Study of the Conditions of Air Depressions in Determining the Intensity of Rainfalls Over Iraq

  • Yasser Ali Chagati Department of Atmospheric Science, College of Science, Mustansiriyah University, IRAQ
Keywords: Rainfall, Air depression, GrADS, Relative vorticity, Geopotential height


Due to the fact that Iraq is located in the tropical mid-latitude region, it has become necessary to study the impact of the abundant depressions and rain conditions affecting the country because of its importance in agriculture, urbanization, and the preservation of life and property. The study highlighted the prevailing frontal depressions mostly in this region, and this was done through analyzing and interpreting the maps in which the GrADS program was used and information from the mission of the Center for Tropical Rain Measurement (TRMM), where the first three torrential rainy cases addressed on January 25, 2012 were studied. And the second case on January 28, 2013, and the third case on October 28, 2015, and important points have been reached within the air depression through which to identify and predict the abundant rain condition over the country, which is in a nutshell the values of the low elevation lines clearly, the number of closed isobar lines indicating Depth of air depression, thermal slope and warm and cold thermal progress, negative anchored velocity values are a strong indication of the lifting of air to the top and the intensity of a rainstorm, the presence of sufficient humidity in the lower and upper atmosphere, a decrease in the dew value is an indication of saturation or not, the convergence of the isobar lines is indicated on the slope Strong pressure and active wind movement, as well as the convergence of isotherm lines, is an indication of strong thermal slope, which is usually near the frontal region Between warm and cold masses, the orthogonality of the isotherm lines on the isobar lines is an indication of warm or cold thermal progression and according to the characteristics of the weather system


Bridgman, H. & Oliver, J., 2006: The Global Climate System: Patterns, Processes, and Teleconnections. Cambridge: Cambridge University Press. doi:10.1017/CB O9780511817984.

Iraqi agrometeorology network, 2015: Climate of Iraq, republic of Iraq. Ministry of agriculture, =95.

Jafaar, S. I. and J. H. Kadhum, 2019: Dynamical Analysis of Severe Rain Events over Iraq Atmospheric Science. Mustansiriyah University. Msc. doi: v30i1.586.

Salman, A, S., 2017: Unidirectiontrends in daily rainfall extremes of Iraq, Theoretical and Applied Climatology, pp 1-13. doi:10.1007/s00704-017-2336-x.

Rousta et al., 2017: Decadal Spatial-Temporal Variations in The Spatial Pattern of Anomalies of Extreme Precipitation Thresholds (Case Study: Northwest Iran), journal Atmosphere, vol, 8 (135) doi:10.3390/atmos8080135.

Vries, et al., 2013: Extreme Precipitation Events in The Middle East: Dynamics of the Active Red Sea Trough, Journal of Geophysical Research: atmospheres, vol, 118, pp 7087- 108.doi:10.1002/jgrd.50569,2013.

Ramamurthy, M., 1997: Cyclones an idealized model, Department of Atmospheric Sciences, University of Illinois at Urbana-Champaign, (Gh)/guides /mtr/cyc/def.rxml.

Thomson., 2007: Atmospheric Science: Mid latitude Cyclones, Higher Education, 23pp,

Haby, J., 2006: Weather analysis and prediction charts, Meteorologist, https://www.the