Observed Spatio Temporal Trends of Precipitation and Temperature Over Afghanistan

Afghanistan is a semi-arid country and most vulnerable to climate extremes related hazards, including droughts and floods that has caused huge impact on the socio-economic development of the country. The present study analysed the observed precipitation and temperature trends for seven agro-climatic zones of Afghanistan over the period 1951 to 2007 with Asian Precipitation-Highly-Resolved Observational Data Integration towards Evaluation of Water Resources (APHRODITE). Change in the magnitude of precipitation and temperatures in recent years with reference to distant past was assessed by dividing the historical data into two parts as 1951–1990 and 1991–2006. Further, the trend analysis was performed on daily data to test the increasing or decreasing rainfall and temperature trends using Mann–Kendall trend test for each zone of Afghanistan. The maximum precipitation occurrence months were observed as January, February, March, April and May for all zones of Afghanistan. Whereas, June, July, August, September, October, November and December and generally considered as dry months. The maximum temperature was observed in the months of May, June, July and August, with hottest month as July for all seven zones of Afghanistan. The annual total precipitation has shown an increasing trend for the zones of South, South-West, East and Central, whereas, a decreasing trend has been observed for the zones of North, North-East and West zones. The trend analysis of the precipitation with gridded data sets reveals for most part of the Afghanistan region the rainfall has been observed as decreasing. Whereas, for all seven agro-climatic zones of Afghanistan an increasing trend of temperature in recent years of 2004 to 2016 were observed. Overall, the North, North-East and West zones of Afghanistan are more vulnerable with decreasing precipitation and increasing temperatures indicating more dry and warm periods indicating increasing drought conditions. Whereas, the South, South-West, East, and Central zones are more vulnerable with increasing trends of both precipitation and temperatures indicating increase of more wet and warm climates.