hrbwa dmmgjm 22_oct2012

Current and potential cloud seeding in the Humboldt River Basin

Mark Green, John Mejia and David MitchellDesert Research Institute

WY2013 Ruby Mountains Project Area

WY2013 Tahoe-Truckee Project Area

WY2013 Walker Basin Project Area

Figure 3. Map showing several of the mountainous areas (blue shading) considered in the DRI cloud seeding feasibility study for eastern Nevada. The prototype project is planned for the northern portion of the Schell Creek Range in the center of the map. Possible seeding sites tested with a plume dispersion model are indicated by blue pins and green flags. SNOTEL or snow course sites are shown by red Xs. Red and yellow shaded areas represent specific creek drainages and purple triangles show stream gauge locations.

Eastern Nevada Project Area (seeding starting in WY2014)

Number of generators

Total cost

7 $265K

6 $242K

5 $219K

4 $197K

3 $174K

Start with SNWA WY2013 funding of $252KApply 5% increase for inflation= $265KFor 7 generators, about $38K per generator for full networkAssume reduced network size saves 60% of average per cost when reducing network size.

FY 2014 Cost estimate for continuing Ruby Mountains seeding operations

Costs of starting any programs in new areas high first year due to site establishment costs

Map of SNOTEL sites gives good indication of potential seeding areas

Granite Peak Snotel site at 8543’ in Santa Rosa Mtns

Spring 2011 had over 100” snow depth

Bear Creek SNOTEL site 8040’ in the Jarbidge Range

Jack’s Peak SNOTEL site -8420’ near the headwaters of the North Fork Humboldt River, Independence Mountains

Spring 2011 had over 100” snow depth

In the past DRI operated cloud seeding generators targeting the Independence Mountains north of Elko and nearby areas

Big Creek Sum SNOTEL site at 8695’ in the Toiyabe Range, headwaters of the Reese River, a tributary of the Humboldt River

Seeding has been done by DRI in the Toiyabe Range

Use of the Weather Research and Forecasting Model (WRF)In Cloud Seeding Research and Operations:

Our overall motivation is to use the model to betterunderstand/track the evolution of cloud seeding aerosol in timeand space. Current uses of WRF include:

1) Selection of cloud seeding generator sites in planning future Programs

2) Decision making support for when to conduct cloud seeding

3-day forecast of some criteria used to decide whether to commence cloud seeding, using the WRF Model at DRI.

This morning’s Radar image and wind profile from NWS Elko- let’s us know if precipitation is occurring and if winds are in the right direction

Mesowest display of temperature, precipitation, winds and Radar for the Ruby Mountains area

Figure 3. Map showing several of the mountainous areas (blue shading) considered in the DRI cloud seeding feasibility study for eastern Nevada. The prototype project is planned for the northern portion of the Schell Creek Range in the center of the map. Possible seeding sites tested with a plume dispersion model are indicated by blue pins and green flags. SNOTEL or snow course sites are shown by red Xs. Red and yellow shaded areas represent specific creek drainages and purple triangles show stream gauge locations.

Testing of Generator Sites in Eastern Nevada Project Area

Summary

1. WRF provides advance knowledge of when favorable cloud seeding conditions are likely to develop.

2. WRF combined with a plume dispersion model greatly improvesour ability to locate cloud seeding generators in areas that willoptimize snowfall amounts in targeted areas.

3. Location of generator sites also depends on accessibility and authorization of land owner or responsible agency.