Open Ocean Impacts on Thai Costal Ecosystem in Andaman Sea
Weidong Yu, Somkiat Khokiattiwong, Yanliang Liu, Liang Xue First Institute of Oceanography, SOA, China Phuket Marine Biological Center, MNRE, Thailand
Acknowledgement to: Kuiping Li, Huiwu Wang, Varintha Vasinamekhin, Sirisuk Petchamnan, Sontaya Sosanuy, Nuttida Chanthasiri, Komsun Thongtaem, Jenwit Thammavichan, Isaman Madsit Unique Andaman Sea: (1) monsoon rainfall center Unique Andaman Sea: (2) big rivers
Mean Sea Surface Salinity New Technology and Observation: Changing Our View
Bay of Bengal and Andaman Sea: one of the freshest oceans on earth
Unique Andaman Sea: (3) Oxygen Minimum Zone Unique Andaman Sea: (4) Strong Internal waves
The island chain acts as the source of the internal wave, triggered by the tide-topography interaction.
Unique Andaman Sea: (5) Exposure to equatorial Kelvin wave forcing
Equatorial Kelvin wave +Coastal Trapped Kelvin wave
CTKW
MJO
Kelvin Wave CTKW
Wyrtki Jet Eastern pole of IOD Indonesian Java Upwelling Throughflow
Tuna spawning area shallow deep shallow deep
温跃层变化（m）
Thermocline evolution (semi-annual variations) deep Downwelling Kelvin wave
shallow Upwelling Kelvin wave
Downwelling deep Kelvin wave
Upwelling shallow Kelvin wave
90 100 110 120 130 经度 距离/×0 . 25°
Along the equator Along the eastern coast of Thermocline depth of the Andaman Sea eastern coast of Andaman Sea
The semi-annual variations of the thermocline along eastern coastal Andaman Sea in response to the TIO forcing (equatorial Kelvin waves + coastal Kelvin waves) Andaman Sea is the ideal region for multidisciplinary study
Oxygen Minimum Zone (OMZ)
Upper boundary ～ 100m Deep Ocean Shallow continental shelf ～ ～ 3000m 100m
Internal waves Thermocline propagating eastward ～ 100-130m
Connected to tropical Indian Ocean through Kelvin waves
Under seasonal forcing (monsoon) Under inter-annual forcing (IOD/ENSO) Hypothesis: In case of thermocline shoaling, the internal waves bring the cold and low oxygen water onto the continental shelf.
Internal Sea Intrusion and wave surface breaking on shelf
Low Low oxygen thermocline oxygen water water
Deep thermocline case Shallow thermocline case
Concept Model
Oxygen Minimum Zone (OMZ)
Upper boundary ～ 100m Deep Ocean Shallow continental shelf ～ ～ 3000m 100m
Internal waves Thermocline propagating eastward ～ 100-130m
Eddies
Connected to tropical Indian Ocean through Kelvin waves
Under seasonal forcing (monsoon) Under interannual forcing (IOD/ENSO) Monitoring Line Deep Ocean – Continental Shelf Interaction ---- multidisciplinary survey
VPR, UCTD/CTD, buoy/moorings, Nets, Samples Thanks Let’s work together