Naslov
Forbush Decreases: No Change of Global Cloud Cover

Autori
Čalogović, Jaša ; Arnold, Frank ; Desorgher, Laurent ; Flückiger, O. Erwin ; Beer Jürg

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
International Astronomical Union (IAU) Symposium 257 on Universal Heliophysical Processes

Mjesto i datum
Janjina, Grčka, 15.09.2008. - 19.09.2008

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
cosmic rays; cloud cover; Forbush decrease; climate

Sažetak
Svensmark and Friis-Christensen analyzing one solar cycle reported 1997 that global cloud cover changed in phase with the GCR flux by 2-3%. This initiated heavy debates in the scientific community. However, up to date no really conclusive results have been published. In our approach we use the same cloud data and assumptions as previous authors, but instead of analyzing cosmic ray changes over the 11-year solar cycle we concentrate on rapid changes, so-called Forbush decreases which are comparable in amplitude but last only about a week. For each of the six selected Forbush decreases extensive Monte Carlo simulations were carried out to calculate the global change in ion production rate in the atmosphere. For each grid cell the ion production change was compared with the corresponding ISCCP D1 cloud data change allowing for time lags ranging from 0 to 10 days. Detailed global correlation analysis of these ionization data with the corresponding cloud data does not show any indication for the proposed link between cosmic ray intensity and global cloud cover.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Geologija

POVEZANOST RADA