أثر التضاريس على تباين التساقط المطري ما بين المناطق الجبلية والسهلية في شمالي العراق

الملخص EN

Terrain is one of the most important factors affecting on the variation in the amount of rainfalls anywhere in the world, as clearly visible in the study area.

the present research is to highlight the variation in the amounts of rainfall in the mountainous and plain areas of the Northern governorates in Iraq.

the results show a gradual increase in the amounts of rain from southwest to northeast of the study area, where the increase is proportional to the increase in distance and altitude.

and by comparison between the three time periods of the study area stations, it is found that there is a very clear general trend towards a decrease in the values of rainfalls during the second period in all stations of the study area in the mountainous and plain areas.

during the third period, a difference appears between the stations, some of which recorded an increase in precipitation values, whereas others recorded a continuous decrease during this period, and others show stability in the values of rainfall.

after applying the standard deviation equation, it is observed that there is a positive relationship between the average annual rainfall and the standard deviation, as the more rain rates increase, the increase in the standard deviation; and the standard deviation gradually increases as we move away from plain areas and approach mountainous areas due to the increase in rainfall amounts in upland areas.

after applying the equation of the fluctuation coefficient in the values of rainfall, it becomes clear that there is an inverse relationship between the rates of rainfall and the rates of rain fluctuation.

as the higher the annual rainfall rates, the lower the fluctuation coefficient and the opposite is correct.

in general, the coefficient of oscillation decreases gradually heads towards the northeast of the study area.

by applying the correlation coefficient equation to measure the relationship of rainfall to height, the correlation coefficient is (0.7) indicating a strong correlation between precipitation and height.