This study compares terrain-corrected polarimetric variables derived from L-band ALOS-2 PALSAR-2 acquired over a forested and mountainous region of southeast British Columbia (BC) during a drier and a wetter date. Backscatter, polarimetric decomposition parameters, and polarimetric discriminators were compared across 5 broad fuel types (forest, sparse, unforested, incomplete burn, complete burn) to examine if values differ between fuel moisture conditions as characterized by the value of the Drought Code (DC). Polarimetric variables suitable for use in fuel moisture modeling were identified using a one-way analysis of variance (ANOVA) test of significance applied to the normalized differences of these variables between 2 images. Values of linearly polarized backscatter, circularly polarized backscatter, and the parameters of the Van Zyl decomposition had relatively large normalized differences between 2 distinct DC values. The values of parameters of the Cloude-Pottier and Neumann decompositions did not differ between distinct DC values. Relatively large normalized differences occurred with polarimetric discriminators including the total power, maximum and minimum of scattering intensity, the maximum of power received, the maximum and minimum of the completely polarized component, and the maximum of the completely unpolarized component. Results differed by fuel type. Cette & eacute;tude compare les variables polarim & eacute;triques corrig & eacute;es du relief, d & eacute;riv & eacute;es des donn & eacute;es en bande L des capteurs ALOS-2 PALSAR-2 acquises au-dessus d'une r & eacute;gion foresti & egrave;re et montagneuse du sud-est de la Colombie-Britannique au Canada lors d'une p & eacute;riode s & egrave;che et d'une p & eacute;riode humide. La r & eacute;trodiffusion, les param & egrave;tres de d & eacute;composition polarim & eacute;trique et les discriminateurs polarim & eacute;triques ont & eacute;t & eacute; compar & eacute;s pour cinq grands types de combustibles (for & ecirc;t, clairsem & eacute;, non bois & eacute;, br & ucirc;lis incomplet, br & ucirc;lis complet) afin d'examiner si les valeurs diff & egrave;rent selon l'humidit & eacute; du combustible, caract & eacute;ris & eacute;e par la valeur de l'indice de s & eacute;cheresse (IS). Les variables polarim & eacute;triques pertinentes pour la mod & eacute;lisation de l'humidit & eacute; du combustible ont & eacute;t & eacute; identifi & eacute;es par une analyse de variance (ANOVA) & agrave; un facteur appliqu & eacute; aux diff & eacute;rences normalis & eacute;es de ces variables entre les deux images. Les valeurs de la r & eacute;trodiffusion polaris & eacute;e lin & eacute;airement, de la r & eacute;trodiffusion polaris & eacute;e circulairement et les param & egrave;tres de la d & eacute;composition de Van Zyl pr & eacute;sentaient des diff & eacute;rences normalis & eacute;es relativement importantes entre les deux niveaux distincts d'IS. Les valeurs des param & egrave;tres des d & eacute;compositions de Cloude-Pottier et de Neumann ne diff & eacute;raient pas entre les valeurs d'IS. Des diff & eacute;rences normalis & eacute;es relativement importantes ont & eacute;t & eacute; observ & eacute;es avec les discriminateurs polarim & eacute;triques, notamment la puissance totale, les valeurs maximales et minimales de l'intensit & eacute; de diffusion, la puissance maximale re & ccedil;ue, le maximum et minimum de la composante totalement polaris & eacute;e et le maximum de la composante totalement non polaris & eacute;e. Les r & eacute;sultats variaient selon le type de combustible.
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