Description:

EVENT: JAMES R. ARNOLD LECTURE

"Global Climate Change: A Paleoclimate
Perspective from the World's Highest Mountains"

by Lonnie Thompson
DATE: Friday, May 9, 2008
TIME: 5:00 - 7:00 PM

Reception and Refreshments Following

LOCATION:
Robinson Complex Auditorium
Graduate School of International Relations and Pacific Studies (IR/PS), UCSD

Directions to IRPS click here >>

If you are coming from off campus we suggest you park in the new Hopkins Parking Structure, which is closer to Robinson Auditorium than the Pangea Structure:
 
--Take North Torrey Pines to Northpoint Drive
--Northpoint Drive becomes Hopkins Drive
--Turn right into the Hopkins Parking Structure which has Visitor Parking available
--Take the elevator up and exit near the Social Sciences building
--Cross Ridge Walk and you’re there!

The 7th Annual 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.

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.

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.