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AGU Poster Material. Karl Rittger Draft. Poster will have 2 sections. Land surface properties using the MODIS satellites for Energy Balance Reconstruction Model Land surface temperature (Aqua and Terra) Net longwave equations fSCA , fVEG, fROCK, Albedo (Terra)
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AGU Poster Material Karl Rittger Draft
Poster will have 2 sections • Land surface properties using the MODIS satellites for Energy Balance Reconstruction Model • Land surface temperature (Aqua and Terra) • Net longwave equations • fSCA, fVEG, fROCK, Albedo (Terra) • fSCA: reconstruction model/potential melt equation • Albedo: Net shortwave Equation • fVEG: longwave and shortwave attenuation equations that include canopy attenuation • Albedo • Net shortwave equations • Within and between basin topographic distribution of SWE • Basin Characteristics • Elevation • Streamflow • Precipitation • Vegetation • Within Basin variability
Energy Balance of the Snowpackduring melt Loss of latent heat of fusion Due to meltwater leaving The snowpack Net Allwave Sensible and Latent Rainfall sensible and latent Ground heat conduction: Negligible Improve outgoing longwave: Land Surface Temperature LST Improve outgoing shortwave: Albedo α Improve melt flux: Fractional Snow Cover fSCA
Improving Estimates of Melt Flux Snow Covered Area Snow Covered Area Snow Cover Depletion, Upper San Joaquin Correct SCA for Viewable Gap Fraction using National Landcover Dataset
Net Shortwave Albedo, α Observed (not calculated)
Net Longwave Incoming Thermal Radiation from atmosphere Incoming thermal radiation from surrounding terrain Idso formulation (Idso, 1981) Watchman Correction (Hodges et al, 1983)
Effects of Vegetation on Shortwave and Longwave Canopy Density Incoming Shortwave: Nonlinear isolation transmission coefficient multiplied by incident solar radiation National Land Cover Data (NLCD) Land Cover Incoming Longwave: Weighted emissivity on basis of proportion forest cover Cline, D.W., Carroll, T.R., 1999, US Army Corp of Engineers, 1956
Sierra Basin Topography/Vegetation • Box-whiskers plot of elevation • Box-whiskers plot of forest fraction • Box-whiskers plot of shrub fraction • Box-whiskers plot of barren fraction
Sierra Wide • μ and σ of SWE with date/elevation • This shows elevations where the most snow is stored in the Sierra Nevada • μ and σ of SWE with date/latitude • This show the latitude where the most snow is stored in the Sierra Nevada
Within Basin SWE distribution • μ and σ of SWE with date/elevation (within) • Show 5 representative basins 8 years • Times/elevations with largest std deviation need to be measured more frequently • Note: Highest elevations aren’t accurately represented • what about the distribution on April 1?
Between Basin SWE distribution • μ and σ of SWE with date/elevation (within)
Extra Ideas • Repeat with Vegetation corrected SWE • Use knowledge of subpixel land cover to constrain SCA/vegetation changes