Assessment of observed changes in drought characteristics and recent vegetation dynamics over arid and semiarid areas in Sudan.

Over the past decades, drought has been considered as one of the most catastrophic natural disasters due to the devastating implications associated with this phenomenon. This research examines drought characteristics, severity, intensity, and duration in Sudan from 1980 to 2017 using meteorological observations and remote sensing datasets. According to analyses of the standardized precipitation index (SPI) provided by 29 sites, 72% of all dry occurrences appear to have occurred during the 1980s. The wettest occurrences, on the other hand, occurred after the mid-1990s timeframe and accounted for 82% of the total. SPI-3 research over Sudan revealed dry conditions during the 1980s. Early datasets indicate extreme drought periods occurred between 1982 and 1987, while fewer occurrences were observed during the 1990s and 2000s. SPI-3 shows that rainfall increased dramatically in the 1990s. Among the understudied time scales, 1982, 1983, 1984, 1987, 1990, 1992, and 2004 regimes recorded the driest events, whereas 1988, 1998, 1999, 2000, 2003, 2005, 2006, 2007, and 2016 had the wettest. Recent seasonal vegetation conditions from the normalized difference vegetation index (NDVI) and soil moisture were examined. The intensity of severe droughts declined for 2000, 2005, 2010, 2015, and 2020 periods. Conversely, a discernible upward trend in wet conditions with corresponding increases can be observed. Findings depict a graphical illustration of changes in the vegetation condition index (VCI), both geographically and chronologically in Sudan between 2000 and 2020. Generally, a positive correlation between the SPI-12 and AMO was obtained across Sudan's different regions. Significant power association peaked between 1 and 2 and 6 and 10 years from 1980 to 1990 and 6 and 8 years from 2005 to 2017. This study lays the groundwork for future drought studies, which further provides the technical basis for policymakers to address the consequences of drought on agriculture and the economy. [ABSTRACT FROM AUTHOR]