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Satellite Microwave Remote Sensing of Landscape Freeze–Thaw Status Related to Frost Hazard Monitoring
Published in George P. Petropoulos, Tanvir Islam, Remote Sensing of Hydrometeorological Hazards, 2017
Youngwook Kim, John S. Kimball, Jinyang Du
Global and regional FT classifications have been generated using a variety of satellite microwave active and passive systems and frequencies as summarized in Table 8.2. Sensor frequencies used for FT retrievals have included L-band (1–2 GHz), C-band (4–8 GHz), X-band (8–12 GHz), Ku-band (12–18 GHz), and Ka-band (27–40 GHz) observations. Satellite FT detection using radiometers has generally low-to-moderate spatial resolutions (>25 km) ranging from shallower characteristic sensing depths at Ka-band to deeper sensing depths at L-band. Similar multifrequency passive microwave radiometer measurements from overlapping sensor records (e.g., Scanning Multichannel Microwave Radiometer [SMMR], Special Sensor Microwave Imager [SSMIS], Advanced Microwave Scanning Radiometer for Earth Observing System [AMSR-E], Advanced Microwave Scanning Radiometer 2 [AMSR2]) operating on polar orbiting operational environmental satellites have enabled the development of long-term (>35years) global data records that can track FT daily, seasonal and interannual variability, and multidecadal trends (Kim et al., 2011, 2012). Satellite Ku-band and C-band scatterometers (e.g., quick scattermeter (QuikSCAT) and advanced scatterometer (ASCAT)) have moderate resolution (~25 km) to retrieve surface FT state, but with greater sensitivity to vegetation and snow cover conditions. Lower frequency (<10 GHz) SAR provides relatively finer resolution (10–100 m), but coarse (on the order of weeks) temporal repeat FT observations. The lower frequency L-band retrievals from SAR and passive microwave radiometers (e.g., SMOS, Soil Moisture Active Passive [SMAP]) also provide potentially enhanced sensitivity to soil FT conditions (Entekhabi et al. 2010).
Global Soil Moisture Estimation Using Microwave Remote Sensing
Published in Ni-Bin Chang, Yang Hong, Multiscale Hydrologic Remote Sensing, 2012
Yang Hong, Sadiq Ibrahim Khan, Chun Liu, Yu Zhang
Examples of spaceborne passive microwave sensors for soil moisture measurements include the Scanning Multichannel Microwave Radiometer (SMMR) on Nimbus-7, the Special Sensor Microwave/Imager (SSM/I) on the Defense Meteorological Satellite Program, the Tropical Rainfall Measuring Mission Microwave (TRMM) imager, the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) on Aqua, the Soil Moisture and Ocean Salinity (SMOS) Mission by the European Space Agency (ESA), and the NASA Soil Moisture Active and Passive (SMAP) Mission.
A Framework for High-Resolution Soil Moisture Extraction Using SCATSAT-1 Scatterometer Data
Published in IETE Technical Review, 2020
Deepak Murugan, Ajay Kumar Maurya, Akanksha Garg, Dharmendra Singh
Soil moisture (SM) is an important variable that has a major role in energy and water exchanges at land surface/atmosphere interface and in water resource management. It can be used for weather and climate prediction, drought indication, crop monitoring, soil erosion, flood control, etc. Therefore, it is necessary to develop a satellite-based system/algorithm for estimating the soil moisture at regional and global levels. Passive microwave remote sensing has been widely used to estimate soil moisture globally [1] and some of the passive sensors include Scanning Multichannel Microwave Radiometer (SMMR), Advanced Microwave Scanning Radiometer (AMSR-E), WindSat, and Soil Moisture and Ocean Salinity (SMOS). Soil moisture retrieval using active remote sensing has also been extensively researched. SM retrieval for regional scales using synthetic aperture radar (SAR) data, such as phased array L band synthetic aperture radar (PALSAR), PALSAR-2, RADARSAT-2 and Sentinel-1, is carried out [2–6] and for global scales scatterometer data are used, such as ASCAT, ERS 1 and QuickSCAT [7,8]. Soil Moisture Active Passive (SMAP) satellite launched with combination of scatterometer and radiometer for global soil moisture retrieval. But due to failure of the scatterometer, it currently works as a radiometer and is actively used to retrieve global soil moisture.