2,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional: the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that "Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1,300 years." The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century. As of 2010 this broad pattern was supported by more than two dozen reconstructions, using various statistical methods and combinations of proxy records, with variations in how flat the pre-20th-century "shaft" appears. Sparseness of proxy records results in considerable uncertainty for earlier periods.
Sallie Louise Baliunas is a retired astrophysicist. She formerly worked at the Center for Astrophysics | Harvard & Smithsonian and was the Deputy Director of the Mount Wilson Observatory from 1991 to 2003.
The Global Warming Petition Project, also known as the Oregon Petition, is a group which urges the United States government to reject the Kyoto Protocol of 1997 and similar policies. Their petition challenges the scientific consensus on climate change. Though the group claims more than thirty-thousand signatories across various scientific fields, the authenticity and methods of the petitioners as well as the signatories' credentials have been questioned, and the project has been characterized as a disinformation campaign engaged in climate change denial.
Sherwood B. Idso is the president of the Center for the Study of Carbon Dioxide and Global Change, which rejects the scientific consensus on climate change. Previously he was a Research Physicist with the U.S. Department of Agriculture's Agricultural Research Service at the U.S. Water Conservation Laboratory in Phoenix, Arizona, where he worked since June 1967. He was also closely associated with Arizona State University over most of this period, serving as an adjunct professor in the Departments of Geology, Geography, and Botany and Microbiology. His two sons, Craig and Keith, are, respectively, the founder and vice president of the Center for the Study of Carbon Dioxide and Global Change.
James Edward Hansen is an American adjunct professor directing the Program on Climate Science, Awareness and Solutions of the Earth Institute at Columbia University. He is best known for his research in climatology, his 1988 Congressional testimony on climate change that helped raise broad awareness of global warming, and his advocacy of action to avoid dangerous climate change. In recent years, he has become a climate activist to mitigate the effects of global warming, on a few occasions leading to his arrest.
Willie Wei-Hock Soon is a Malaysian astrophysicist and aerospace engineer who was long employed as a part-time externally funded researcher at the Solar and Stellar Physics (SSP) Division of the Center for Astrophysics | Harvard & Smithsonian.
Hans von Storch is a German climate scientist. He is a professor at the Meteorological Institute of the University of Hamburg, and Director of the Institute for Coastal Research at the Helmholtz Research Centre in Geesthacht, Germany. He is a member of the advisory boards of the journals Journal of Climate and Annals of Geophysics. He worked at the Max Planck Institute for Meteorology from 1986 to 1995 and headed the Statistical Analysis and Modelling research group there.
Sonja Boehmer-Christiansen is an Emeritus Reader in the Department of Geography at the University of Hull in Kingston upon Hull England, where she taught environmental policy, management and politics. She was editor of the journal Energy & Environment from 1998 to 2017.
Philip Douglas Jones is a former director of the Climatic Research Unit (CRU) and a professor in the School of Environmental Sciences at the University of East Anglia (UEA) from 1998, having begun his career at the unit in 1976. He retired from these positions at the end of 2016, and was replaced as CRU director by Tim Osborn. Jones then took up a position as a Professorial Fellow at the UEA from January 2017.
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures.
David Russell Legates is a former professor of geography at the University of Delaware. He is the former Director of the Center for Climatic Research at the same university and a former Delaware state climatologist. In September 2020, the Trump administration appointed him as deputy assistant secretary of commerce for observation and prediction at the National Oceanic and Atmospheric Administration.
Energy & Environment is an academic journal "covering the direct and indirect environmental impacts of energy acquisition, transport, production and use". Under its editor-in-chief from 1998 to 2017, Sonja Boehmer-Christiansen, it was known for easygoing peer-review and publishing climate change denial papers. Yiu Fai Tsang became its editor-in-chief in May 2017.
Friends of Science(FoS) is a non-profit advocacy organization based in Calgary, Alberta, Canada. The organization rejects the established scientific consensus that humans are largely responsible for the currently observed global warming. Rather, they propose that "the Sun is the main direct and indirect driver of climate change," not human activity. They argued against the Kyoto Protocol. The society was founded in 2002 and launched its website in October of that year. They are largely funded by the fossil fuel industry.
Christopher Rhodes de Freitas was a New Zealand climate scientist. He was an associate professor in the School of Environment at the University of Auckland.
The Soon and Baliunas controversy involved the publication in 2003 of a review study written by the aerospace engineer Willie Soon and astronomer Sallie Baliunas in the journal Climate Research, which was quickly taken up by the George W. Bush administration as a basis for amending the first Environmental Protection Agency's Report on the Environment.
The Wegman Report was prepared in 2006 by three statisticians led by Edward Wegman at the request of Rep. Joe Barton of the United States House Committee on Energy and Commerce to validate criticisms made by Stephen McIntyre and Ross McKitrick of reconstructions of the temperature record of the past 1000 years, in particular the reconstructions by Mann, Bradley and Hughes of what had been dubbed the hockey stick graph.
The North Report was a 2006 report evaluating reconstructions of the temperature record of the past two millennia, providing an overview of the state of the science and the implications for understanding of global warming. It was produced by a National Research Council committee, chaired by Gerald North, at the request of Representative Sherwood Boehlert as chairman of the U.S. House of Representatives Committee on Science.
Timothy Francis Ball was a British-born Canadian public speaker and writer who was a professor in the Department of Geography at the University of Winnipeg from 1971 until his retirement in 1996. Subsequently Ball became active in promoting rejection of the scientific consensus on global warming, giving public talks and writing opinion pieces and letters to the editor for Canadian newspapers.
