Increasing trends for the surface heat flux and fresh water flux in the North Pacific eastern subtropical region

• Published in: Geophysical research letters Vol. 38; no. 10
• Main Authors: Iwasaki, Shinsuke, Kubota, Masahisa
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01.05.2011; American Geophysical Union; John Wiley & Sons, Inc
• Subjects: Atmospheric sciences; Circulation; Earth sciences; Earth, ocean, space; Exact sciences and technology; Flux; Fresh water; Heat; Heat flux; Humidity; Latent heat; Marine; Meteorology; Sea surface temperature; surface fresh water flux; surface heat flux; trend; Trends; Pacific Ocean; Northeast Pacific; North Pacific; satellites; trend-surface analysis; Space remote sensing; Wind velocity; Satellite observation; Specific humidity; air; Sea surface temperature; Hadley cell; subtropical zone; atmospheric circulation; heat flux; fresh water; heat transfer; Atmospheric humidity; latent heat
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2011GL047128

We investigated trends for surface net heat flux (NET) and fresh water flux (FWF) over the eastern subtropical region in the North Pacific for the period of 1988–2005 using satellite‐based data set. It is concluded that NET and FWF remarkably increased during this period. Latent heat flux (LHF) mainly contributes to the increase in NET. Moreover, in order to clarify which flux has larger contribution to the increase in LHF, we investigated four LHF products. Both of the increase in the wind speed (U) and the decrease in the air specific humidity (Qa) have critical contribution to the increase in LHF. In contrast, the decrease of the sea surface temperature (SST) which contributes the decrease in LHF is also found. Also, we proposed a possible mechanism that the increase in U and the decrease in Qa are induced by the strengthened descending branch of local Hadley circulation, associated with change of SST around this region. Key Points The air specific humidity is necessary in increasing of latent heat flux The decrease in air specific humidity is induced by local Hadly circulation The atmosphere circulation is associated with change of sea surface temperature