Complementarity of ResourceSat-1 AWiFS and Landsat TM/ETM+ sensors

Abstract

Considerable interest has been given to forming an international collaboration to develop a virtual moderate spatial resolution land observation constellation through aggregation of data sets from comparable national observatories such as the US Landsat, the Indian ResourceSat and related systems. This study explores the complementarity of India's ResourceSat-1 Advanced Wide Field Sensor (AWiFS) with the Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+). The analysis focuses on the comparative radiometry, geometry, and spectral properties of the two sensors. Two applied assessments of these data are also explored to examine the strengths and limitations of these alternate sources of moderate resolution land imagery with specific application domains. There are significant technical differences in these imaging systems including spectral band response, pixel dimensions, swath width, and radiometric resolution which produce differences in observation data sets. None of these differences was found to strongly limit comparable analyses in agricultural and forestry applications. Overall, we found that the AWiFS and Landsat TM/ETM+ imagery are comparable and in some ways complementary, particularly with respect to temporal repeat frequency. We have found that there are limits to our understanding of the AWiFS performance, for example, multi-camera design and stability of radiometric calibration over time, that leave some uncertainty that has been better addressed for Landsat through the Image Assessment System and related cross-sensor calibration studies. Such work still needs to be undertaken for AWiFS and similar observatories that may play roles in the Global Earth Observation System of Systems Land Surface Imaging Constellation.

A Framework for Defining Spatially Explicit Earth Observation Requirements for a Global Agricultural Monitoring Initiative (GEOGLAM)

“…Meanwhile, as demonstrated by Table 1, particularly Requirements #4-6, the use of moderate spatial resolution data collected at a more frequent rate is a priority growth area for analyses spanning the full extent of croplands for fields of all sizes. With the Landsat archive opening, new moderate resolution missions set to launch, and computational resources growing, global scale analyses are poised to move into the moderate resolution domain [59][60][61][62][63][64], with regional to global datasets at 30 m resolution already demonstrated [65][66][67][68][69].…”

Meeting Earth Observation Requirements for Global Agricultural Monitoring: An Evaluation of the Revisit Capabilities of Current and Planned Moderate Resolution Optical Earth Observing Missions

“…At present, ISRO does not provide this data freely to all and their nominal acquisition plan does not include coverage of global agricultural areas. Agencies within the United States-namely, the Department of Agriculture-have procured these data and found them to be valuable for cropland monitoring applications and compatible if not complementary to Landsat data, although some uncertainty about long term radiometric calibration stability remains [6,11,36]. Meanwhile, planned for the near future is the European Space Agency's Sentinel-2 Earth observatory, made up of two separate satellites, each with the Multi-Spectral Instrument (MSI) on-board (S2A, S2B; [37]), the first of which is set for launch in 2015.…”

“…With the Landsat archive opening and computational resources growing, global scale analyses are poised to move into the moderate resolution domain [4][5][6][7][8], with regional to global datasets at 30 m resolution already demonstrated [9][10][11][12][13]. In the context of crop condition monitoring and yield forecasting, moderate resolution data have not yet achieved broad scale results across the globe, primarily due to the lack of consistent cloud free acquisitions with sufficiently high temporal resolution.…”

Expansion of LISS III swath using AWiFS wider swath data and contourlet coefficients learning

“…The differences such as solar illumination angle and satellite viewing C.V. Rao et al angle, which are occurred in the nonoverlapping region with respect to the overlapping region, and RSR differences can be normalized with techniques described in the Table 4 before applying the proposed method to the original data-sets. In Table 4, we described the possibility to correct the bidirectional reflectance distribution function (BRDF) effects in the nonoverlapping region (Walthall et al 1985;Goward et al 2012;Srivastava et al 2014). In our experiments, to avoid the radiometric, BRDF, spectral and geometric differences, we created a simulated AWiFS image by degrading the original LISS III.…”