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characterize geographic differences in the seasonality and year-to-year variability of river flow. The river discharge sites were selected to be “reasonably free from human-induced discontinuities.” Results from this analysis implied that seasonality in river discharge rates varies regionally, depending on the timing of maximum precipitation (PREC), potential evapotranspiration (PET), and snowmelt. For example, river discharge rates in eastern and southern South America, the southwestern United States
characterize geographic differences in the seasonality and year-to-year variability of river flow. The river discharge sites were selected to be “reasonably free from human-induced discontinuities.” Results from this analysis implied that seasonality in river discharge rates varies regionally, depending on the timing of maximum precipitation (PREC), potential evapotranspiration (PET), and snowmelt. For example, river discharge rates in eastern and southern South America, the southwestern United States
more difficult to determine. Long-term (e.g., decadal) remote sensing analyses of canopy greenness and energy absorption are becoming routine ( Goetz et al., 2000 ; Hicke et al., 2002a ; Lobell et al., 2002 ; Myneni et al., 1997 ; Tucker et al., 2001 ), but large-scale, high-resolution data have not been available to evaluate remotely sensed measures. Hicke et al. ( Hicke et al., 2002a ) proposed that the large increase in NPP during the 1980s and 1990s in the central United States was likely
more difficult to determine. Long-term (e.g., decadal) remote sensing analyses of canopy greenness and energy absorption are becoming routine ( Goetz et al., 2000 ; Hicke et al., 2002a ; Lobell et al., 2002 ; Myneni et al., 1997 ; Tucker et al., 2001 ), but large-scale, high-resolution data have not been available to evaluate remotely sensed measures. Hicke et al. ( Hicke et al., 2002a ) proposed that the large increase in NPP during the 1980s and 1990s in the central United States was likely
1. Introduction The impact of water pollution from diffuse sources on surface waters has been of increasing concern during the past several decades. Nonpoint source (NPS) water pollution is the leading cause of water quality impairment [(Environmental Protection Agency) EPA, 2000 ; Novotny, 1999 ]. NPS pollutants are mainly transported by storm runoff to surface water bodies. Studies have been undertaken to trace these pollutants back to their sources, to understand transport mechanisms, and
1. Introduction The impact of water pollution from diffuse sources on surface waters has been of increasing concern during the past several decades. Nonpoint source (NPS) water pollution is the leading cause of water quality impairment [(Environmental Protection Agency) EPA, 2000 ; Novotny, 1999 ]. NPS pollutants are mainly transported by storm runoff to surface water bodies. Studies have been undertaken to trace these pollutants back to their sources, to understand transport mechanisms, and
