APRIL 16, 2008

JAMES R. ARNOLD LECTURE Friday, May 9, 2008 5:00PM Robinson Complex Auditorium, Graduate School of International Relations and Pacific Studies (IR/PS), UCSD
An endowed lectureship has been established to honor Professor James R. Arnold, one of UCSD's first faculty members and the founding chair of the Chemistry Department. The seventh James R. Arnold Lecture will be given by Professor Lonnie Thompson, Distinguished University Professor, School of Earth Sciences, The Ohio State University. Professor Thompson is one of the world's foremost authorities on paleoclimatology and glaciology and will discuss the current and present danger posed by ongoing climate change as well as the human response to this danger. The event will be held at the University of California, San Diego (UCSD) campus at the Graduate School of International Relations and Pacific Studies (IR/PS) in the Robinson Complex Auditorium at 5:00PM on Friday, May 9th. A light reception will follow immediately after the lecture.
This lecture is free and open to the public. UCSD Parking permits are required to park on campus, you can purchase a permit at one of the many meters located at the parking structures. For more information and directions please see the web page:
http://calspace.ucsd.edu/casgc/JArnoldLecture/Home.html
Or contact Tehseen Lazzouni at (858) 822-1597 or tlazzouni@ucsd.edu.
ABSTRACT: Glaciers are among the first responders to global warming, serving both as indicators and drivers of climate change. Over the last 30 years the Ice Core Paleoclimate Research Group at The Ohio State University has been engaged in a program of systematic recovery of ice cores from high-elevation, low-latitude ice fields. The resulting climate records, along with other proxy data, have produced three primary lines of evidence for past and present abrupt climate change. First, high-resolution time series of stable oxygen isotopes (temperature proxies) and net balance (precipitation proxies) demonstrate that the current warming at high elevations in the mid- to lower latitudes is unprecedented for at least the last two millennia. Second, the continuing retreat of most mid to low-latitude glaciers, many having persisted for thousands of years, signals a recent and abrupt change in the Earth's climate system. Finally, there is strong evidence within and around glaciers for a widespread and spatially coherent abrupt event ~5.2 ka that marked the transition from early Holocene warmth to cooler conditions that occurred through much of the world and was coincident with structural changes in several civilizations. Together, these three lines of evidence argue that the present warming and associated glacier retreat are unprecedented in many areas for at least 5000 years.
Specific evidence of recent acceleration in the rates of ice loss of glaciers will be presented. The current melting of these ice fields is consistent with model predictions of both high latitude and vertical amplification of temperatures in the tropics. The ongoing rapid, global-scale retreat of mountain glaciers is not only contributing to global sea level rise, but threatening fresh water supplies in many of the world's most populous regions. The current and present danger posed by ongoing climate change and the human response will be discussed.
SPEAKER BIO: Lonnie G. Thompson is one of the world's foremost authorities on paleoclimatology and glaciology. He has led more than 50 expeditions during the last 30 years, conducting ice-core drilling programs in the world's polar regions as well as in tropical and subtropical ice fields.
Recently, Thompson and his team developed lightweight solar-powered drilling equipment for the acquisition of histories from ice fields in the high Andes of Peru and on Mount Kilimanjaro in Tanzania. The results of these histories, published in more that 200 articles, have contributed greatly toward the understanding of the Earth's past, present and future climate system. Other Thompson-led expeditions have recovered a 460-meter-long ice core, the world's longest from a mountain range (Alaska, 2002); the first tropic ice core (Peru, 1983); and cores containing the entire sequence of the Last Glacial Stage as well as cores dating over 750,000 years in age, the oldest outside the polar regions (Tibet, 1992).
Thompson's research has resulted in major revisions in the field of paleoclimatology, in particular, by demonstrating how tropical regions have undergone significant climate variability, countering an earlier view that higher latitudes dominate climate change. Thompson has received numerous honors and awards. In 2005, he was elected to the National Academy of Sciences and was awarded the John and Alice Tyler Prize for Environmental Achievement. He has been selected by Time magazine and CNN as one of "America's Best" in science and medicine. His research has been featured in hundreds of publications, including National Geographic and the National Geographic Adventure magazines.
Thompson and his team are the subject of a new book entitled: Thin Ice: Unlocking the Secrets of Climate in the World's Highest Mountains by Mark Bowen published in late 2005. In 2006, he was elected member of the American Philosophical Society, Alumni member of Phi Beta Kappa and chosen to receive the Roy Chapman Andrews Society 2007 Distinguished Explorer Award. He served as Contributing Author on Chapter 6: Paleoclimate IPCC AR4 WG, 2007 volume. In 2007, he was awarded both the Seligman Crystal, the highest professional award in Glaciology and the National Medal of Science, the highest honor that the United States can give to an American scientist.
Professor Thompson's Ice Core Paleoclimatology Research Group website can be found at:
http://bprc.osu.edu/Icecore/