An investigation into the role of synoptic conditions on Central African precipitation variability

• Autorzy: Zebaze, Sinclaire , Pathak, Raju , Komkoua Mbienda, A. J. , Pokam Mba, Wilfried , Salunke, Popat , Anand, Abhishek , Vondou, Derbetini Appolinaire , Lenouo, André , Mishra, Saroj Kanta
• Języki publikacji: EN

Abstrakty

EN

The synoptic precipitation variability over Central Africa (CA) in the March-to-May (MAM) and September-to-November (SON) seasons is investigated in this study. The composite analysis is used to highlight the evolution of synoptic precipitation, related convection, and dynamic fields. Composite analysis findings show that synoptic precipitation anomalies increase/ fade with an increase/decrease in convection, with the largest amplitude over 5° S–10° N and 2.5–20° E in MAM and 5° N–7.5° N and 5–15° E in SON. Precipitation anomalies and convection associated with the synoptic variability progress eastward preceded (followed) by eastward (westward) low-level wind. This synoptic sequence is associated with a downward motion and an inflow, indicating the storm’s presence, which contributes significantly to precipitation initiation over CA. The empirical orthogonal function for precipitation during the SON season is lower than that observed during the MAM season in the context of the size and spatial pattern. During these precipitation occurrences, the zonal moisture component contributes the most to the moisture initiation over the region. The findings of this study show that the observed convergence/ divergence position remains unchanged in intensity irrespective of the positive/negative precipitation events. Overall, the synoptic-scale conditions in MAM contribute around 58% of the total variability in precipitation.

Słowa kluczowe

PL

Afryka Centralna; opad atmosferyczny; analiza kompozytowa; zmienność synoptyczna

EN

Central Africa; precipitation; composite analysis; synoptic variability

• Czasopismo: Acta Geophysica
• Rocznik: 2022
• Tom: Vol. 70, no 2
• Strony: 943--962
• Opis fizyczny: Bibliogr. 61 poz.

Twórcy

autor

Zebaze, Sinclaire

• Department of Physics Faculty of Science, University of Yaounde I, P.O. BOX 812, Yaounde, Cameroon,

autor

Pathak, Raju

• Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, India
• Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia

autor

Komkoua Mbienda, A. J.

• Department of Physics Faculty of Science, University of Yaounde I, P.O. BOX 812, Yaounde, Cameroon
• Department of Physics, Faculty of Science, University of Dschang, Dschang, Cameroon
• Earth System Physics Section, Abdus Salam ICTP, Trieste, Italy

autor

Pokam Mba, Wilfried

• Department of Physics Faculty of Science, University of Yaounde I, P.O. BOX 812, Yaounde, Cameroon
• Higher Teacher Training College, University of Yaounde I, Yaounde, Cameroon

autor

Salunke, Popat

• Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, India

autor

Anand, Abhishek

• Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, India

autor

Vondou, Derbetini Appolinaire

• Department of Physics Faculty of Science, University of Yaounde I, P.O. BOX 812, Yaounde, Cameroon

autor

Lenouo, André

• Department of Physics, Faculty of Science, University of Douala, Douala, Cameroon

autor

Mishra, Saroj Kanta

• Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, India

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Uwagi

PL

Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023).

Identyfikatory

DOI

10.1007/s11600-022-00754-2