Climatology and Interannual Variability of Floods During the TRMM Era (1998-2013)

Spatial and temporal variations of global floods during the TRMM period (1998-2013) are explored by means of the outputs of the Dominant river Routing Integrated with VIC Environment model (DRIVE) driven by the precipitation rates from the TRMM Multi-satellite Precipitation Analysis (TMPA). Climatological and seasonal mean features of floods including frequency (FF), duration (FD), and mean and total intensity (FI and FTI) are examined and further compared to those for a variety of precipitation indices derived from the daily TMPA rain-rates. In general, floods and precipitation manifest similar spatial distributions, confirming that more precipitation (both amount and frequency) often indicates higher probability of floods. However, different flood indices can be associated with different precipitation characteristics with a highly regional-dependent distribution. FF and FD tend to be more related to daily precipitation frequency globally, especially the mid-to-high-end precipitation frequencies (F10, F25, F50). However, FI and FTI tend to be more associated with the mean volume/magnitude of those (extreme) daily precipitation events (Pr10 and Pr25). Nonetheless, daily precipitation intensity except the very high end one (R50) generally has a relatively weak effect on floods. The precipitation-flood relations at the ten large regions are further examined, providing an improved understanding of precipitation-related flood generating mechanisms in different locations. On the interannual time scale, the El Niño-Southern Oscillation (ENSO) can significantly affect floods in many flood-prone zones. However, it is noted that even though the ENSO effect on floods is mostly through modulating various aspects of precipitation events, significant ENSO signals in precipitation can’t always translate to an effective, simultaneous impact on floods.

YAN Yan;  WU Huan;  GU Guojun;  HUANG Zhijun;  ALFIERI Lorenzo;  LI Xiaomeng;  NANDING Nergui;  PAN Xinshun;  TANG Qiuhong; 

2024-08-26

AMER METEOROLOGICAL SOC

JRC119495

0894-8755 (online),   

https://journals.ametsoc.org/view/journals/clim/33/8/jcli-d-19-0415.1.xml,    https://publications.jrc.ec.europa.eu/repository/handle/JRC119495,   

10.1175/JCLI-D-19-0415.1 (online),