Hawaiian Regional Climate Variability during Two Types of El Niño

• DOI: 10.1175/jcli-d-19-0985.1
• Publication Date: 2020-08-31T18:11:59Z
• Authors: Bo-Yi Lu; Pao-Shin Chu; Sung-Hun Kim; Christina Karampe...
• Keywords: Jet stream; Forcing (mathematics); Subtropical ridge; Hadley cell; Walker circulation; Atmospheric Circulation

Abstract The large-scale atmospheric circulation of the North Pacific associated with two types El Niño—the eastern (EP) and central (CP)—is studied in relation to Hawaiian winter (December–February) rainfall temperature. equatorial undergo active convective heating during EP Niño winters. local Hadley is enhanced an upper-level westerly jet stream elongated eastward. Due impact both phenomena, stronger anomalous descending motion, moisture flux divergence anomalies near Hawaii, reduction easterly trade winds, which are characteristic winters, unfavorable for Hawaii. As a result this robust signal, dry conditions prevail Hawaii standard deviation winters smaller than climatology. For CP maximum ocean warming weaker shifted westward date line. subtropical retreats relative anomalously sinking motion variable generally weaker. Although still exists over Pacific, its magnitude Without strong external forcing, Islands close long-term mean. spread from one event another also larger. near-surface minimum temperature three stations reveals cooling slight