Spatiotemporal characteristics and synchronization of extreme rainfall in South America with focus on the Andes Mountain range

Author(s)

Boers, Niklas ^{[1, 2]} ; Bookhagen, Bodo ^[3] ; Marwan, Norbert ^[2] ; Kurths, Juergen ^{[4, 5, 1, 2]}

Affiliation

^[1] Humboldt Univ, Dept Phys, Invalidenstr 110, Berlin - Germany

^[2] Potsdam Inst Climate Impact Res, Telegraphenberg A 31, D-14473 Potsdam, Brandenburg - Germany

^[3] Univ Potsdam, Inst Earth & Environm Sci, Brandenburg - Germany

^[4] Nizhnii Novgorod State Univ, Dept Control Theory, Nizhnii Novgorod - Russia

^[5] Univ Aberdeen, Inst Complex Syst & Math Biol, Aberdeen - Scotland

• Document type: Journal article
• Source: Climate Dynamics; v. 46, n. 1-2, p. 601-617, JAN 2016.
• Web of Science Citations: 17

Abstract

The South American Andes are frequently exposed to intense rainfall events with varying moisture sources and precipitation-forming processes. In this study, we assess the spatiotemporal characteristics and geographical origins of rainfall over the South American continent. Using high-spatiotemporal resolution satellite data (TRMM 3B42 V7), we define four different types of rainfall events based on their (1) high magnitude, (2) long temporal extent, (3) large spatial extent, and (4) high magnitude, long temporal and large spatial extent combined. In a first step, we analyze the spatiotemporal characteristics of these events over the entire South American continent and integrate their impact for the main Andean hydrologic catchments. Our results indicate that events of type 1 make the overall highest contributions to total seasonal rainfall (up to 50%). However, each consecutive episode of the infrequent events of type 4 still accounts for up to 20% of total seasonal rainfall in the subtropical Argentinean plains. In a second step, we employ complex network theory to unravel possibly non-linear and long-ranged climatic linkages for these four event types on the high-elevation Altiplano-Puna Plateau as well as in the main river catchments along the foothills of the Andes. Our results suggest that one to two particularly large squall lines per season, originating from northern Brazil, indirectly trigger large, long-lasting thunderstorms on the Altiplano Plateau. In general, we observe that extreme rainfall in the catchments north of approximately 20 degrees S typically originates from the Amazon Basin, while extreme rainfall at the eastern Andean foothills south of 20 degrees S and the Puna Plateau originates from southeastern South America. (AU)

• FAPESP's process: 11/50151-0 - Dynamical phenomena in complex networks: fundamentals and applications
• Grantee: Elbert Einstein Nehrer Macau
• Support Opportunities: Research Projects - Thematic Grants