An Arctic‐Tibetan Connection on Subseasonal to Seasonal Time Scale. Issue 5 (6th March 2019)

• Record Type: Journal Article
• Authors: Zhang, Yang; Zou, Tao; Xue, Yongkang
• Is Part Of: Geophysical research letters. Volume 46:Issue 5(2019)
• Page Start: 2790
• Page End: 2799
• Publication Date: 2019-03-06
• Subjects: subseasonal to seasonal prediction -- land surface temperature -- Tibetan snow anomaly -- Arctic‐Tibetan wave train; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2018GL081476
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Recent research indicates the great potentials of springtime land surface temperature (LST) as a new source of predictability to improve the subseasonal to seasonal climate prediction. In this study, we explore the initial cause of the springtime large‐scale LST in Tibetan Plateau (TP) and disentangle its close connection with the February wave activities from the Arctic region. Our Maximum Covariance Analysis show that the spring LST in TP is significantly coupled with the regional snow cover in the preceding months. The latter is further strongly coupled with the February atmospheric circulation and wave activities in mid‐to‐high latitudes. When the atmospheric circulation is in a combined pattern of Arctic Oscillation and West Pacific teleconnection pattern, wave trains from the Arctic can propagate and reach the TP through northern and southern pathways. This brings dynamical and moisture conditions for the TP snowfall and builds a bridge for Arctic‐Tibetan connection. Plain Language Summary: Subseasonal to seasonal prediction, especially the prediction of extreme events as droughts and floods, is one of the major challenges of climate predictions. Recent research suggests the great potentials of springtime land surface temperature (LST) as a new source of predictability to improve subseasonal to seasonal prediction. This study explores the initial cause of the springtime LST anomaly in Tibetan Plateau (TP), through which its close connection with the wintertime wave activities from the Arctic region is discovered. We find that the wave trains from the Arctic can propagate and reach the TP through northern and southern paths, which favors the snowfall in Tibet. The resultant snow anomaly in late winter further affects the springtime LST in TP, which is suggested to be a predictor for the droughts and floods events in Asian monsoon region in early summer. Given the strong influence of TP on the climate variability and water resources in Asian region, our new finding further implies the much broader and long‐lasting impacts of Arctic changes on the Asian climate and ecosystem, which has not been comprehensively explored and deserves future studies. Key Points: Spring surface air temperature in Tibetan Plateau is found significantly linked to the February atmospheric circulation via snow anomaly When general circulation is in a combined AO+ and WP‐ pattern in February, wave trains from Arctic propagate via north and south paths reaching Tibet The resultant snow anomaly affects spring surface temperature in Tibetan Plateau, suggesting an Arctic‐Tibetan connection on S2S time scale