Different responses of the upper ocean to typhoon Namtheun

TL;DR

This study investigates how the upper ocean responds differently to typhoon Namtheun, highlighting the importance of pre-typhoon conditions and subsurface dynamics in shaping surface responses through combined satellite and in situ data.

Contribution

It reveals distinct mechanisms—upwelling and vertical mixing—driving the ocean's response to typhoon Namtheun, emphasizing the need for integrated observations and models.

Findings

Two extreme cooling regions at cyclonic eddy A and wake B.

Different physical responses: upwelling at A, vertical mixing at B.

Pre-typhoon conditions significantly influence ocean responses.

Abstract

The responses of the upper ocean to typhoon Namtheun in July 2004 are investigated by sea surface measurements and vertical profiles. Pre-typhoon ocean environment played an important role in this case. There were two extreme cooling regions located at cyclonic eddy A and typhoon wake B. Although the magnitudes of SST cooling at A and B were similar, other physical and biophysical responses were quite different. Combining multi-satellite data with vertical profile data, it is found that the upwelling dominated the responses at A and the vertical mixing dominated the responses at B. This study implies that to insight into the ocean surface responses to typhoon, the subsurface dynamics need to be analyzed via both the in situ and satellite-based observations, and the physical and biological models.