Publications

Mallick, J; Alqadhi, S; Alsubih, M; Othman, A (2025). Multi-scale analysis of vegetation response to drought dynamics in Saudi Arabia. THEORETICAL AND APPLIED CLIMATOLOGY, 156(6), 350.

Abstract
Understanding drought dynamics is essential for effective climate adaptation in arid regions. This study presents a multi-scale spatiotemporal analysis of drought characteristics and vegetation response across Saudi Arabia from 2000 to 2023, using the Standardized Precipitation Evapotranspiration Index (SPEI) at 2-, 3-, 6-, and 12-month time scales and MODIS-derived NDVI data. Results indicate increasing drought severity, particularly in central and northern regions, with SPEI-12 values frequently dropping below -1.5 during major drought years such as 2003, 2008, and 2016. Drought duration analysis using Run theory reveals that many regions experienced multi-month drought spells, with some extending beyond five consecutive 16-day periods, highlighting their persistence. The intensity of drought events, measured as the cumulative deficit below the threshold, was also found to be significantly higher during long-term drought phases. Vegetation health, assessed through NDVI, showed strong negative correlations with longer-scale SPEI values, confirming the lagged and cumulative impact of prolonged drought. Wavelet analysis further identified dominant drought cycles in the 2-4 and 8-12 year bands, revealing the influence of both short-term variability and long-term climatic oscillations. These findings provide valuable insights for drought monitoring, early warning systems, and climate-resilient land management strategies in hyper-arid environments.

DOI:
10.1007/s00704-025-05580-2

ISSN:
1434-4483