tailieunhanh - Deep solar minimum and global climate changes

This paper examines the deep minimum of solar cycle 23 and its potential impact on climate change. In addition, a source region of the solar winds at solar activity minimum, especially in the solar cycle 23, the deepest during the last 500 years, has been studied. Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activity are so weak and hence expected to cause global cooling. Prevalent global warming, caused by building-up of green-house gases in the troposphere, seems to exceed this solar effect. This paper discusses this issue. | Journal of Advanced Research 2013 4 209-214 Cairo University Journal of Advanced Research REVIEW Deep solar minimum and global climate changes Ahmed A. Hady Astronomy Space Meteorology Department Faculty of Sciences Cairo University Giza Egypt Received 16 May 2012 revised 22 October 2012 accepted 1 November 2012 Available online 18 February 2013 KEYWORDS Deep solar minimum Solar activity Climate change Global cooling Abstract This paper examines the deep minimum of solar cycle 23 and its potential impact on climate change. In addition a source region of the solar winds at solar activity minimum especially in the solar cycle 23 the deepest during the last 500 years has been studied. Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activity are so weak and hence expected to cause global cooling. Prevalent global warming caused by building-up of green-house gases in the troposphere seems to exceed this solar effect. This paper discusses this issue. 2013 Cairo University. Production and hosting by Elsevier . All rights reserved. Introduction Climate change has become a prominent item on the agenda of world concerns. It is a growing crisis with economic health and safety food production security and other dimensions. There is alarming evidence that important tipping points leading to irreversible change in major earth systems and ecosystems may already have been reached or passed. From 1860 to 1990 the global mean annual surface temperature increased C 1 at the same time the continuation of industrial produced CO2 gas in earth s atmosphere increased from 280 to 353 ppmv leading to the hypothesis that the warmer temperatures signify the climate system s response to CO2 gas increasing. However statistical analysis of climate records reveals significant inter-annual and inter-decadal variability suggesting that the cause of the warming is more complex than the influence of increasing greenhouse gases alone. Tel. 20 1001833361 .