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Estimation of land surface temperature-vegetation abundance relationship for urban heat island studies / Q. Wenger in Remote sensing of environment, vol 89 n° 4 (29/02/2004)
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Titre : Estimation of land surface temperature-vegetation abundance relationship for urban heat island studies Type de document : Article/Communication Auteurs : Q. Wenger, Auteur ; Dong Lu, Auteur ; J. Schubring, Auteur Année de publication : 2004 Article en page(s) : pp 467 - 483 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] classification
[Termes IGN] exitance spectrale
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] température de surface
[Termes IGN] texture d'image
[Termes IGN] Thematic Mapper
[Termes IGN] traitement d'image
[Termes IGN] zone urbaineRésumé : (Auteur) Remote sensing of urban heat islands (UHls) has traditionally used the Normalized Difference Vegetation Index (NDVI) as the indicator of vegetation abundance to estimate the land surface temperature (LST)-vegetation relationship. This study investigates the applicability of vegetation fraction derived from a spectral mixture model as an alternative indicator of vegetation abundance. This is based on examination of a Landsat Enhanced Thematic Mapper Plus (ETM+) image of Indianapolis City, IN, USA, acquired on June 22, 2002. The transformed ETM+ image was unmixed into three fraction images (green vegetation, dry soil, and shade) with a constrained least-square solution. These fraction images were then used for land cover classification based on a hybrid classification procedure that combined maximum likelihood and decision tree algorithms. Results demonstrate that LST possessed a slightly stronger negative correlation with the unmixed vegetation fraction than with NDVI for all land cover types across the spatial resolution (30 to 960 m). Correlations reached their strongest at the 120-m resolution, which is believed to be the operational scale of LST, NDVI, and vegetation fraction images. Fractal analysis of image texture shows that the complexity of these images increased initially with pixel aggregation and peaked around 120 m, but decreased with farther aggregation. The spatial variability of texture in LST was positively correlated with those in NDVI and in vegetation fraction. The interplay between thermal and vegetation dynamics in the context of different land cover types leads to the variations in spectral radiance and texture in LST. These variations are also present in the other imagery, and are responsible for the spatial patterns of urban heat islands. It is suggested that the areal measure of vegetation abundance by unmixed vegetation fraction has a more direct correspondence with the radiative, thermal, and moisture properties of the Earth's surface that determine LST. Numéro de notice : A2004-072 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.11.005 En ligne : https://doi.org/10.1016/j.rse.2003.11.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26600
in Remote sensing of environment > vol 89 n° 4 (29/02/2004) . - pp 467 - 483[article]Impact of imagery temporal on land-cover change detection monitoring / R.S. Lunetta in Remote sensing of environment, vol 89 n° 4 (29/02/2004)
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Titre : Impact of imagery temporal on land-cover change detection monitoring Type de document : Article/Communication Auteurs : R.S. Lunetta, Auteur ; D.M. Johnson, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 444 - 454 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] acquisition d'images
[Termes IGN] analyse diachronique
[Termes IGN] Caroline du Nord (Etats-Unis)
[Termes IGN] détection de changement
[Termes IGN] écosystème
[Termes IGN] flore locale
[Termes IGN] forêt
[Termes IGN] image Landsat-TM
[Termes IGN] luminance lumineuse
[Termes IGN] occupation du sol
[Termes IGN] surveillance forestièreRésumé : (Auteur) An important consideration for monitoring land-cover (LC) change is the nominal temporal frequency of remote sensor data acquisitions required to adequately characterize change events. Ecosystem-specific regeneration rates are an important consideration for determining the required frequency of data collections to minimize change omission errors. Clear-cut forested areas in north central North Carolina undergo rapid colonization from pioneer (replacement) vegetation that is often difficult to differentiate spectrally from that previously present. This study compared change detection results for temporal frequencies corresponding to 3-, 7-, and 10-year time intervals for near-anniversary date Landsat 5 Thematic Mapper (TM) data acquisitions corresponding to a single path/row. Change detection was performed using an identical change vector analysis (CYA) technique for all imagery dates. Although the accuracy of the 3-year analysis was acceptable (86.3%, K = 0.55), a significant level of change omission errors resulted (51.7%). Accuracies associated with both the 7-year (43.6%, K = 0. 10) and 10year (37.2%, K= 0.05) temporal frequency analyses performed poorly, with excessive change omission errors of 84.8% and 86.3%, respectively. The average rate of LC change observed over the study area for the 13-year index period (1987-2000) was approximately 1.0% per annum. Overall results indicated that a minimum of 3-4-year temporal data acquisition frequency is required to monitor LC change events in north central North Carolina. Reductions in change omission errors could probably best be achieved by further increasing temporal data acquisition frequencies to a 1-2-year time interval. Numéro de notice : A2004-071 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.10.022 En ligne : https://doi.org/10.1016/j.rse.2003.10.022 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26599
in Remote sensing of environment > vol 89 n° 4 (29/02/2004) . - pp 444 - 454[article]Effect of grain size on remotely sensed spectral reflectance of sandy desert surfaces / G.S. Okin in Remote sensing of environment, vol 89 n° 3 (15/02/2004)
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Titre : Effect of grain size on remotely sensed spectral reflectance of sandy desert surfaces Type de document : Article/Communication Auteurs : G.S. Okin, Auteur ; T.H. Painter, Auteur Année de publication : 2004 Article en page(s) : pp 272 - 280 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] désert
[Termes IGN] érosion éolienne
[Termes IGN] image AVIRIS
[Termes IGN] réflectance
[Termes IGN] sable
[Termes IGN] transfert radiatifRésumé : (Auteur) The effect of soil surface texture on spectral reflectance is reported for a site in the Mojave Desert. Abandoned central-pivot agricultural fields in the Manix Basin of southeastern California have introduced deflationary surface, into the otherwise stable, armored desert surface. This has resulted in sand plumes, eroded from the fields by wind, transported by saltation and deposited downwind of the fields. Grain size analysis of this wind-transported material reveals a fractionation by size within the plume, with smaller effective particle size toward the toe of the plume. This fractionation results from the greater mobility of smaller particles, and the longer saltation paths they take once airborne. Radiative transfer modeling of quartz grains with absorbing rinds indicates that the difference in grain size observed in the field should be revealed in apparent surface reflectance and are resolvable within the noise-equivalent delta-reflectance of the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) instrument. Analysis of AVIRIS-derived apparent surface reflectance demonstrates the expected negative correlation between effective grain size of sand in the plume and reflectance, with the most significant correlations in the short-wave infrared. The change in reflectance per mm change in particle diameter was - 0.06 at & ~ 1.7 um and - 0.08 at & ~ 2.2 um with R2 = 0.89 and 0.93, respectively. Numéro de notice : A2004-018 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.10.008 En ligne : https://doi.org/10.1016/j.rse.2003.10.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26546
in Remote sensing of environment > vol 89 n° 3 (15/02/2004) . - pp 272 - 280[article]Estimating fractional snow cover from MODIS using the normalized difference snow index / V.V. Salomonson in Remote sensing of environment, vol 89 n° 3 (15/02/2004)
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Titre : Estimating fractional snow cover from MODIS using the normalized difference snow index Type de document : Article/Communication Auteurs : V.V. Salomonson, Auteur ; I. Appel, Auteur Année de publication : 2004 Article en page(s) : pp 351 - 360 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande infrarouge
[Termes IGN] bande visible
[Termes IGN] image Terra-MODIS
[Termes IGN] manteau neigeux
[Termes IGN] méthode robuste
[Termes IGN] neige
[Termes IGN] Normalized Difference Snow Index
[Termes IGN] réalité de terrainRésumé : (Auteur) Snow-cover information is important for a wide variety of scientific studies, water supply and management applications. The NASA Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) provides improved capabilities to observe snow cover orn space and has been successfully using a normalized difference snow index (NDSI), along with threshold tests, to provide global, automated binary maps of snow cover. The NDSI is a spectral band ratio that takes advantage of the spectral differences of snow in short-wave infrared and visible MODIS spectral bands to identify snow versus other features in a scene. This study has evaluated whether there is a "signal" in the NDSI that could be used to estimate the fraction of snow within a 500 in MODIS pixel and thereby enhance the use of the NDSI approach in monitoring snow cover. Using Landsat 30-m observations as "ground truth," the percentage of snow cover was calculated for 500-m cells. Then a regression relationship between 500-m NDSI observations and fractional snow cover was developed over three different snow-covered regions and tested over other areas. The overall results indicate that the relationship between fractional snow cover and NDSI is reasonably robust when applied locally and over large areas like North America. The relationship offers advantages relative to other published fractional snow cover algorithms developed for global-scale use with MODIS. This study indicates that the fraction of snow cover within a MODIS pixel using this approach can be provided with a mean absolute error less than 0.1 over the range from 0.0 to 1.0 in fractional snow cover. Numéro de notice : A2004-019 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.10.016 En ligne : https://doi.org/10.1016/j.rse.2003.10.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26547
in Remote sensing of environment > vol 89 n° 3 (15/02/2004) . - pp 351 - 360[article]Predicting in situ pasture quality in the Kruger National Park, South Africa, using continuum-removed absorption features / Onisimo Mutanga in Remote sensing of environment, vol 89 n° 3 (15/02/2004)
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Titre : Predicting in situ pasture quality in the Kruger National Park, South Africa, using continuum-removed absorption features Type de document : Article/Communication Auteurs : Onisimo Mutanga, Auteur ; Andrew K. Skidmore, Auteur ; Herbert H.T. Prins, Auteur Année de publication : 2004 Article en page(s) : pp 393 - 408 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Afrique du sud (état)
[Termes IGN] azote
[Termes IGN] biochimie
[Termes IGN] carbone
[Termes IGN] forêt tropicale
[Termes IGN] image hyperspectrale
[Termes IGN] parc naturel national
[Termes IGN] paturage
[Termes IGN] phosphore
[Termes IGN] potassium
[Termes IGN] prairie
[Termes IGN] réflectance végétale
[Termes IGN] régression linéaire
[Termes IGN] savane
[Termes IGN] spectroradiomètre
[Termes IGN] zone intertropicaleRésumé : (Auteur) The remote sensing of pasture quality as determined by nitrogen, phosphorous, potassium, calcium and magnesium concentration is critical for a better understanding of wildlife and livestock feeding patterns. Although remote sensing techniques have proved useful for assessing the concentration of foliar biochemicals under controlled laboratory conditions, more investigation is required to assess their capabilities in the field where inconsistent results have been obtained so far. We investigated the possibility of determining the concentration of in situ biochemicals in a savanna rangeland, using the spectral reflectance of five grass species. Canopy spectral measurements were taken in the field using a GER 3700 spectroradiometer. We tested the utility of using four variables derived from continuum-removed absorption features for predicting canopy nitrogen, phosphorous, potassium, calcium and magnesium concentration: (i) continuum-removed derivative reflectance (CRDR), (ii) band depth (BD), (iii) band depth ratio (BDR) and (iv) normalised band depth index (NBDI). Stepwise linear regression was used to select wavelengths from the absorption-feature-based variables. Univariate correlation analysis was also done between the first derivative reflectance and biochemicals. Using a training data set, the variables derived from continuum-removed absorption features could predict biochemicals with R2 values ranging from 0.43 to 0.80. Results were highest using CRDR data, which yielded R2 values of 0.70, 0.80, 0.64, 0.50 and 0.68 with root mean square errors (RMSE) of 0.01, 0.004, 0.03, 0.01 and 0.004 for nitrogen, phosphorous, potassium, calcium and magnesium, respectively. Predicting biochemicals on a test data set, using regression models developed from a training data set. resulted in R2 values ranging from 0. 15 to 0.70. The error of prediction (RSE) in the test data set was 0.08 (+ 10.25% of mean), 0.05 (+ 5.2% of mean), 0.02 (+ 11.11% of mean), 0.05 (+ 11.6% of mean) and 0.03 (+ 15% of mean) for nitrogen, potassium, phosphorous. calcium and magnesium, respectively, using CRDR. When data was partitioned into species groups, the R2 increased significantly to >0.80. With high-quality radiometric and geometric calibration of hyperspectral imagery, the techniques applied in this study (i.e. continuum removal on absorption features) may also be applied on data acquired by airborne and spacebome imaging spectrometers to predict and ultimateIy to map the concentration of macronutrients in tropical rangelands. Numéro de notice : A2004-020 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.11.001 En ligne : https://doi.org/10.1016/j.rse.2003.11.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26548
in Remote sensing of environment > vol 89 n° 3 (15/02/2004) . - pp 393 - 408[article]Mapping the aerodynamic roughness length of desert surfaces from the POLDER/ADEOS bi-directional reflectance product / Béatrice Marticorena in International Journal of Remote Sensing IJRS, vol 25 n° 3 (February 2004)
PermalinkAn autonomous above-water system for the validation of ocean color radiance data / G. Ziborni in IEEE Transactions on geoscience and remote sensing, vol 42 n° 2 (February 2004)
PermalinkPhenomenological analysis of simulated signals observed over shaded areas in an urban scene / Christophe Miesch in IEEE Transactions on geoscience and remote sensing, vol 42 n° 2 (February 2004)
PermalinkSystematic corrections of AVHRR image composites for temporal studies / J. Cihlar in Remote sensing of environment, vol 89 n° 2 (30/01/2004)
PermalinkNarrowband-to-broadband albedo conversion for glacier ice and snow: equations based on modeling and ranges of validity of the equations / W. Greuell in Remote sensing of environment, vol 89 n° 1 (15/01/2004)
PermalinkToward universal broad leaf chlorophyll indices using PROSPECT simulated database and hyperspectral reflectance measurements / G. Le Maire in Remote sensing of environment, vol 89 n° 1 (15/01/2004)
PermalinkHyperspectral monitoring of physiological parameters of wheat during a vegetation period using AVIS data / N. Oppelt in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)
PermalinkSpectral characteristics and feature selection of hyperspectral remote sensing data / X. Jiang in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)
PermalinkThe EuroSTARRS airborne campaign in support of the SMOS mission: first results over land surfaces / K. Saleh in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)
PermalinkVegetation/SPOT: an operational mission for the Earth monitoring, presentation of new standard product / P. Maisongrande in International Journal of Remote Sensing IJRS, vol 25 n° 1 (January 2004)
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