Assessment of Standard Anomaly Index (SAI) of Last 30 Years Spaceborne Precipitation Data of Uttarakhand
摘要
Drought indices are simple mathematical tools formulated to indicate the magnitude of change in precipitation from the standard values. Many indices are being used for this purpose but have a common idea about the deflection of average data values from the standard deviation. The standardized Anomaly Index (SAI) is one such index that helps to understand the pattern of precipitation. In this present study, SAI was computed using CHIRPS (Climate Hazard Infrared Group Precipitation Station), daily precipitation data for the entire state for a period from 1991 to 2020. This will bring out the anomaly of precipitation in various parts of Uttarakhand from plainer regions to highly mountainous terrains. The Standard Anomaly Index (SAI) analysed the decadal, annual, seasonal, and monthly average precipitation. One interesting thing that the indices showed (negative values) is that there is a decrease in precipitation between 1998 to 2008 and then back to normal as was before 1998. The seasonal index showed a similar kind of thing and the monsoon months which we have taken as June, July, and August. Meanwhile, we can conclude that the recent decade has shown a positive indication of precipitation and show there are fewer chances of droughts in near future. Also, the SAI has been used to find the drought as well as humid years. The results suggest that recent years have seen an increase in precipitation, so, a new plan should be made to effectively handle the landslides and other disasters during monsoonal months and probable drought conditions in non-monsoonal months. The government should encourage new agricultural practices after a thorough analysis of new arising situations to obtain maximum benefit with available resources.