A re-interpretation of impact of the Icelandic Low and Azores High on winter precipitation over Iberian Peninsula

作者：Iqbal M J; Rashid Shahnaz Feroz^*

来源：Arabian Journal of Geosciences, 2016, 9(2): 102.

DOI：10.1007/s12517-015-2086-y

• Azores High
• Icelandic Low
• Winter rainfall

Several studies show that North Atlantic Oscillation (NAO) has dominant influence on the variability of climate over Iberian Peninsula. The traditional definition of the NAO index is a very simple representation of the atmospheric state of negative correlation between the Azores High and the Icelandic Low. The NAO index does not take into account the geographically extensive nature of the high and the low pressure systems and their movements. Fluctuations in both the characteristic shapes and positions of the Azores High and the Icelandic Low influence atmospheric circulation over the north Atlantic region. We study interannual variations of winter rainfall over Iberia, taking into account variations in the Azores High and the Icelandic Low pressure systems. Analysis presented in this paper shows that the north-south migrations of the Azores High exert the greatest impact on winter precipitation over Iberian Peninsula. Using NCEP/NCAR reanalysis data, this approach allows us to understand the changes in atmospheric circulation through which latitudinal shifts of the Azores High influence regional precipitation over Iberia.

• 出版日期2016-2