Remote Sensing Application in Water Resources Planning

Remote sensing-based satellite data and processing tools as part of geographic information system (GIS) have been utilized in many disciplines in earth sciences, water resources management in particular. Retrieving spatial data and processing technology require a systematic knowledge and experience for an effective use that is the main motivation of this chapter. Field work in large areas and installing gauges have been painstaking and costly. Even the developed countries began to remove gauges measuring eddy-covariance and other meteorological variables due to the high maintaining cost. Instead, they invest on satellite technologies and radar systems. Today, most field works and conventional point data collection have given its place to processing synoptic satellite images using open source GIS tools. The use of spectral indicators and remote sensing technologies to control and monitor the water quality and quantity of rivers, reservoirs and groundwater has been very cost-effective. Different variables that can be remotely measured in water quality are salinity, suspended sediment, water color, extent of oil spill and eutrophication, growing phytoplankton and algal bloom. Also, estimation of land cover and land use, actual evapotranspiration, land surface temperature, runoff, preparation of flood maps, determination of snow cover and depth changes may benefit from remote sensing-based satellite data and GIS technology. To do operations in physical sciences, basic knowledge in remote sensing and geographic information systems (GIS) is necessary as they depend each other. First, basic data is collected and then processed by sensors of remote sensing satellites using different color spectra or recorded thermal properties. This leads to the creation of raw databases that are processed in GIS to enhance data and utilize information management and store layer composition. Modeling, production of output maps and spatial analysis are very fast and accurate with GIS tools such as gdal, pyproj, pymodis libraries in Python language and 3D data storage in common data format (netCDF). GIS is a very powerful management tool for planners and designers to adopt appropriate land and water management strategies. Since remote sensing and GIS are deep and extensive source, studying the principles and methods require a structured summary of basics and relevant applications in the field of water management and engineering.