Links Between Teleconnection Patterns and Mean Precipitation in Africa and the Arabian Peninsula From 1903 to 2023

Abstract

Changes in the seasonality and magnitude of precipitation are complex. Under global warming, this change can pose significant threats to regional water and food security. Therefore, to effectively propose any mitigation strategies, it is necessary to conduct a long-term study of changes in precipitation and associated atmospheric circulation patterns. For this purpose, the climate research unit (CRU) precipitation data set was used to investigate the trends and changes over Africa and the Arabian Peninsula from 1903 to 2023. The Mann–Kendall test analysis was used to identify the changes in precipitation trends and their significance. The Pearson correlation and Granger causality of precipitation and associated eight (8) teleconnection drivers that are shown to exhibit decadal variability such as the Interdecadal Pacific Oscillation (IPO), the Pacific Decadal Oscillation (PDO), the Atlantic Multidecadal Oscillation (AMO), the Indian Ocean Dipole (IOD), the El Niño-Southern Oscillation (ENSO), the Atlantic Meridional Mode (AMM), the North Atlantic Oscillation and the Scandinavian Pattern (SCA) were also investigated. The results show precipitation is highly heterogeneous, with patterns shaped by distinct spatial gradients and regional contrasts. West and Central Africa (North and Southern Africa) exhibited the highest (lowest) precipitation amounts. Precipitation anomalies showed pronounced decadal-scale variability, which is characterised by wet periods and prolonged dry spells across Africa, highlighting the hydroclimatic regimes. The standardised precipitation anomalies indicate that the wettest conditions occurred in the periods 1903–1912, 1925–1939, 1951–1970 and 2000—2022, while the driest conditions occurred in the periods 1913–1924, 1940–1950, 1971–1985 and 1986–1999. The area average of precipitation showed various tendencies with the season at each climate zone. All teleconnection indices exhibited weak to strong correlations (r = 0.30–0.80) of African precipitation, with IOD, PDO and AMO standing out for their strong correlations (r ≥ 0.50) and significant Granger causality across all lags, confirming their prolonged influence while AMM and SCA exhibited mild to strong correlations with causality limited to few lags, indicating a delayed influence. In contrast, for the ENSO, while mildly correlated (r ≈ 0.42), it showed no causal effect, suggesting its influence may be indirect. Furthermore, precipitation variability has strong teleconnections to global sea surface temperature (SST) patterns, specifically variations in the Atlantic (tropics and north) and Pacific (north and eastern) SST. This study contributes to precipitation dynamics in Africa and improves our understanding of precipitation–teleconnection relationships in a changing climate.