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

• Published in: Atmospheric and Oceanic Science Letters
• Main Authors: Faustin Katchele OGOU, Qing YANG, Yawen DUAN, Zhuguo MA
• Format: Article in Journal/Newspaper
• Language: English
• Published: KeAi Communications Co., Ltd. 2019
• Subjects: Decadal variability; moving average filter; empirical orthogonal function; cumulative sum chart; sub-Saharan Africa; central North China; Environmental sciences; GE1-350; Oceanography; GC1-1581; Pacific; North Atlantic; North Atlantic oscillation
• Online Access: https://doi.org/10.1080/16742834.2019.1593040; https://doaj.org/article/ecab0d9c6a8247b7ab4d499b795acfb2

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.