Drought Monitoring Over the Northeast China Using GRACE Satellite Data from 2002 to 2016

Abstract

Drought is one of the most common natural disasters in the world. The frequent occurrence and long-term persistence of drought will result in huge losses in industrial and agricultural production. Understanding and quantification of the time and spatial dynamic patterns of drought, including the occurrence, duration and intensity, are the primary goals of the agriculture drought monitoring and yield forecasting in the agricultural region in Northeast China. Fundamentally, drought monitors rely on satellite-gauge precipitation data and temperature, yet is also depends on underground water storage, evapotranspiration and runoff. Since 2002, NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission provide a revolutionary approach to view the water stored in soil, track the movement of water and retrieve the total water storage (TWS) via weight. And the TWS change can provide the regional information of precipitation, evapotranspiration, and surface and subsurface runoff. In this study, the GRACE TWS anomaly will be revealed to Northeast China to characterize more objective identification of drought for 157 months climatology (from April 2002 to December 2016). Comparing with the drought incidents from 2002 to 2016 in the Northeast China, the result shows that the trends of GRACE TWS with months can depict the temporal and spatial characteristic of drought in the study area. According to the negative GRACE terrestrial water storage anomalies (TWSA), which can represent storage deficits, we find that severe drought happened in western part of the study area in 2003, and southern part of the study area in 2007 and 2011. The April-May average GRACE TWS noted the spring drought occurred in most part of study area in 2003, 2009, 2011 and 2012. The significant decreases of TWS from May 2007 to June 2008 reveled by GRACE TWS lead to a serious drought conditions. The five-month averages of GRACE TWS from June to October were computed in each year, and deficit during 2014 lead to an agricultural drought and crop production loss in Liaoning and Jilin provinces. However, GRACE TWS changes show no one-to-one relationship with precipitation, as the precipitation is not the primary source of TWS changes. The present result demonstrates that GRACE TWS as referenced data is capable of identify and mapping drought in the Northeast China. It will help better understand the cause of drought, and observe the occurrence, trends and spatiotemporal characteristics of drought. It would be valuable for regional water management.