John Christy

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John R. Christy is a climate scientist whose chief interests are global climate change, satellite sensing of global climate, and paleoclimate.

[edit] Celebrity

He is best known, jointly with Roy Spencer, for his version of the satellite temperature record.

[edit] Status and views

He is a professor of atmospheric science and director of the Earth System Science Center at the University of Alabama in Huntsville (UAH). He was appointed Alabama's State Climatologist in 2000. For his development of a global temperature data set from satellites he was awarded NASA's Medal for Exceptional Scientific Achievement, and the American Meteorological Society's "Special Award."^[1] In 2002, Christy was elected Fellow of the American Meteorological Society.^{[citation needed]}

Christy was a lead author for the 2001 report by the Intergovernmental Panel on Climate Change^[2] and the US CCSP report Temperature Trends in the Lower Atmosphere - Understanding and Reconciling Differences.^[3] He received his Ph.D. in Atmospheric sciences from the University of Illinois. He also has a master's degree in divinity from Golden Gate Baptist Theological Seminary.

Christy is generally considered a contrarian on some issues related to global warming, although he helped draft and signed the American Geophysical Union statement on climate change.^[4] In an interview with National Public Radio about the new AGU statement, he said: It is scientifically inconceivable that after changing forests into cities, turning millions of acres into irrigated farmland, putting massive quantities of soot and dust into the air, and putting extra greenhouse gases into the air, that the natural course of climate has not changed in some way.

More recently, in a publication in the series Washington Roundtable on Science and Public Policy he said:^[5]

• "I showed some evidence that humans are causing warming in the surface measurements that we have but it is not the greenhouse relation."

• Christy has also said that while he supports the AGU declaration, and is convinced that human activities are a cause of the global warming that has been measured, he is "still a strong critic of scientists who make catastrophic predictions of huge increases in global temperatures and tremendous rises in sea levels."^[4]

Comparison of ground based (blue) and satellite based (red: UAH; green: RSS) records of temperature variations since 1979. Trends plotted since January 1982.

The climate trend shown by the UAH satellite data has changed through time, due to corrections in the processing and as the climate has varied. During the first several years of data collection the global trend was downward. That has since changed and the most recent long-term average global climate trend seen in the satellite data is +0.134 C (about 0.241° Fahrenheit) per decade.

Unlike some other major climate data sets, the satellite data are constantly being refined and adjusted as new discoveries are made in the relatively new science of remote sensing. Notable adjustments were made to compensate for the effects of orbital drift and orbital decay, and most recently to correct an arithmetic error. Christy and Spencer use intercalibration between instruments on different satellites to adjust for instrument bias, then try to validate their data by comparing it to data gathered by weather balloons and surface stations.

A native of Fresno, CA (where he learned to pan for gold), Christy was a missionary in Kenya for two years. After earning his divinity degree he founded a Southern Baptist church in South Dakota before pursuing a career in science and teaching.

[edit] Quotes

In The Great Global Warming Swindle documentary, Christy is quoted as saying, "I've often heard it said that there's a consensus of thousands of scientists on the global warming issue and that humans are causing a catastrophic change to the climate system. Well I am one scientist, and there are many that simply think that is not true."^[6]

[edit] Awards

1. 1991: NASA Exceptional Scientific Achievement Medal (with Roy Spencer)^[1]
2. 1996: AMS Special Award "for developing a global, precise record of earth's temperature from operational polar-orbiting satellites, fundamentally advancing our ability to monitor climate." (with Roy Spencer)^[1]

[edit] Selected Publications

• Hansen, J.; Sato, M.; Nazarenko, L.; Ruedy, R.; Lacis, A.; Koch, D.; Tegen, I.; Hall, T.; et al. (2002), “Climate forcings in Goddard Institute for Space Studies SI2000 simulations”, Journal of Geophysical Research 107 (D18): 2-1;2-37, doi:10.1029/2001JD001143, <http://apollo.eas.gatech.edu/yhw/publications/hansen_etal_2002.pdf> 
• Spencer, Roy W. & Christy, John R. (1990), “Precise Monitoring of Global Temperature Trends from Satellites”, Science 247 (4950): 1558-1562, <http://adsabs.harvard.edu/abs/1990Sci...247.1558S> 
• Christy, John R.; Spencer, Roy W. & Braswell, William D. (1999), “MSU Tropospheric Temperatures: Dataset Construction and Radiosonde Comparisons”, Journal of Atmospheric and Oceanic Technology 17 (9): 1153–1170, <http://ams.allenpress.com/archive/1520-0426/17/9/pdf/i1520-0426-17-9-1153.pdf> 
• Dutton, E.G. & Christy, J.R. (1992), “Solar radiative forcing at selected locations and evidence for global lower tropospheric cooling following the eruptions of El Chichon and Pinatubo”, Geophysical Research Letters 19 (23): 2313-2316, <http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=6999439> 
• Christy, John R.; Spencer, Roy W.; Norrisa, William B.; Braswella, William D. & Parker, David E. (2003), “Error Estimates of Version 5.0 of MSU–AMSU Bulk Atmospheric Temperatures”, Journal of Atmospheric and Oceanic Technology 20 (5): 613–629, <http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2F1520-0426(2003)20%3C613%3AEEOVOM%3E2.0.CO%3B2> 

[edit] References

1. ^ ^{a b c} John R. Christy: Short Biography. NASA. Retrieved on 2007-04-04.
2. ^ Appendix III - Contributors to the IPCC WGI Third Assessment Report. IPCC (2001). Retrieved on 2007-04-04.
3. ^ Wigley, Tom M.L.; V. Ramaswamy, J.R. Christy, J.R. Lanzante, C.A. Mears, B.D. Santer, C.K. Folland (April 2006). Temperature Trends in the Lower Atmosphere: Steps for Understanding and Reconciling Differences. Climate Change Science Program. Retrieved on 2007-04-04.
4. ^ ^{a b} Perlman, David. "Earth warming at faster pace, say top science group's leaders", San Francisco Chronicle, December 18, 2003, pp. A-6. Retrieved on 2007-04-04. 
5. ^ Washington Roundtable on Science and Public Policy: Satellite Temperatures by John Christy & Roy Spencer (PDF). George C. Marshall Institute (April 17,2006). Retrieved on 2007-04-04.
6. ^ Martin Durkin (director). (2007, March 8). The Great Global Warming Swindle [Documentary]. United Kingdom: WAGtv Ltd. for Channel 4. Retrieved on 2007-04-04. Event occurs at 00:03:56-00:04:09.

[edit] External links

• Homepage
• Royale, Elizabeth (2001-02-01). The Gospel According to John. Discover Magazine. Retrieved on 2007-05-26.
• 1997 hearing before the Senate Committee on Environment and Public Works
• Christy's Satellite Data
• No consensus on IPCC's level of ignorance, BBC News 13 November 2007
• John Christy connections on exxonsecrets.org