Section 3 Remote sensing of global change Air pollution Global Change Instructor: Dr. Cheng-Chien LiuCheng-Chien Liu Department of Earth Sciences National Cheng Kung University Office: Building of Earth Sciences, room Voice: ext Office hours: Monday 14:00 – 17:00, Wednesday 9:00 – 12:00 URL: Last updated: 25 April 2005

Introduction  Sources of aerosol Nature  Volcano  Dessert  soil dust  Sea  sea salt aerosol Man-made  Industrial dust  Soot  Sulfate  Nitrate

Characteristics  Diameter: – 10  m For climate change: 0.1 – 1  m  Cloud condensation nuclei  Cooling Absorption Scattering  Short lifespan and local effect

Influences on climate  Short term and local  Cooling If stop consuming fuel  Aerosol , but the remaining greenhouse gasses keeps warming the earth  T  ?!!!  GG   T  Two contradictions:  CO 2  after Industrial revolution (18) but T  (1900’s)  GG  (1950’s) but T 

Black carbon contributes to droughts and floods in china  Recent paper of Science In a paper appearing in the September 27 issue of SCIENCE, Surabi Menon of NASA and Columbia University, and her colleague, James Hansen of NASA's Goddard Institute for Space Studies, New York, indicate that black carbon can affect regional climate by absorbing sunlight, heating the air and thereby altering large scale atmospheric circulation and the hydrologic cycle.  A short video of flooding in China flood60.mpghttp://svs.gsfc.nasa.gov/vis/a000000/a002500/a002560/ flood60.mpg

Black carbon contributes to droughts and floods in china (cont.)  Three conclusions Soot changes ground temperatures in Asia Soot intensifies flooding and droughts in Asia Sunblock reduces crop yields

Fig. 1 Fig. 1 Soot changes ground temperatures in Asia. Source:

Fig. 2 Fig. 2 Soot intensifies flooding and droughts in Asia. Source:

Fig. 3 Fig. 3 Sunblock reduces crop yields. Source:

Questions  What are the different influences on climate change between greenhouse gasses and aerosol?