Clouds and Cosmic Rays
Abstract
Variations in Earth's climate suggest that the atmosphere is capable of amplifying small changes in solar activity. One possibility is to influence the atmospheric trans- parency by changing cloud properties via cosmic ray ionisation (the latter is modulated by solar activity). Support for this idea is found from satellite observations of cloud cover. Data of low cloud amount, and low cloud top temperature from ISCCP (In- ternational Satellite Cloud Climate Project) covering the period 1983 -1994 shows a good correlation with cosmic ray flux. However, an extension of ISCCP cloud data has recently been released for the period January 1994 to December 1998. This shows a weakening of the correlation between low cloud amount and low cloud top temper- ature with cosmic rays after 1994. Comparison with independent cloud data from the SSMI instrument suggests the possible presence of long-term drifts in one or both of the cloud data sets. One limit is to correct for this drift in the ISCCP cloud data, which results in a good correlation between ISCCP low cloud amount and cosmic rays over the full period of available data (1983-1998).
- Publication:
-
EGS General Assembly Conference Abstracts
- Pub Date:
- 2002
- Bibcode:
- 2002EGSGA..27.5889S