Monster Seminar JAM - Global Climate Change and Drought in the West
Dr. Kevin E. Trenberth, Climate and Global Dynamics Division, National Center for Atmospheric Research
AbstractSince 1970 the Earth has been warming from effects of human activities. Claims to the contrary are not credible. Atmospheric composition is changing and carbon dioxide is one third higher than pre-industrial levels. Global surface temperatures today are 0.75¿C warmer than at the beginning of the 20th Century and over 0.5¿C above values in the mid-1970s, as land has warmed at double the sea surface rate. Ten of the last 11 years are the warmest on record. Global ocean temperatures are rising and ocean expansion accounts for over half the rise in global sea level of 37 mm in the past 13 years. Melting glaciers and land ice account for 1 mm/year of sea level rise, and snow cover and Arctic sea ice extent are decreasing. Water vapour has risen about 4% over the oceans since the 1970s and is a key reason for widespread observed increases in intensity of precipitation and risk of floods. Hurricanes are more intense and lasting longer, and droughts have increased in intensity and extent, especially in the subtropics and in the West of the U.S. All these vital signs are consistent with a warming climate.
University of Washington
Date and Time:
May 25, 2006,
11:00 am - 12:30 pm