Modulation of Interannual SST by the Seasonal Cycle in the Tropical Indian Ocean: A Study of Physical Processes

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

4215 Climate And Interannual Variability (3309), 4227 Diurnal, Seasonal, And Annual Cycles, 4231 Equatorial Oceanography, 4500 Oceanography: Physical, 4504 Air/Sea Interactions (0312)

Scientific paper

Modulation of sea surface temperature (SST) patterns by interactions between seasonal and interannual variabilities in the Indian Ocean (IO) region are studied via a hierarchy of experiments utilizing both a 4-1/2 layer ocean model in a realistic tropical Indian Ocean basin, and a version of this same ocean model coupled to a model of the atmospheric mixed layer (AML). Results demonstrate that seasonal atmospheric forcing enhances positive (negative) SSTa in the western (eastern) IO basin associated with both the 1994 and 1997 Indian Ocean Zonal Mode (IOZM) events, ˜ 1oC respective to a control run. Additionally, when seasonal forcing is removed from the system, the 1994 cool event in the eastern basin is prolonged by about 2 months. This indicates the seasonal cycle of atmospheric forcing is at least partly responsible for the timely termination of IOZM events at the end of an event year. To determine the specific physical processes leading to interannual IO SSTa modulation by seasonal variability, the coupled ocean-AML model is used to examine the effects on SSTa of each of the following in isolation: (1) thermocline variability and horizontal advection forced by seasonal wind stress variability; (2) vertical mixing due to seasonal wind speed; (3) changes in surface heat flux due to seasonal wind speed; and (4) variation in radiative forcing via seasonal cloud variability. Of these processes, those driven by seasonal wind stress variability prove most significant to IOZM amplification by the seasonal cycle, and to the timing of event termination. An analysis of the thermodynamics associated with seasonal wind stress forcing is presented, in which the relative contributions of each process represented in the model mixed layer temperature equation are compared, for both a control run and a run in which seasonal variability is removed from the wind stress forcing.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Modulation of Interannual SST by the Seasonal Cycle in the Tropical Indian Ocean: A Study of Physical Processes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Modulation of Interannual SST by the Seasonal Cycle in the Tropical Indian Ocean: A Study of Physical Processes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modulation of Interannual SST by the Seasonal Cycle in the Tropical Indian Ocean: A Study of Physical Processes will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1178250

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.