Use of Remote Sensing Observations to Study the Urban Climate on Tropical Coastal Cities

Abstract

Local climate change effects due to urban growth have been characterized by great continental cities. This research is focused in the study of similar local climate effects due to urbanization in tropical coastal cities. With the use of remote sensing technology, climate changes due to urban growth can be detected. Airborne sensors can provide high resolution images that can be analyzed to identify the different components of the surface energy budget. The clearest local indicator of climate changes due to urban growth is an urban/rural convective circulation known as Urban Heat Islands (UHI). The main scientific objective of this research is to investigate the impact of the fast urbanization in the local climate of tropical coastal cities that is related to UHI. A field campaign was designed and executed in February 2004 to validate this phenomenon. The field campaign included measurements with on-board high resolution infrared (IR) sensors, ground weather stations, and upper air radiosonde balloons. The experimental campaign was denominated San Juan ATLAS Mission. The Airborne Thermal and Land Applications Sensor (ATLAS) from NASA/Stennis that operates in the visual and IR bands was used as the main sensor for this field campaign with the objective of investigating the Urban Heat Island (UHI) in San Juan, Puerto Rico. Temperatures as high as 60 °C over the developed areas differ from temperatures over vegetated areas of more than 30 °C during daytime. Results from this research have shown outstanding evidence of elevated surface temperatures over the urban landscape and clearly validate the development of UHI in San Juan, Puerto Rico.