Comparison and Validation of Long time Serial Global GEOV1 and Regional Australian MODIS Fractional Vegetation Cover Products Over the Australian Continent

Yanling Ding^1,2,Xingming Zheng^1,3,Tao Jiang^1,3,and Kai Zhao^1,3

Abstract: Fractional vegetation cover (FVC) is one of the most critical parameters inmonitoring vegetation status. Comprehensive assessment of the FVC products is critical fortheir improvement and use in land surface models. This study investigates the performancesof two major long time serial FVC products: GEOV1 and Australian MODIS. The spatialand temporal consistencies of these products were compared during the 2000–2012 periodover the main biome types across the Australian continent. Their accuracies were validatedby 443 FVC in-situ measurements during the 2011–2012 period. Our results show that thereare strong correlations between the GEOV1 and Australian MODIS FVC products over themain Australian continent while they exhibit large differences and uncertainties in thecoastal regions covered by dense forests. GEOV1 and Australian MODIS describe similarseasonal variations over the main biome types with differences in magnitude, whileAustralian MODIS exhibit unstable temporal variations over grasslands and shifted seasonalvariations over evergreen broadleaf forests. The GEOV1 and Australian MODIS productsoverestimate FVC values over the biome types with high vegetation density andunderestimate FVC in sparsely vegetated areas and grasslands. Overall, the GEOV1 andAustralian MODIS FVC products agree with in-situ FVC values with a RMSE around 0.10over the Australian continent.

Keywords:FVC products; GEOV1; Australian MODIS; comparison; validation