Open AccessCrop Wind Energy Experiment (CWEX): Observations of Surface-Layer, Boundary Layer, and Mesoscale Interactions with a Wind Farm
Author(s) -
D. A. Rajewski,
Eugene S. Takle,
Julie K. Lundquist,
Steven Oncley,
John H. Prueger,
Thomas Horst,
Michael E. Rhodes,
Richard Pfeiffer,
Jerry L. Hatfield,
Kristopher K. Spoth,
Russell Doorenbos
Publication year - 2013
Publication title -
bulletin of the american meteorological society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.367
H-Index - 197
eISSN - 1520-0477
pISSN - 0003-0007
DOI - 10.1175/bams-d-11-00240.1
Subject(s) - environmental science , mesoscale meteorology , boundary layer , planetary boundary layer , wind power , meteorology , wind speed , weather research and forecasting model , atmospheric sciences , wind profile power law , wind shear , turbine , turbulence , geology , geography , aerospace engineering , engineering , electrical engineering
Perturbations of mean and turbulent wind characteristics by large wind turbines modify fluxes between the vegetated surface and the lower boundary layer. While simulations have suggested that wind farms could significantly change surface fluxes of heat, momentum, momentum, moisture, and CO2 over hundreds of square kilometers, little observational evidence exists to test these predictions. Quantifying the influences of the “turbine layer” is necessary to quantify how surface fluxes are modified and to better forecast energy production by a wind farm. Changes in fluxes are particularly important in regions of intensely managed agriculture where crop growth and yield are highly dependent on subtle changes in moisture, heat, and CO2. Furthermore, speculations abound about the possible mesoscale consequences of boundary layer changes that are produced by wind farms. To address the lack of observations to answer these questions, we developed the Crop Wind Energy Experiment (CWEX) as a multiagency, multiuniversity field program in central Iowa. Throughout the summer of 2010, surface fluxes were documented within a wind farm test site and a 2-week deployment of a vertically pointing lidar quantified wind profiles. In 2011, we expanded measurements at the site by deploying six flux stations and two wind-profiling lidars to document turbine wakes. The results provide valuable insights into the exchanges over a surface that has been modified by wind turbines and a basis for a more comprehensive measurement program planned for the summer in 2014.