Effects of Temperature and Precipitation Changes on a Small Watershed in the Northeastern U.S.Sleepers River WatershedClimate of Sleepers RiverSlide 4Slide 5Experiment designExperimentSlide 8Slide 9Slide 10Slide 11Conclusions - Temperature change scenarioSlide 13Slide 14Slide 15Conclusions - Precipitation change scenarioEffects of Temperature and Precipitation Changes on a Small Watershed in the Northeastern U.S.Jon GoodallNathan JohnsonCynthia LancasterAmy NeuenschwanderGil StrassbergSleepers River Watershed•Vermont – USGS cold area historical data base•Covers 111.25 km2•Land cover is 67% Forest and 33% AgricultureClimate of Sleepers RiverPrecipitation: 1,100 mm/yr (25% snow)Snow cover is continuous November through AprilSleepers River050100150200250300111212345678910111212345678910111212345678910111212345678910111212345678910(blank)1969 1970 1971 1972 1973 1974 (blank)mm/m2/monthSum of Precipitation1yearMonth Average monthly precipitationClimate of Sleepers River050100150200250300111212345678910111212345678910111212345678910111212345678910111212345678910(blank)1969 1970 1971 1972 1973 1974 (blank)W/m2Average of downward shortwave radiationyearMonth 050100150200250300350400111212345678910111212345678910111212345678910111212345678910111212345678910(blank)1969 1970 1971 1972 1973 1974 (blank)W/m2Average of downward longwave radiationyearMonth Average Monthly Downward Shortwave Radiation Average Monthly Downward long wave RadiationClimate of Sleepers RiverAverage monthly air temperatures250260270280290300111212345678910111212345678910111212345678910111212345678910111212345678910(blank)1969 1970 1971 1972 1973 1974 (blank)kAverage of TempyearMonth Average monthly specific humiditySpecific humidity correlates well with temperature - expectedExperiment designTwo experiments with changing the forcing data:1. Increasing and decreasing T by 2o2. Increasing and decreasing precipitation by a factor of 2Global warmingChange in precipitation patternsExperiment•Increased evapotranspiration (both transpiration and soil evaporation)•Decreased soil moisture•Increased sensible heat•Changes in patterns of snow depth and snowmelt (i.e. lesser snow depths and earlier snowmelt)Scenario 1: Temperature change scenarioHypothesis:Observed data:•Soil evaporation•Transpiration•Total evapotranspiration•Sensible heat flux•Snow depth•SnowmeltExperimentScenario 1: Temperature change scenarioCanopy evaporation was smallExperimentSoil Moisturefor Temperature Scenarios0501001502002503003501 2 3 4 5 6 7 8 9 10 11 12MonthSoil Moisture[mm]COLDORIGINALHOTScenario 1: Temperature change scenarioExperimentScenario 1: Temperature change scenarioExperimentScenario 1: Temperature change scenarioConclusions - Temperature change scenario•Evapotranspiration (soil evaporation and transpiration) is positively correlated with temperature•Soil moisture results were not consistent•Sensible heat fluxes were negatively correlated with temperature•Snow depths were negatively correlated with temperature•Snowmelt generally occurs earlier in the spring with increased temperaturesExperiment•increasing precipitation will increase runoff• will increase infiltration•will increase soil moisture•will increase and delay snow meltScenario 2: Precipitation change scenarioHypothesis:Observed data:•Runoff•Infiltration•Soil moisture•Snow meltExperimentScenario 2: Precipitation change scenarioMonthly Runoff for PrecipitationScenarios0501001502002503003504001 2 3 4 5 6 7 8 9 10 11 12MonthRunoff [mm/month]HALFORIGINALDOUBLEMonthly Infiltration for PrecipitationScenarios-500501001502002503003504001 2 3 4 5 6 7 8 9 10 11 12MonthInfiltration [mm/month]HALFORIGINALDOUBLEMonthly Snowmelt for PrecipitationScenarios01002003004005006001 2 3 4 5 6 7 8 9 10 11 12MonthSnowmelt [mm/month]HALFORIGINALDOUBLEMonthly Snowdepth for PrecipitationScenarios00.20.40.60.811.21.41.61.81 2 3 4 5 6 7 8 9 10 11 12MonthSnowdepth [m]HALFORIGINALDOUBLEExperimentScenario 2: Precipitation change scenarioAverage Monthly Soil Water for PrecipitationScenarios0501001502002503003501 2 3 4 5 6 7 8 9 10 11 12MonthSoil Water [mm]HALFORIGINALDOUBLE2002202402602803003203400 100 200 300 400 500 600 700Days from Nov. 16Avg Soil Moisture (first 8 layers) ) ORIGINALHOTCOLDDRYWETConclusions - Precipitation change scenario•Precipitation is positively correlated with:–Runoff–Snowmelt–Infiltration–Snow depth•Soil moisture drives the cycle •High soil moisture during “dry” scenario during winter months–Due to snow or model
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