TY - JOUR
T1 - Seasonal precipitation in south-central Chile
T2 - Trends in extreme events since 1900
AU - González-Reyes, Álvaro
AU - Jacques-Coper, Martín
AU - Muñoz, Ariel A.
N1 - Publisher Copyright:
© 2021. Universidad Nacional Autónoma de México, Centro de Ciencias de la Atmósfera. This is an open access article under the CC BY-NC License (http://creativecommons.org/licenses/by-nc/4.0/).
PY - 2021
Y1 - 2021
N2 - We study a regional precipitation time series built upon seven meteorological records from south-central Chile (SCC; 37°–42° S), which altogether cover the period 1900–2019. As a first objective, we investigated changes in the return period (RP) of dry (< P20) and wet (> P80) seasonal extreme events of precipitation (SEE) for each season. We observed a reduction in the RP of wet SEE during 1900–1950 in all seasons. Moreover, the dry SEE RP shows a reduction from 1950 to the present in all seasons. This phenomenon is noteworthy since 1900 for summer and winter, and since 1930 for autumn. Spring registers a constant RP value from 1990 onwards. As a second objective, we study possible relationships between seasonal precipitation variability and climate modes, such as the Southern Annular Mode (SAM) and the Tripole Index (TPI) of sea surface temperature (SST) over the Pacific Ocean. Summer and autumn precipitation showed a significant negative correlation with SAM activity at interannual and decadal scales, while winter and spring precipitation recorded a significant positive correlation with SST variability over multiple regions of the Pacific Ocean (including the tropics and New Zealand) and the Southern Ocean (Amundsen-Bellingshausen Sea). Finally, we confirm that SAM strongly modulates precipitation in SCC, especially in autumn, and that SEE variability in SCC is considerably associated with climate modes of tropical and extra-tropical origin.
AB - We study a regional precipitation time series built upon seven meteorological records from south-central Chile (SCC; 37°–42° S), which altogether cover the period 1900–2019. As a first objective, we investigated changes in the return period (RP) of dry (< P20) and wet (> P80) seasonal extreme events of precipitation (SEE) for each season. We observed a reduction in the RP of wet SEE during 1900–1950 in all seasons. Moreover, the dry SEE RP shows a reduction from 1950 to the present in all seasons. This phenomenon is noteworthy since 1900 for summer and winter, and since 1930 for autumn. Spring registers a constant RP value from 1990 onwards. As a second objective, we study possible relationships between seasonal precipitation variability and climate modes, such as the Southern Annular Mode (SAM) and the Tripole Index (TPI) of sea surface temperature (SST) over the Pacific Ocean. Summer and autumn precipitation showed a significant negative correlation with SAM activity at interannual and decadal scales, while winter and spring precipitation recorded a significant positive correlation with SST variability over multiple regions of the Pacific Ocean (including the tropics and New Zealand) and the Southern Ocean (Amundsen-Bellingshausen Sea). Finally, we confirm that SAM strongly modulates precipitation in SCC, especially in autumn, and that SEE variability in SCC is considerably associated with climate modes of tropical and extra-tropical origin.
KW - Tripole Index of sea surface temperature of the Pacific Ocean (TPI)
KW - extreme seasonal precipitation events
KW - south-central Chile
KW - southern annular mode (SAM)
UR - http://www.scopus.com/inward/record.url?scp=85100760245&partnerID=8YFLogxK
U2 - 10.20937/ATM.52871
DO - 10.20937/ATM.52871
M3 - Article
AN - SCOPUS:85100760245
SN - 0187-6236
VL - 34
SP - 371
EP - 384
JO - Atmosfera
JF - Atmosfera
IS - 4
ER -