Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - FraRI
T2 - an algorithm to account for the discontinuity at 60 degrees N in MODIS temperature products
AU - Sedda, Luigi
AU - Morley, David W.
AU - Benz, David
AU - Wint, G. R. William
AU - Wan, Zhengming
AU - Rogers, David J.
PY - 2013
Y1 - 2013
N2 - The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites conducts continuous monitoring of the Earth's land surface and oceans. Recently, a sharp discontinuity (averaging 1.9 degrees C) has been noticed at 60 degrees N in both MODIS daytime and night-time land surface temperature (LST) products. This linear artefact arises because the CO2 high cloud test in the operational code for the generation of the MODIS cloud mask product is used only in the non-polar region (between 60 degrees N and 60 degrees S). The resulting discontinuity clearly has negative implications for any statistical applications of these temperature data. In this technical note we present a new algorithm, which minimizes this discontinuity. The method uses edge detection and elimination based on a mixture of Sobel and non-linear Laplacian filters (edge detection and quantification), cubic splines (edge modelling), and a controllable power function for image restoration. The implementation of this algorithm is demonstrated on an image of average minimum night-time LST between 2001 and 2008.
AB - The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites conducts continuous monitoring of the Earth's land surface and oceans. Recently, a sharp discontinuity (averaging 1.9 degrees C) has been noticed at 60 degrees N in both MODIS daytime and night-time land surface temperature (LST) products. This linear artefact arises because the CO2 high cloud test in the operational code for the generation of the MODIS cloud mask product is used only in the non-polar region (between 60 degrees N and 60 degrees S). The resulting discontinuity clearly has negative implications for any statistical applications of these temperature data. In this technical note we present a new algorithm, which minimizes this discontinuity. The method uses edge detection and elimination based on a mixture of Sobel and non-linear Laplacian filters (edge detection and quantification), cubic splines (edge modelling), and a controllable power function for image restoration. The implementation of this algorithm is demonstrated on an image of average minimum night-time LST between 2001 and 2008.
KW - CLOUD DETECTION
KW - EDGE-DETECTION
KW - VALIDATION
KW - IMAGES
U2 - 10.1080/01431161.2012.718467
DO - 10.1080/01431161.2012.718467
M3 - Journal article
VL - 34
SP - 1220
EP - 1233
JO - International Journal of Remote Sensing
JF - International Journal of Remote Sensing
SN - 0143-1161
IS - 4
ER -