Wind speed variation and its impact on the amount of evaporation-transpiration potential seasonal in Sulaymaniyah Baghdad, Basra Khanaqin stations adoption equation Penman

Abstract

Wind speed is one of climatic elements affecting the amount of potential evapotranspiration, no less importance in influencing potential evapotranspiration from other items, and in spite of knowledge the role of wind as a factor in the values, but it has not been a study to measure statistically this role in Iraq. Hence the aim of the research: to identify the amount of influence they wind speed variation spatial values potential evapotranspiration and temporal values of the stations studied. The study included stations (Sulaymaniyah, Khanaqin, Baghdad, and Basra) for the period of 1980/2010. And relied on simple linear regression to achieve the aim of the research. The results showed that the winds of an influential role in the occurrence of variations in the values of the potential evapotranspiration of not less important than the temperature and relative humidity. It is found that the increase in wind speed rates in effect raise the evaporation values and strength of this relationship increase in summer, as the effected of values have risen ranged between (94%- 73%) of the stations studied, while the potential evapotranspiration values in the spring less affected by wind speed for all stations the effected values ranged between (0.4%-70%) in stations Basra and Khanaqin, respectively. The spatial variations turned out to be influenced by the strength of the wind speed increases direction from south to north, as Basra, the lowest values of coefficient of determination station in all seasons ranged recorded between (0.4%- 79%), while the highest values recorded in Khanaqin to the selection coefficient ranged between (69%-93%).