Relating fish kills to upwellings and wind patterns in the Salton Sea
In recent years, the extreme eutrophication of the Salton Sea has been associated with massive fish kills and associated bird kills. Analysis of the magnitude and direction of high wind events indicates that major fish kills are preceded by strong and persistent wind events, with a 24-h accumulated wind magnitude above a critical threshold of approximately 90 m/s. Twelve of the 14 cases of reported fish kills analyzed were found to be preceded by such wind conditions. The winds could potentially produce upwellings of hypolimnetic water at the upwind end of the Sea, resulting in the entire water column being low in dissolved oxygen and high in concentrations of hydrogen sulfide and ammonium. Remotely sensed thermal infrared data from the MODIS instrument on the Terra satellite was available for 5 of the 14 fish kills analyzed. Evaluation of satellite-derived surface temperature maps for these 5 fish kills shows that upwellings did take place after the wind events, affecting a large fraction of the Sea’s area. The location of the upwelling and the fish kills coincided in all cases, confirming the relationship among wind patterns, upwellings, and fish kills in the Salton Sea. The importance of physically mediated processes, such as upwellings, need to be considered in evaluating future remediation strategies for the Salton Sea.
KeywordsInfrared Remote sensing MODIS
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- Brown, O. B. & P. J. Minnett, 1999. MODIS Infrared Sea Surface Temperature Algorithm: Algorithm Theoretical Basis Document, Version 2.0. University of Miani, NAS5-31361.Google Scholar
- Hook, S. J., F. J. Prata, R. E. Alley, A. Abtahi, R. C. Richards, S. G. Schladow & S. O. Palmarsson, 2003. Retrieval of lake bulk and skin temperatures using along-track scanning radiometer (ATSR-2) data: a case study using Lake Tahoe, California. Journal of Atmospheric and Oceanic Technology 20: 534–548.CrossRefGoogle Scholar
- Hook, S. J., R. G. Vaughan, H. Tonooka & S. G. Schladow, 2007. Absolute radiometric in-flight validation of mid infrared and thermal infrared data from ASTER and MODIS on the Terra spacecraft using the Lake Tahoe, CA/NV, USA, automated validation site. IEEE Transactions Geoscience and Remote Sensing 45: 1798–1807.CrossRefGoogle Scholar
- MacIntyre, S., 1998. Turbulent mixing and resource supply to phytoplankton. In Imberger, J. (ed.), Physical Processes in Lakes and Oceans. American Geophysical Union, Washington DC: 561–590.Google Scholar
- Mitch, W. J. & J. G. Gosselink, 2000. Wetlands. Van Nostrand Reinhold, New York.Google Scholar
- Patten, M. A., G. McCaskie & P. Unitt, 2003. Birds of the Salton Sea. Status, Biogeography, and Ecology. University of California Press, Berkeley, California.Google Scholar
- Preisendorfer, R. W., 1988. Principal Component Analysis in Meteorology and Oceanography. Elsevier, New York.Google Scholar
- Shuford, W. D., N. Warnock, K. C. Molina & K. K. Sturm, 2002. The Salton Sea as critical habitat to migratory and resident waterbirds. In Barnum, D. A., J. F. Elder, D. Stephens & M. Friend (eds), The Salton Sea. Hydrobiologia 473: 255–274.Google Scholar