James Hansen

The house in Denison, Iowa held nine people in three bedrooms. James Hansen was the fifth of seven children of an itinerant tenant farmer, and the way out was the University of Iowa, where he took three degrees in physics and astronomy inside James Van Allen's space science program. Van Allen pointed his students at the planets, and Hansen went to Venus. Working on radiative transfer, he asked what kept the Venusian surface so hot and what the clouds were made of, and in 1974 he and Jean Hovenier used polarized sunlight to show they were sulfuric acid. The greenhouse effect was his subject before Earth was.

He joined the Goddard Institute for Space Studies in 1967 and ran it from 1981 to 2013, building the global surface temperature record and the three-dimensional models that turned atmospheric physics into projections. On June 23, 1988, with Washington at 98 degrees and the hearing room hotter, he told a Senate committee that the earth was warmer than at any point in the instrumental record, and that NASA was 99 percent confident the cause was accumulating greenhouse gases rather than chance. The New York Times ran it on the front page the next morning.

In 2006 Hansen said NASA public affairs had been ordered to vet his interviews and press releases, and told 60 Minutes the Bush White House had edited climate language out of releases. NASA replied that it requires all employees to coordinate public statements, like other agencies. The dispute produced revised media rules, and in 2008 NASA's inspector general found its public affairs office had marginalized or mischaracterized climate science. He became an activist while still a government employee, arrested at a West Virginia mining protest in 2009 and outside the White House three times more, opposing the Keystone XL pipeline, and retiring in April 2013 after 46 years to campaign freely. That is the argument about him. Critics, some of them scientists, say advocacy spends the credibility that made him worth hearing. His answer is that the evidence obliges it.

He does not sit where the caricature puts him. Hansen argues that nuclear power is necessary to the climate problem, and in 2013 he and three other climate scientists wrote that continued opposition to it threatens the ability to avoid dangerous warming, drawing angry replies from Greenpeace and the Sierra Club. He has attacked cap-and-trade, including Obama's version, in favor of a rising carbon fee collected at the source and returned to residents in equal shares. His first book, Storms of My Grandchildren, appeared in 2009. In Juliana v. United States, filed in 2015 by 21 young plaintiffs including his granddaughter Sophie Kivlehan, he served as guardian for future generations. He is 85, and the verdict is not settled.

James Hansen's life against the full span of the corpus — the fading end marks a life still in progress.

• The composition of the clouds of Venus discovery
  With Jean Hovenier — polarized sunlight ruled out every candidate but sulfuric acid 1974
• Climate Impact of Increasing Atmospheric Carbon Dioxide other
  The Science paper that set out the CO2 warming case and the GISS temperature record 1981
• The GISS three-dimensional global climate model other
  The model behind the three emissions scenarios he carried to the Senate 1988
• Testimony to the Senate Energy and Natural Resources Committee other
  June 23 — the day climate change reached the American front pages 1988
• Storms of My Grandchildren book
  His first book, subtitled The Truth About the Coming Climate Catastrophe and Our Last Chance to Save Humanity 2009

• March 29, 1941 aged 0 Born in Denison, Iowa, the fifth of seven children of a tenant farmer Nine people shared a three-bedroom house.
• 1967 aged ~26 Takes a Ph.D. under James Van Allen and joins the Goddard Institute for Space Studies Three Iowa degrees in physics and astronomy, ending in the space science program.
• 1974 aged ~33 Establishes that the clouds of Venus are sulfuric acid With Jean Hovenier, from the polarization of reflected sunlight.
• 1981 aged ~40 Becomes director of GISS and publishes the carbon dioxide warming paper in Science
• June 23, 1988 aged 47 Tells a Senate committee that the greenhouse warming has been detected Washington reached 98 degrees. He said NASA was 99 percent confident the cause was greenhouse gases and not chance.
• 2006 aged ~65 Says NASA public affairs tried to restrict his interviews and press releases NASA denied a policy of censorship. A 2008 inspector general review found the office had marginalized climate science.
• June 23, 2009 aged 68 Arrested at a mountaintop removal protest in West Virginia Twenty-one years to the day after the Senate testimony.
• April 2013 aged 72 Retires from NASA after 46 years to campaign without constraint He had been arrested outside the White House that February over the Keystone XL pipeline.
• 2015 aged ~74 Joins Juliana v. United States as guardian for future generations His granddaughter Sophie Kivlehan was among the 21 young plaintiffs. The case was dismissed in 2020.

• Charles David Keeling 1928–2005
  Measured atmospheric carbon dioxide at Mauna Loa from 1958 until his death, producing the Keeling Curve. built on the record of
• Roger Revelle 1909–1991
  Oceanographer and early scientist of human-caused global warming followed
• Al Gore b. 1948
  Vice president and 2000 presidential candidate who became a leading advocate for climate policy. testified before
• Carl Sagan 1934–1996
  Astronomer and science communicator who brought cosmology to millions through Cosmos and popular books. took up his Venus problem