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Social and Behavioral Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Geography

Remote sensing

2003

Articles 1 - 3 of 3

Full-Text Articles in Social and Behavioral Sciences

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu Jan 2003

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu

OES Faculty Publications

[1] New evidence based on recent satellite data is presented to provide a rare opportunity in quantifying the long-speculated contribution of tropical cyclones to enhance ocean primary production. In July 2000, moderate cyclone Kai-Tak passed over the South China Sea (SCS). During its short 3-day stay, Kai-Tak triggered an average 30-fold increase in surface chlorophyll-a concentration. The estimated carbon fixation resulting from this event alone is 0.8 Mt, or 2-4% of SCS's annual new production. Given an average of 14 cyclones passing over the SCS annually, we suggest the long-neglected contribution of tropical cyclones to SCS's annual new production may …


Measuring The Physical Composition Of Urban Morphology Using Multiple Endmember Spectral Mixture Models, Tarek Rashed, John R. Weeks, Dar Roberts, John Rogan, Rebecca Powell Jan 2003

Measuring The Physical Composition Of Urban Morphology Using Multiple Endmember Spectral Mixture Models, Tarek Rashed, John R. Weeks, Dar Roberts, John Rogan, Rebecca Powell

Geography

The application of multiple endmember spectral mixture analysis (MESMA) to map the physical composition of urban morphology using Landsat Thematic Mapper (TM) data is evaluated and tested. MESMA models mixed pixels as linear combinations of pure spectra, called endmembers, while allowing the types and number of endmembers to vary on a per-pixel basis. A total of 63 two-, three-, and four-endmember models were applied to a Landsat TM image for Los Angeles County, and a smaller subset of these models was chosen based on fraction and root-mean-squared error (RMSE) criteria. From this subset, an optimal model was selected for each …


Land-Cover Change Monitoring With Classification Trees Using Landsat Tm And Ancillary Data, John Rogan, Jennifer Miller, Doug Stow, Janet Franklin, Lisa Levien, Chris Fischer Jan 2003

Land-Cover Change Monitoring With Classification Trees Using Landsat Tm And Ancillary Data, John Rogan, Jennifer Miller, Doug Stow, Janet Franklin, Lisa Levien, Chris Fischer

Geography

We monitored land-cover change in San Diego County (1990-1996) using multitemporal Landsat TM data. Change vectors of Kauth Thomas features were combined with stable multitemporal Kauth Thomas features and a suite of ancillary variables within a classification tree classifier. A combination of aerial photointerpretation and field measurements yielded training and validation data. Maps of land-cover change were generated for three hierarchical levels of change classification of increasing detail: change vs. no-change; four classes representing broad increase and decrease classes; and nine classes distinguishing increases or decreases in tree canopy cover, shrub cover, and urban change. The multitemporal Kauth Thomas (both …