Impact of North-South Shift of Azores High on Summer Precipitation over North West Europe

Shahnaz Ali Rashid, Muhammad J. Iqbal, Muhammad A. Hussain

Department of Mathematics, University of Karachi, Karachi, Pakistan.
Department of Sciences & Humanities, National University of Computer & Emerging Sciences (FAST), Karachi, Pakistan.
Institute of Business and Technology, Karachi, Pakistan.

DOI: 10.4236/ijg.2012.325099                

Abstract

Several Studies demonstrate that North Atlantic Oscillation (NAO) influences variability of climate over Europe. As NAO is has significant influence on climate of Europe during boreal cold season (November to April), we use the centers of action approach for the study of summer precipitation (June to August) variability over Europe, taking into account variations in the components of the NAO North Atlantic Oscillation (NAO), the Azores High and the Icelandic Low pressure systems. This study shows that north-south shifts of the Azores High has significant impact on interannual variations of summer precipitation over North West Europe, there being more precipitation when the Azores High shifts southward versus when it is northward. Thus this article demonstrate that when the Azores High system is to the south there is flux of moist and warm air from the Atlantic into NW Europe. We present a regression model for summer precipitation over North-west in which the Azores High latitude and the Icelandic low longitude are independent variables and it explains 53 percent of the variance of precipitation during 1952-2002, a significant enhancement over the NAO value of R² = 0.10.

Keywords

NAO; COA; Azores High Pressure; Icelandic Low Pressure

Conflicts of Interest

The authors declare no conflicts of interest.

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