Relation between seasonally detrended shortwave infrared reflectance data and land surface moisture in semi-arid Sahel
Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Standard
Relation between seasonally detrended shortwave infrared reflectance data and land surface moisture in semi-arid Sahel. / Olsen, Jørgen Lundegaard; Ceccato, Pietro; Proud, Simon Richard; Fensholt, Rasmus; Grippa, Manuela; Mougin, Eric; Ardö, Jonas; Sandholt, Inge.
I: Remote Sensing, Bind 5, Nr. 6, 2013, s. 2898-2927.Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Relation between seasonally detrended shortwave infrared reflectance data and land surface moisture in semi-arid Sahel
AU - Olsen, Jørgen Lundegaard
AU - Ceccato, Pietro
AU - Proud, Simon Richard
AU - Fensholt, Rasmus
AU - Grippa, Manuela
AU - Mougin, Eric
AU - Ardö, Jonas
AU - Sandholt, Inge
PY - 2013
Y1 - 2013
N2 - In the Sudano-Sahelian areas of Africa droughts can have serious impacts on natural resources, and therefore land surface moisture is an important factor. Insufficient conventional sites for monitoring land surface moisture make the use of Earth Observation data for this purpose a key issue. In this study we explored the potential of using reflectance data in the Red, Near Infrared (NIR), and Shortwave Infrared (SWIR) spectral regions for detecting short term variations in land surface moisture in the Sahel, by analyzing data from three test sites and observations from the geostationary Meteosat Second Generation (MSG) satellite. We focused on responses in surface reflectance to soil- and surface moisture for bare soil and early to mid- growing season. A method for implementing detrended time series of the Shortwave Infrared Water Stress Index (SIWSI) is examined for detecting variations in vegetation moisture status, and is compared to detrended time series of the Normalized Difference Vegetation Index (NDVI). It was found that when plant available water is low, the SIWSI anomalies increase over time, while the NDVI anomalies decrease over time, but less systematically. Therefore SIWSI may carry important complementary information to NDVI in terms of vegetation water status, and can provide this information with the unique combination of temporal and spatial resolution from optical geostationary observations over Sahel. However, the relation between SIWSI anomalies and periods of water stress were not found to be sufficiently robust to be used for water stress detection.
AB - In the Sudano-Sahelian areas of Africa droughts can have serious impacts on natural resources, and therefore land surface moisture is an important factor. Insufficient conventional sites for monitoring land surface moisture make the use of Earth Observation data for this purpose a key issue. In this study we explored the potential of using reflectance data in the Red, Near Infrared (NIR), and Shortwave Infrared (SWIR) spectral regions for detecting short term variations in land surface moisture in the Sahel, by analyzing data from three test sites and observations from the geostationary Meteosat Second Generation (MSG) satellite. We focused on responses in surface reflectance to soil- and surface moisture for bare soil and early to mid- growing season. A method for implementing detrended time series of the Shortwave Infrared Water Stress Index (SIWSI) is examined for detecting variations in vegetation moisture status, and is compared to detrended time series of the Normalized Difference Vegetation Index (NDVI). It was found that when plant available water is low, the SIWSI anomalies increase over time, while the NDVI anomalies decrease over time, but less systematically. Therefore SIWSI may carry important complementary information to NDVI in terms of vegetation water status, and can provide this information with the unique combination of temporal and spatial resolution from optical geostationary observations over Sahel. However, the relation between SIWSI anomalies and periods of water stress were not found to be sufficiently robust to be used for water stress detection.
U2 - 10.3390/rs5062898
DO - 10.3390/rs5062898
M3 - Journal article
AN - SCOPUS:84880433754
VL - 5
SP - 2898
EP - 2927
JO - Remote Sensing
JF - Remote Sensing
SN - 2072-4292
IS - 6
ER -
ID: 104677158