BBVA Foundation Frontiers of Knowledge Award (2016) Tang Prize (2018) James Edward Hansen (born March 29, 1941) is an American adjunct professor directing the Program on Climate Science, Awareness and Solutions[4] of the Earth Institute at Columbia University.

[14] The program is working to continue to "connect the dots" from advancing basic climate science to promoting public awareness to advocating policy actions.

[19] By 1974, the composition of Venus' clouds had not yet been determined, with many scientists proposing a wide variety of compounds, including liquid water and aqueous solutions of ferrous chloride.

[28] Hansen countered by saying that having insider information shifted the odds to those who know the physics of the climate system, and that whether there is a new temperature record depends upon the particular data set used.

In a paper with Menon and colleagues, through the use of observations and climate models results, they conclude that the black carbon heats the air, increases convection and precipitation, and leads to larger surface cooling than if the aerosols were sulfates.

[38] A year later, Hansen teamed with Makiko Sato to publish a study on black carbon using the global network of AERONET sun photometers.

[40] Estimations of trends in black carbon emissions show that there was a rapid increase in the 1880s after the start of the Industrial Revolution, and a leveling off from 1900 to 1950 as environmental laws were enacted.

Under the alternate scenario, sea levels could rise by 1 meter per century, causing problems due to the dense population in coastal areas.

[49] A 1981 Science publication by Hansen and a team of scientists at Goddard concluded that carbon dioxide in the atmosphere would lead to warming sooner than previously predicted.

[53] The second generation of the GISS model was used to estimate the change in mean surface temperature based on a variety of scenarios of future greenhouse gas emissions.

Rahmstorf and coauthors showed concern that sea levels are rising at the high range of the IPCC projections, and that this was due to thermal expansion and not from melting of the Greenland or Antarctic ice sheets.

In a 2007 paper, Hansen discussed the potential danger of "fast-feedback" effects causing ice sheet disintegration, based on paleoclimate data.

"[66] In 2016, a team of 19 researchers led by Hansen published a paper "Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous" describing the effect of meltwater from ice sheets on the Atlantic meridional overturning circulation (slowing it or even stopping) and Antarctic bottom water formation.

And the cool fresh meltwater on the ocean close to Greenland and Antarctica leads to larger temperature difference between tropics and middle latitudes, what would enable storms as strong as in the last interglacial, the Eemian, whose evidence includes, among others, megaboulders on Bahamas.

[69] The paper also concluded that sea level rise will be greater than the IPCC estimates and one of the ocean's major circulation systems could collapse before the end of the century.

"[74] He also says that changes needed to reduce global warming do not require hardship or reduction in the quality of life, but will also produce benefits such as cleaner air and water, and growth of high-tech industries.

[81] According to Richard Besel of California Polytechnic State University, Hansen's testimony "was an important turning point in the history of global climate change.

"[82] According to Roger A. Pielke of the National Center for Atmospheric Research, Hansen's "call to action" "elevated the subject of global warming and the specter of associated impacts such as more hurricanes, floods, and heat waves, to unprecedented levels of attention from the public, media, and policy makers.

"[87][88] Citing the reactions of "several people" and "three of his scientific colleagues" as his primary motivation, Hansen stated that he certainly did not mean to trivialize suffering by the families who lost relatives in the Holocaust and then apologized, saying he regretted that his words caused pain to some readers.

[96][97][98][99][100] Hansen retired from NASA in April 2013 after 46 years of government service, saying he planned to take a more active role in the political and legal efforts to limit greenhouse gases.

In an interview on CBC television on March 3, 2015, Dr Hansen stated "The solution [to climate change] has to be a rising price on carbon and then the really dirty fuels like tar sands would fall on the table very quickly.

If we would simply put a fee on carbon – you would collect from the fossil fuel companies at the source (the domestic mines or the ports of entry) and then distribute that money to the public, an equal amount to all legal residents, that would begin to make the prices honest.

[96] In his first book Storms of My Grandchildren, similarly, Hansen discusses his Declaration of Stewardship, the first principle of which requires "a moratorium on coal-fired power plants that do not capture and sequester carbon dioxide".

[107] In March 2013, Hansen co-authored a paper in Environmental Science & Technology, entitled "Prevented mortality and greenhouse gas emissions from historical and projected nuclear power".

Looking to the future, between 2010 and 2050, it was estimated that nuclear could additionally avoid up to 420,000 to 7 million premature deaths and 80 to 240 billion tonnes of greenhouse gas emissions.

[108] This paper elicited a critical response to Kharecha and Hansen's analysis, from an international group of senior academic energy policy analysts, including Benjamin Sovacool, M.V.

[117] In June 2006, Hansen appeared on 60 Minutes stating that the George W. Bush White House had edited climate-related press releases reported by federal agencies to make global warming seem less threatening.

Hansen urged President Obama to reject the Keystone pipeline extension intended to carry more synthetic crude oil from Canada's Athabasca Tar Sands to the Gulf of Mexico.

"[123] In 2001, he received the 7th Annual Heinz Award in the Environment (endowed with US$250,000) for his research on global warming,[124] and was listed as one of Time magazine's 100 Most Influential People in 2006.

He delivered a lecture, entitled, "White House Arrest and the Climate Crisis," later that same day at Anita Tuvin Schlechter Auditorium on the college's campus.