1. Katja Friedrich Associate Professor Dept. of Atmospheric and Oceanic Sciences, U. of Colorado Science Plan & Experimental Design

2. O VERARCHING G OAL Develop methods and tools to estimate evaporation of water from reservoirs throughout the year depending on the reservoir’s latitude, elevation, regional climate, and shape and to predict reservoir evaporation throughout the year and under a changing climate

3. O BJECTIVES 1.Quantify factors determining water evaporation under various climate conditions and throughout the year a.Water conditions (temperature, mixing, inflow/outflow temperatures, waves, ice cover/duration) b.Atmospheric conditions (wind speed, humidity, air temperature, mass and humidity fluxes) c.Environmental conditions (vegetation, snow cover, surrounding topography, slope, soil moisture) 2.Develop a heuristic method to quantify reservoir evaporation based findings from #1 3.Develop a sophisticated reservoir (lake) model coupled with a community atmospheric and hydrological model 4.Test heuristic and numerical models in different climate regimes and conditions throughout the year

4. O BSERVATIONS O BSERVE SPATIAL AND TEMPORAL VARIABILITY ParameterInstrumentation Reservoir (above and under water) Wind, humidity, temperature profileLidar, radiometer, sodar, wind profiler Moisture and mass fluxes/EvaporationEddy covariance systems, pan Water temperature (surface)Buoys, fixed platforms Underwater currentBuoys, fixed platforms Environment Wind profile (surface roughness)Lidar, tower, wind profiler, soundings, UAV, tethersonde Humidity & temperature profilesRadiometer, SODAR, tower, soundings, UAV, tethersonde Moisture and mass fluxesEddy covariance systems, UAV, soil moisture measurements

5. A PPROACH 1.Permanent/mobile test bed(s) with multi-platform facility similar to the DOE Atmospheric Radiation Measurement (ARM) facility or AmeriFlux; What would be a good test bed location(s)? What would be the requirements for a testbed? Which instruments have highest priority? 2.Combination of permanent facilities plus research experiments with limited duration; 3.Development of a community reservoir model and a community modeling approach; testing model over testbed What model do we want to use? How will maintain and run the model? Who will develop the reservoir model? 4.Develop estimations and forecasts of reservoir evaporation

6. GROSS RESERVOIR

7. LAKE MEAD

8. L OGISTICS & O UTREACH 1.Project and data management 2.Project planning, coordination, and support 3.Educational benefits and outreach

9. N EXT S TEPS 1.Create a press release and 1-page summary for program managers 2.Create a white paper and a short workshop summary for EOS; presentations at AGU or AMS 3.Allocate funding sources; develop science/experimental plan for proposal submission 4.Find testbed and equip with instruments 5.Develop modeling plan

10. F UNDING SOURCES 1.NSF – basic research, model development, field campaign (very limited time) 2.DOE – Terrestrial Ecosystem Science PNNL Hydrology Technical Group (http://hydrology.pnnl.gov/ )http://hydrology.pnnl.gov/ 3.NASA Surface Hydrology (http://weather.msfc.nasa.gov/surface_hydrology/ )http://weather.msfc.nasa.gov/surface_hydrology/ 4.USBR 5.??

11. Q UESTIONS 1.What are the main research questions and objectives that need to be addressed? 2.What atmospheric, limnological, and hydrological variables need to be measured of which sampling interval in order to address the research objectives and assess model performance? 3.Which new or current instruments are needed for a short-term and long-term measurement campaign? What is the design for a short- term versus long-term combined measurement and modeling campaign? 4.What would be a good target region to perform an experiment? Can leverage onto existing measurements? 5.Which funding sources can be targeted for long- and short-term research efforts? 6.What would be the next step or timeline to design an experiment?

12. N UMERICAL M ODELING -WRF-Hydro (evaporation output): The Monin-Obukhov similarity profile relationship for surface stress and latent heat fluxes (Miyakoda and Sirutis, 1986); Land -surface evaporation has three components (direct evaporation from the soil and -canopy, and transpiration from vegetation) following the formulation of Pan and -Mahrt (1987) (3). (This scheme has been preliminarily tested for WRF- NMM.) -Use WRF output as boundary conditions for 1D lake model (offline) -WRF + 1D CLM 4.5 lake model CESM (10 layers