URBAN HOT ISLAND PHENOMENON OF SAN ANTONIO TEXAS USING TIME SERIES OF TEMPERATURE FROM MODIS IMAGES

Urban Hot Islands have been forming over a period of time in the United States and around the world. The urban hot island phenomenon occurs when the air in the urban city is 2-8°F hotter than the surrounding rural area. Scientific data has shown that the month of July’s maximum temperature during the last 30 to 80 years has been steadily increasing at a rate of one-half to one degree Fahrenheit every ten years. Each city’s urban hot island varies based on the city structure and thus the variance in the range of temperatures within the island. The expected results of this project using MODIS Imagery was to show that the downtown area of San Antonio will have a higher temperature than the rural area as a result from the absorption and storage of solar energy by the urban environment and the heat released into the atmosphere from industrial and communal processes. The MODIS/Aqua (EOS PM) (MOD 11-Land Surface Temperature & Emissivity) satellites orbit around the earth and pass south to north over the equator at 2:00 pm in the afternoon. MODIS Imagery is playing a vital role in the development of interactive Earth system models able to predict global change accurately. MODIS/Aqua can view the entire earth’s surface every 1 to 2 days, acquiring data in 36 spectral bands, or groups of wavelengths. Results from this data acquisition showed that July 13th had the hottest average day temperature of 118.4°F and July 10th had the hottest average night temperature of 85.2°F for the month of July 2004. The following dates: July 4th day, July 13th day, July 16th night, and July 19th night images showed the hottest temperatures to be mostly in the downtown center of San Antonio. All the other images from day and night for July 2004 showed different areas that were hotter than the downtown center. This data will improve our understanding of global dynamics and the processes occurring on the land and in the lower atmosphere.