Extreme austral winter precipitation events over the South-American Altiplano: regional atmospheric features
Extreme austral winter precipitation events over the South-American Altiplano: regional atmospheric features
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南美高原上空的极端南方冬季降水事件：区域大气特征
DOI：
10.1007/s00382-022-06240-1
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发表时间：
2022
期刊：
影响因子：
4.6
通讯作者：
Condom, Thomas
中科院分区：
文献类型：
--
作者：
Segura, Hans;Espinoza, Jhan Carlo;Junquas, Clementine;Lebel, Thierry;Vuille, Mathias;Condom, Thomas
南美洲高原在南方冬季（6月至8月，JJA）有明显的旱季。然而，在这个季节，引发强降水的天气气象条件可能破坏社会经济活动，往往造成人员伤亡。利用北方高原39个雨量站的逐日降水资料，分析了该地区的降水特征。对于JJA季节，我们计算了历史百分位数90（p90），并确定了1980-2010年期间降水量高于p90的极端雨天。我们在该地区确定了100个冬季极端降水事件（WEPE），持续时间为1至16天。对持续1天（42例）、2天（19例）和2天以上（39例）的WEPE的初始日或第0天（0）的ERA中期资料进行了500 hPa高度场的K均值分析。我们发现了59个WEPE的特点是上层槽在秘鲁-智利海岸。在850 hPa，这59个WEPE也与沿沿着东部中部安第斯山脉的冷涌，表明高层槽和冷涌之间的联系在发展中的深对流在北方高原。超前滞后复合分析进一步表明，在这59个WEPE开始前2天，由于源自南美洲赤道上空的低层偏北风异常，亚马逊西部对流层中低层有明显的增湿。其他41个WEPEs与穿越赤道的低层南风和秘鲁-智利海岸上空的中高层低压系统有关。低层南风增强了对流层中层水汽从赤道向高原的输送，这是由于向赤道传播时发展了浅层纬向环流，而低压系统促进了上升运动的加强，增强了从中部安第斯山脉以东低地向高原的上坡水汽输送。
The South American Altiplano has a marked dry season during the austral winter (June to August, JJA). However, during this season synoptic meteorological conditions triggering heavy precipitation can damage socioeconomic activities, often causing the loss of human lives. Using daily in-situ precipitation data from 39 rain-gauge stations over the northern Altiplano (-;m.a.s.l.) for the JJA season, we computed the historical percentile 90 (p90) and we identified extreme rainy days with precipitation higher than p90 in the 1980–2010 period. We identified 100 winter extreme precipitation events (WEPEs) over this region that can last between one to 16 days. The K-means analysis was applied to anomalies of geopotential height at 500 hPa from ERA-Interim data during the initial day or Day(0) of WEPEs lasting 1 day (42 cases), 2 days (19) and more than 2 days (39). We found 59 WEPEs characterized by an upper-level trough over the Peruvian-Chilean coast. At 850 hPa, these 59 WEPEs are also associated with cold surges along the eastern Central Andes, indicating an association between the upper-level trough and the cold surge in developing deep convection over the northern Altiplano. A lead-lag composite analysis further showed a significant lower- and mid-tropospheric moistening over the western Amazon 2 days before the onset of these 59 WEPEs, due to low-level northerly wind anomalies originating over equatorial South America. The other 41 WEPEs are associated with a low-level southerly wind regime crossing the equator and a mid-and upper-level low-pressure system over the Peruvian-Chilean coast. While the low-level southerly regime enhances mid-tropospheric moisture transport from the equator towards the Altiplano due to the developed shallow meridional circulation when propagating equatorward, a low-pressure system promotes intensification of upward motion, boosting the upslope moisture transport from the lowlands to the east of the Central Andes towards the Altiplano.
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DOI：
10.1002/joc.6593
发表时间：
2020-04
期刊：
International Journal of Climatology
影响因子：
--
作者：
Martí Bonshoms;F. Álvarez-García;J. Úbeda;W. Cabos;Kelita Quispe;G. Liguori
通讯作者：
Martí Bonshoms;F. Álvarez-García;J. Úbeda;W. Cabos;Kelita Quispe;G. Liguori
安第斯山脉对截止低点的影响：建模研究*
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
R. Garreaud;H. Fuenzalida
通讯作者：
H. Fuenzalida
用Eta坐标模型模拟南美地区夏季环流
DOI：
--
发表时间：
1995
期刊：
影响因子：
--
作者：
S. Figueroa;P. Satyamurty;P. Dias
通讯作者：
P. Dias
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
C. Vera;Paula K. Vigliarolo
通讯作者：
Paula K. Vigliarolo
关于热带安第斯山脉季节性和年际时间尺度降雨量变化的新见解
影响因子：
4.6
作者：
H. Segura;C. Junquas;J. Espinoza;M. Vuille;Y. R. Jauregui;A. Rabatel;T. Condom;T. Lebel
通讯作者：
T. Lebel