113
6
Spatiotemporal
Interactions among
Soil Moisture,
Vegetation Cover, and
Evapotranspiration in
the Tampa Bay Urban
Region, Florida
Ni-Bin Chang and Zhemin Xuan
6.1 INTRODUCTION
More than half of the world population live in cities (Population Reference Bureau
2007). Many cities in dry land environments, such as Las Vegas and Phoenix in the
southwest United States, are increasingly faced with water problems due to their
rapidly growing populations. Approximately 2.8 billion people have suffered from
weather-related disasters since 1967, with droughts comprising 60% and floods
CONTENTS
6.1 Introduction .................................................................................................. 113
6.2 Materials and Methods ................................................................................. 115
6.2.1 Estimation of Enhanced Vegetation Index ....................................... 115
6.2.2 Estimation of Soil Moisture .............................................................. 116
6.2.2.1 Remote Sensing Image Collection ..................................... 116
6.2.2.2 Urban Environment and Ground-Truth Data Collection ... 117
6.2.2.3 Derivation of Soil Moisture from MODIS Data ................ 119
6.2.3 Estimation of Evapotranspiration ..................................................... 119
6.3 Results and Discussion ................................................................................. 120
6.3.1 Generation of Soil Moisture Maps ................................................... 120
6.3.2 Retrieval of Spatiotemporal Ecohydrologic Patterns ....................... 126
6.4 Conclusions ................................................................................................... 134
References .............................................................................................................. 135
6
Spatiotemporal
Interactions among
Soil Moisture,
Vegetation Cover, and
Evapotranspiration in
the Tampa Bay Urban
Region, Florida
Ni-Bin Chang and Zhemin Xuan
6.1 INTRODUCTION
More than half of the world population live in cities (Population Reference Bureau
2007). Many cities in dry land environments, such as Las Vegas and Phoenix in the
southwest United States, are increasingly faced with water problems due to their
rapidly growing populations. Approximately 2.8 billion people have suffered from
weather-related disasters since 1967, with droughts comprising 60% and floods
CONTENTS
6.1 Introduction .................................................................................................. 113
6.2 Materials and Methods ................................................................................. 115
6.2.1 Estimation of Enhanced Vegetation Index ....................................... 115
6.2.2 Estimation of Soil Moisture .............................................................. 116
6.2.2.1 Remote Sensing Image Collection ..................................... 116
6.2.2.2 Urban Environment and Ground-Truth Data Collection ... 117
6.2.2.3 Derivation of Soil Moisture from MODIS Data ................ 119
6.2.3 Estimation of Evapotranspiration ..................................................... 119
6.3 Results and Discussion ................................................................................. 120
6.3.1 Generation of Soil Moisture Maps ................................................... 120
6.3.2 Retrieval of Spatiotemporal Ecohydrologic Patterns ....................... 126
6.4 Conclusions ................................................................................................... 134
References .............................................................................................................. 135