TY  - JOUR
A1  - Ozturk, Ugur
A1  - Malik, Nishant
A1  - Cheung, Kevin
A1  - Marwan, Norbert
A1  - Kurths, Jürgen
T1  - A network-based comparative study of extreme tropical and frontal storm rainfall over Japan
JF  - Climate dynamics : observational, theoretical and computational research on the climate system
N2  - Frequent and intense rainfall events demand innovative techniques to better predict the extreme rainfall dynamics. This task requires essentially the assessment of the basic types of atmospheric processes that trigger extreme rainfall, and then to examine the differences between those processes, which may help to identify key patterns to improve predictive algorithms. We employ tools from network theory to compare the spatial features of extreme rainfall over the Japanese archipelago and surrounding areas caused by two atmospheric processes: the Baiu front, which occurs mainly in June and July (JJ), and the tropical storms from August to November (ASON). We infer from complex networks of satellite-derived rainfall data, which are based on the nonlinear correlation measure of event synchronization. We compare the spatial scales involved in both systems and identify different regions which receive rainfall due to the large spatial scale of the Baiu and tropical storm systems. We observed that the spatial scales involved in the Baiu driven rainfall extremes, including the synoptic processes behind the frontal development, are larger than tropical storms, which even have long tracks during extratropical transitions. We further delineate regions of coherent rainfall during the two seasons based on network communities, identifying the horizontal (east-west) rainfall bands during JJ over the Japanese archipelago, while during ASON these bands align with the island arc of Japan.
KW  - Extreme rainfall
KW  - Baiu
KW  - Tropical storms
KW  - Event synchronization
KW  - Complex networks
Y1  - 2019
U6  - https://doi.org/10.1007/s00382-018-4597-1
SN  - 0930-7575
SN  - 1432-0894
VL  - 53
IS  - 1-2
SP  - 521
EP  - 532
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Boers, Niklas
A1  - Bookhagen, Bodo
A1  - Marwan, Norbert
A1  - Kurths, Jürgen
T1  - Spatiotemporal characteristics and synchronization of extreme rainfall in South America with focus on the Andes Mountain range
JF  - Climate dynamics : observational, theoretical and computational research on the climate system
N2  - 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.
KW  - Extreme rainfall
KW  - Synchronization
KW  - Complex networks
KW  - South American monsoon system
Y1  - 2016
U6  - https://doi.org/10.1007/s00382-015-2601-6
SN  - 0930-7575
SN  - 1432-0894
VL  - 46
SP  - 601
EP  - 617
PB  - Springer
CY  - New York
ER  -