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Two Dead in Crew Attack on board Fishing Vessel .

Two Dead in Crew Attack on board Fishing Vessel .

Somali pirates 'holding 200 crew hostage'.

S. Korean ship attacked by pirates in Indian Ocean.

Piracy off Somalia: First Attack in Seven Months.

Myanmar Mulls New Deep-Sea Port.

Major Tuna Vessel Is Denied Port Landing Because of Evidence of Illegal Fishing.

Somalia: Dozen foreign trawlers arrive Bosaso Port amid concerns of marine exploitation.

S. Korea to make film of Somali piracy raid.

Royal Navy frees Yemeni fishermen from pirates.

Diary of SKorean held by Somali pirates revealed.

S. Korea charges pirates with attempted murder.

MH370: search fleet grows as 'everything thrown at this riddle'.

Why This Narrow Strait Next to Iran Is So Critical to the World's Oil Supply.

The Seychelles-Chagos Thermocline Ridge (SCTR, 5°S-10°S, 50°E-80°E) is a unique open-ocean upwelling region in the southwestern Indian Ocean. Due to the negative wind stress curl between the equatorial westerlies and southeasterly trade winds, SCTR is known as a strong upwelling region with high biological productivity, providing a primary fishing zone for the surrounding countries. Given its importance in shaping the variability of the Indian Ocean climate by understanding the sea-air interaction and its dynamics, the simulation of SCTR is evaluated using outputs from the Coupled Model Intercomparison Project Phase Sixth (CMIP6). Compared to observations, 23 out of 27 CMIP6 models tend to simulate considerably deeper SCTR thermocline depth (defined as the 20°C isotherm depth (D20))- a common bias in climate models. The deep bias is related to the easterly wind bias in the equatorial to southern Indian Ocean, which is prominent in boreal summer and fall. This easterly wind bias produces a weak annual mean Ekman pumping, especially in the boreal fall. Throughout the year, the observed Ekman pumping is positive and is driven by two components: the curl term, is associated with the wind stress curl, leads to upwelling during boreal summer to fall; the beta term, is linked to planetary beta and zonal wind stress, contributes to downwelling during boreal spring to fall. However, the easterly wind bias in the CMIP6 increases both the positive curl and negative beta terms. The beta term bias offsets the curl term bias and reduces the upwelling velocity. Furthermore, the easterly wind bias is likely caused by the reduced east-west sea surface temperature (SST) difference associated with a pronounced warm bias in the western equatorial Indian Ocean, accompanied by the east-west mean sea level pressure gradient over the Indian Ocean. Furthermore, this study finds local wind-induced Ekman pumping to be a more dominant factor in thermocline depth bias than Rossby waves,