تجزيه و تحليل پديده خشكسالي كشاورزي شهرستان رامسر به روش تورنث وايت

Analysis of the agricultural drought in Ramsar by using the Thornthwaite method

Drought refers to random characteristic of natural phenomena, brought about by the irregular deficit or shortage of available water. It affects the plant growth and reduces its yield. To estimate the intensity and the frequency of droughts will help reduce the damaging effect of drought. In this study we have used the water-budget methods and Thomthwaiteʹs aridity index and its standard deviation for Ramsar duringl956-2008 to show the frequency and the intensity of drought effects in this place. Results showed that there was a normal monthly trend of the year. In this station, there is water deficit and the months that have water surplus. We found that this station every ten years will affect 3 or 4 times severe droughts and the profanity of drought is 0.4. For the year 2001 the rainfall was good but the drought effect was also severe and in the year 2002, the rainfall was less than the disastrous effect of drought.