P16  WRF Dynamically Downscaled Simulation of Projected Climate in the Missouri River Basin: 2000-2050

Norton, Parker and John Stamm, USGS South Dakota Water Science Center

The Weather Research and Forecasting Model (WRF) was used to simulate climate at a 36 kilometer resolution for North America for 2000–2050, based on Community Climate System Model 3.0 SRESA2 scenario boundary and initial conditions. Estimation of lake surface temperatures was based on daily-average land surface air temperature as a proxy coupled with a USGS land use dataset that identifies lakes. Other adjustments include updates of deep soil temperature using a 150 day lag, smoothing at domain boundaries, and a specified boundary width of 10 grid cells.  Physics options include WSM6 microphysics, CAM shortwave and longwave radiation, Monin–Obukhov surface layer scheme, Noah land surface model, YSU boundary layer, and Kain–Fritsch cumulus scheme. Validation of temperature and precipitation for grid points within the Missouri River Basin (MRB) was based on comparison with output from the Parameter-elevation Regressions on Independent Slopes Model. WRF simulation for the MRB temperatures indicate increases in spring, summer, and autumn with greatest increase in autumn (1.9–3.1¡C).  Summer precipitation in the MRB is projected to decrease 50 mm (4–95 mm at 95% confidence interval), with no clear trend indicated for other seasons.