Univariate and Multivariate Analysis of Major Drought Types Over Mahanadi and Godavari River Basins in Central India
摘要
Drought is one of the most catastrophic and poorly understood natural dangers, with far-reaching implications for water supplies, ecosystems, agriculture, and human well-being. This study focuses on the Mahanadi and Godavari River Basins, where droughts occur with worrying regularity, hurting millions. We use an integrated strategy to estimate and assess meteorological, hydrological, soil moisture, and vegetation droughts from 1982 to 2013. A univariate analysis was first performed on each drought parameter separately. However, as drought has multiple drivers, univariate results were not successful to show the complex drought scenario in the river basins. Hence, bivariate analysis using copula-based approach was carried out which showcased the relationships between the drivers responsible for the complex drought scenario more effectively. Key indicators, such as the Standardized Precipitation Index (SPI), Standardized Runoff Index (SRI), Standardized Soil Moisture Index (SSI), and Vegetation Condition Index (VCI), were used to analyse the spatiotemporal distribution, frequency, duration, and area extent of these droughts. Our findings show that hydrological and soil moisture droughts are extremely severe in these river basins. While meteorological droughts have increased in area, the intensity and spread of hydrological and soil moisture droughts have reduced over time, indicating the influence of better water management methods or natural variability. This extensive analysis sheds light on the emergence and interplay of several drought types in these river basins, providing a framework for more effective drought mitigation efforts.