The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here:

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Petter Pilesjö

Petter Pilesjö


Petter Pilesjö

The effect of the North Atlantic Oscillation on the Iraqi climate 1982-2000


  • Salar Ali Khidher
  • Petter Pilesjö

Summary, in English

In this study, we have analyzed the spatial and temporal correlation between the North Atlantic Oscillation (NAO) and the climate in Iraq, with a focus on precipitation, temperature, and number of Mediterranean cyclones. It was found that the influence of the NAO varies per climate indicator. For example, the influence is greater on precipitation than on temperature. One conclusion of the study is that the mean annual precipitation in Iraq increases during a negative phase of the NAO and decreases during a positive phase. In addition, the correlation between NAO and precipitation is more pronounced in the south of the country than in the middle and northern regions. Regarding the temporal correlation between NAO and precipitation, the influence of the NAO on Iraqi precipitation was found to be weak during the fall season, but to become more pronounced in the winter, culminating during the spring, and then vanishing in the summer. It was also concluded that when the NAO is in a positive phase, the area featuring a desert climate (Bwha) expands in Iraq, while the area featuring other climates decreases. During these years, both the Mediterranean climate (Csa) and the steppe climate (Bsha) cover a smaller part of the country due to the limited amount of precipitation. The opposite occurs during a negative phase of the NAO. Analysis of the number of Mediterranean cyclones that reach Iraq shows that there is no significant difference in the number of cyclones occurring during negative and positive phases of the NAO. However, there are differences in the strength of the cyclones. This study represents a first step in analyzing the relation between the NAO and the Iraqi climate and hopes to lead to further research.


  • Dept of Physical Geography and Ecosystem Science
  • Centre for Advanced Middle Eastern Studies
  • Centre for Geographical Information Systems (GIS Centre)
  • MECW: The Middle East in the Contemporary World

Publishing year







Theoretical and Applied Climatology





Document type

Journal article




  • Meteorology and Atmospheric Sciences
  • Climate Research




  • ISSN: 1434-4483