scholarly journals Seasonal and Inter Annual Variation of Sea Surface Temperature in the Indonesian Waters

2016 ◽  
Vol 30 (2) ◽  
pp. 120
Author(s):  
Martono Martono

Sea surface temperature plays an important role in air-sea interactions. This research was conducted to understand seasonal and interannual variations of sea surface temperature in the Indonesian waters. The data used in this research was daily sea surface temperature in 1986 to 2015 which was obtained from the Physical Oceanography Distributed Active Archive Center - National Aeronautics and Space Administration. Method used in this study was the anomaly analysis. The result showed that the seasonal and interannual variations of sea surface temperature in the Indonesian waters varied. Seasonal variations of SST in the Makasar Strait, Sulawesi Sea, and Halmahera Sea were low. High seasonal variations of sea surface temperature occurred in the southern waters of Java, Timor Sea, Arafura Sea, and Banda Sea, which were allegedly due to the upwelling process. In addition, interannual variation of sea surface temperature in the Indonesian waters fluctuated. From 1986 to 2000, it showed a negative anomaly dominant. Meanwhile, from 2001 to 2015, it showed a positive anomaly dominant. The effect of Indian Ocean Dipole on the fluctuation of sea surface temperature in the Indonesian waters was stronger than ENSO. Within the last 30 years, the sea surface temperature in the Indonesian water indicated a rising trend. The highest sea surface temperature rise occurred in the Halmahera Sea that reached 0.66 OC/30 years and the lowest was in the Timor Sea of 0.36 OC/30 years.

Author(s):  
Michelia Mashita ◽  
Jonson Lumban-Gaol

We analysed the variability of sea surface temperature (SST) and chlorophyll-a concentration (Chl-a) in the eastern Indian Ocean (EIO). We used monthly mean Chl-a and SST data with a 4-km spatial resolution derived from Level-3 Aqua Moderate-resolution Imaging Spectroradiometer (MODIS) distributed by the Asia-Pacific Data-Research Center (APDRC) for the period 2002–2017. Wavelet analysis shows the annual and interannual variability of SST and Chl-a concentration in the EIO. The annual variability of SST and Chl-a is influenced by monsoon systems. During a southeast monsoon, SST falls while Chl-a increases due to upwelling. The annual variability of SST and Chl-a is also influenced by the Indian Ocean Dipole (IOD). During positive phases of the IOD (2006, 2012 and 2015), there was more intense upwelling in the EIO caused by the negative anomaly of SST and the positive anomaly of Chl-a concentration.


2010 ◽  
Vol 23 (13) ◽  
pp. 3699-3719 ◽  
Author(s):  
Shoshiro Minobe ◽  
Masato Miyashita ◽  
Akira Kuwano-Yoshida ◽  
Hiroki Tokinaga ◽  
Shang-Ping Xie

Abstract The atmospheric response to the Gulf Stream front in sea surface temperature is investigated using high-resolution data from satellite observations and operational analysis and forecast. Two types of atmospheric response are observed with different seasonality and spatial distribution. In winter, surface wind convergence is strong over the Gulf Stream proper between Cape Hatteras and the Great Banks, consistent with atmospheric pressure adjustments to sea surface temperature gradients. The surface convergence is accompanied by enhanced precipitation and the frequent occurrence of midlevel clouds. Local evaporation and precipitation are roughly in balance over the Florida Current and the western Gulf Stream proper. In summer, strong precipitation, enhanced high clouds, and increased lightning flash rate are observed over the Florida Current and the western Gulf Stream proper, without seasonal surface convergence enhancement. For the precipitation maximum over the Florida Current, local evaporation supplies about half of the water vapor, and additional moisture is transported from the south on the west flank of the North Atlantic subtropical high. Atmospheric heating estimated by a Japanese reanalysis reveals distinct seasonal variations. In winter, a shallow-heating mode dominates the Gulf Stream proper, with strong sensible heating in the marine atmospheric boundary layer and latent heating in the lower troposphere. In summer, a deep-heating mode is pronounced over the Florida Current and the western Gulf Stream proper, characterized by latent heating in the middle and upper troposphere due to deep convection. Possible occurrences of these heating modes in other regions are discussed.


1995 ◽  
Vol 34 (2) ◽  
pp. 500-510 ◽  
Author(s):  
Randall J. Alliss ◽  
Sethu Raman

Abstract Fields of cloudiness derived from the Geostationary Operational Environmental Satellite VISSR (Visible–Infrared Spin Scan Radiometer) Atmospheric Sounder are analyzed over the Gulf Stream locale (GSL) to investigate seasonal and geographical variations. The GSL in this study is defined as the region bounded from 31° to 38°N and 82° to 66°W. This region covers an area that includes the United States mid-Atlantic coast states, the Gulf Stream, and portions of the Sargasso Sea. Clouds over the GSL are found approximately three-quarters of the time between 1985 and 1993. However, large seasonal variations in the frequency of cloudiness exist. These seasonal variations show a distinct relationship to gradients in sea surface temperature (SST). For example, during winter when large SST gradients are present, large gradients in cloudiness are found. Clouds are observed least often during summer over the ocean portion of the GSL. This minimum coincides with an increase in atmospheric stability due to large-scale subsidence. Cloudiness is also found over the GSL in response to mesoscale convergence areas induced by sea surface temperature gradients. Geographical variations in cloudiness are found to be related to the meteorology of the region. During periods of cold-air advection, which are found most frequently in winter, clouds are found less often between the coastline and the core of the Gulf Stream and more often over the Sargasso Sea. During cyclogenesis, large cloud shields often develop and cover the entire domain. Satellite estimates of cloudiness are found to be least reliable over land at night during the cold months. In these situations, the cloud retrieval algorithm often mistakes clear sky for low clouds. Satellite-derived cloudiness over land is compared with daytime surface observations of cloudiness. Results indicate that retrieved cloudiness agrees well with surface observations. Relative humidity fields taken from global analyses are compared with satellite cloud heights at three levels in the atmosphere. Cloudiness observed at these levels is found at relative humidities in the 75%–100% range but is also observed at humidities as low as 26%.


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