Comparative analysis of interdecadal precipitation variability over central North China and sub Saharan Africa

Abstract

The interdecadal variability of precipitation over sub-Saharan Africa (SSA) and central North China (CNC) is examined and compared in this study. Previous studies have found that the two regions have similar interdecadal dry-wet evolution in the past 100 years. The results show obvious decadal precipitation fluctuations in the two regions. In CNC, a persistent negative precipitation anomaly is detected from the early 1970s to the 2000s. In SSA, a negative precipitation anomaly is apparent since the late 1970s, while a distinct upward trend is found since the 1990s although the precipitation anomaly is still negative. Significant correlation is found between the decadal precipitation anomalies in SSA and the SST modes (Atlantic Multidecadal Oscillation (AMO) and Pacific Decadal Oscillation (PDO)), as well as the North Atlantic Oscillation (NAO), while in CNC the decadal precipitation is influenced by the NAO and PDO. The EOF results show that the total explained variance of the first four EOFs in SSA is smaller than that of CNC. The fourth and third modes in SSA are significantly associated with the AMO and PDO respectively, while the first, third, and fourth modes are significantly associated with the NAO. The first mode in CNC is significantly associated with the NAO. The first mode of the precipitation anomaly in SSA fluctuates out of phase with that in CNC, while in-phase changes are apparent among the third and the fourth modes. 摘要

Vegetation Cover Change Associated With Changes in Hydro-Climatic Variables in Northern Sub-Saharan Africa in Recent Decades.

“…The NSSA experienced increases in PRE, TMP and PET, but dominated by a declining trend in SM. The increase obtained for PRE and TMP are consistent with many studies conducted over the region (Collins, 2011;Ogou et al, 2019).The atmospheric ciruculation contributed to the increase in PRE (Sindikubwabo et al, 2018). It is worth noting that the PET has increased over most parts of the area, however received less attention of researcherscompare with PRE, TMP and SM.…”

“…However, the temporal coverage of the data available for these studies was short. For instance, over the NSSA, the precipitation behaved differently regarding the length of studied period (Ogou, 2019). A longtime period of NDVI data would be more helpful to identify departures in primary production for entire ecological zones, for instance, the Sahelian zone (Tucker, 1986).…”

Review of Meteorological Drought in Africa: Historical Trends, Impacts, Mitigation Measures, and Prospects

“…Rainfall variability over the region is mostly associated with the West African monsoon, which is the advection of moisture from the Gulf of Guinea, occurring during the summer months (July to September) as a result of the northward migration of the Intertropical Convergence Zone (ITCZ, Nicholson et al, 2018 ). The rainfall pattern is known to have been affected by a pronounced multi-decadal drought episode with unprecedented severity in recorded history between the late 1960s and early 1980s (Losada et al, 2012 ; Nicholson 2018 ; Nicholson et al, 2018 ; Ogou et al, 2019 ).…”

Climate change and primary health care in Chakama, Kilifi County, Kenya

“…In sub-Saharan Africa, the frequency of droughts has increased in the last few decades, and they have become more prolonged. 1 One of the key contributing factors is climate change, leading to reduced rainfall in the region. This in turn has reduced the quantity and quality of water for people.…”