6th International Conference Energy & Meteorology: Abstract Submission

Summary of Results from the Second Wind Forecast Improvement Project (WFIP2) (792)

James Wilczak 1 , Laura Bianco 2 , Irina Djalalova 2 , Katherine McCaffrey 2 , Joseph Olson 2 , Mark Stoelinga 3 , Larry Berg 4 , Aditya Choukulkar 2 , Yelena Pichugina 2 , Robert Banta 2 , Caroline Draxl 5 , Tim Bonin 2 , Harindra Fernando 6 , Eric Grimit 3 , Jaymes Kenyon 2 , Julie Lundquist 2 , Jim McCaa 3 , Paytsar Muradyan 7 , Justin Sharp 8 , William Shaw 4 , Dave Turner 1 , Sonia Wharton 9 , Rochelle Worsnop 2
  1. NOAA/Earth Systems Research Laboratory, Boulder, CO, United States
  2. University of Colorado, Boulder, Colorado, United States
  3. Vaisala Inc. , Seattle, Washington, United States
  4. DOE/Pacific Northwest National Laboratory, Richland, Washington, United States
  5. DOE/National Renewable Energy Laboratory, Golden, Colorado, United States
  6. University of Notre Dame, Notre Dame, Indiana, United States
  7. DOE/Argonne National Laboratory, Lemont, Illinois, United States
  8. Sharly Focused, LLC., Portland, Oregon, United States
  9. DOE/Lawrence Livermore National Laboratory, Livermore, California, United States

The second Wind Forecast Improvement Project (WFIP 2) was an 18-month (October 2015 - March 2017) DOE and NOAA led multi-agency project conducted in Oregon and Washington states. The goals of WFIP2 were to improve our understanding of flows in complex terrain, translate that improved understanding into better physical parameterization schemes in numerical weather prediction models, and ultimately improve the skill of those models at predicting boundary layer winds. As part of WFIP2 a field campaign took place in the Columbia River Basin east of the Cascade mountains in eastern Washington and Oregon states, an area with extremely complex terrain. The basin is surrounded by high terrain on all sides, resulting in cold pools, gap flows, mountain waves, mountain wakes, and other types of terrain-influenced circulations occurring at many different scales.  All of these vary in intensity and behavior depending on the atmospheric conditions, and all present unique challenges to short-term forecasting for wind energy in the region. 

 

We describe the final results of the WFIP2 study, focusing on three primary weather phenomena were identified as the sources of large and persistent wind forecast errors:

  • Cold pools.  These routinely develop within the Columbia Basin east of the Cascades in the cold season and are associated with light or stagnant flow. The mix-out of these cold pools is one of the greatest challenges of wind energy forecasting in this region, as the mix-out causes large increases or ramps in wind power production.
  • Gap flows.   WFIP2 focused on warm-season, westerly gap flows forced by inland daytime heating but that are also influenced by synoptic-scale transient weather patterns. These strong gap flows drive reliably large amounts of wind power production, but their onset and decay are not well-predicted.
  • Mountain waves and wakes.  Under conditions of strong, deep westerly flow, primarily in the cold and transition seasons, flow over the Cascade crest as well as local topographic features in the Columbia Basin can produce a variety of gravity wave and topographic wake responses.  Subtle shifts in the position of these waves strongly affect production at individual wind farms.  Also, large wakes in the lee of Mounts Adams and Hood can produce meandering low-wind bands that extend hundreds of km downwind of these volcanoes.

 

Observations and model results from WFIP2 will be used to describe each of these three phenomena, including what we have learned about their structure and evolution, model parameterization changes that have improved our ability to forecast them, and modeling challenges that remain.