Assessing and forecasting droughts in eThekwini municipality: SPI, SPEI, and Time Series Insights for Sustainable Resource Management

Ntokozo Xaba; Nirmala Deenadayalu

doi:10.36096/ijbes.v7i4.869

Authors

Ntokozo Xaba Faculty of Applied Science, Durban University of Technology, South Africa https://orcid.org/0000-0002-1446-9024
Nirmala Deenadayalu Durban University of Technology, South Africa

DOI:

https://doi.org/10.36096/ijbes.v7i4.869

Keywords:

Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), Meteorological Drought, SARIMA.

Abstract

The eThekwini Municipality, South Africa, has experienced increased drought frequency and intensity due to climate change and the El Niño-Southern Oscillation (ENSO). This study assesses and forecasts meteorological, agricultural, and hydrological droughts using the Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), and ARIMA/SARIMA models, analyzing climate data from 1990 to 2022. Results reveal significant drought intensification, with extreme events in 2019 (central region, SPEI-6 = -3.42) and 2020 (northern region, SPI-3 = -8.15). SARIMA models outperformed ARIMA in forecasting accuracy, emphasizing the role of seasonality. Urbanization and land-use changes exacerbate central region droughts, while northern agricultural reliance highlights the need for water storage. Recommendations include drought-resistant crops, enhanced irrigation, and rainwater harvesting to bolster resilience. These findings inform localized drought management and contribute to global climate adaptation strategies.

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