ENSO Related Seasonal Range Prediction over South America

Proceedings

Lupo, Anthony R.¹ 

关键词: seasonal forecasting;    South Pacific;    teleconnections;    South America;    ENSO;    blocking;    precipitation;   

DOI  :  10.3390/ecas2017-04140

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

Seasonal range prediction over North America has been based on intraseasonal and interannual variability related to the Pacific North America (PNA) pattern and El Niño and Southern Oscillation (ENSO), respectively. These phenomena have an impact on the occurrence of atmospheric blocking and the long-term conditions for North America. Similar relationships may be found for seasonal range prediction over South America. Previous studies have examined ENSO-related variability of the South Pacific Jetstream as well as atmospheric blocking. Using the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalyses, the character of the monthly circulations were studied over the South Pacific/South America sector from 2000–2016. Initial results show that there is a negative correlation in the upper air circulation over the East Pacific and South America during winter for ENSO. Also, the interannual variability in the jet-stream pattern for the region as related to ENSO shows a 180° phase difference. Finally, there is evidence that the circulation pattern for the 2000–2016 may be different from that of the latter part of the 20th century as indicated by a recent reversal of the interdecadal variability of atmospheric blocking over the South Pacific Region.

【 授权许可】

CC BY