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Title: Spatial and temporal variability of turbulence dissipation rate in complex terrain

Abstract

To improve parameterizations of the turbulence dissipation rate (ϵ) in numerical weather prediction models, the temporal and spatial variability of ϵ must be assessed. In this study, we explore influences on the variability of ϵ at various scales in the Columbia River Gorge during the WFIP2 field experiment between 2015 and 2017. We calculate ϵ from five sonic anemometers all deployed in a ~4 km2 area as well as from two scanning Doppler lidars and four profiling Doppler lidars, whose locations span a ~300 km wide region. We retrieve ϵ from the sonic anemometers using the second-order structure function method, from the scanning lidars with the azimuth structure function approach, and from the profiling lidars with a novel technique using the variance of the line-of-sight velocity. The turbulence dissipation rate shows large spatial variability, even at the microscale, especially during nighttime stable conditions. Orographic features have a strong impact on the variability of ϵ, with the correlation between ϵ at different stations being highly influenced by terrain. ϵ shows larger values in sites located downwind of complex orographic structures or in wind farm wakes. A clear diurnal cycle in ϵ is found, with daytime convective conditions determining values over anmore » order of magnitude higher than nighttime stable conditions. ϵ also shows a distinct seasonal cycle, with differences greater than an order of magnitude between average ϵ values in summer and winter.« less

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3];  [4]; ORCiD logo [4]; ORCiD logo [5]
  1. Univ. of Colorado, Boulder, CO (United States). Dept. of Atmospheric and Oceanic Sciences
  2. Univ. of Colorado, Boulder, CO (United States). Dept. of Atmospheric and Oceanic Sciences; National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Univ. of Notre Dame, IN (United States)
  4. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  5. Cooperative Inst. for Research in Environmental Sciences, Boulder, CO (United States)
Publication Date:
Research Org.:
National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Univ. of Colorado, Boulder, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Wind Energy Technologies Office; National Science Foundation (NSF)
OSTI Identifier:
1510420
Report Number(s):
NREL/JA-5000-73831
Journal ID: ISSN 1680-7324
Grant/Contract Number:  
AC36-08GO28308; AC06-76RL01830; AGS-1554055
Resource Type:
Accepted Manuscript
Journal Name:
Atmospheric Chemistry and Physics (Online)
Additional Journal Information:
Journal Name: Atmospheric Chemistry and Physics (Online); Journal Volume: 19; Journal Issue: 7; Journal ID: ISSN 1680-7324
Publisher:
European Geosciences Union
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES

Citation Formats

Bodini, Nicola, Lundquist, Julie K., Krishnamurthy, Raghavendra, Pekour, Mikhail, Berg, Larry K., and Choukulkar, Aditya. Spatial and temporal variability of turbulence dissipation rate in complex terrain. United States: N. p., 2019. Web. doi:10.5194/acp-19-4367-2019.
Bodini, Nicola, Lundquist, Julie K., Krishnamurthy, Raghavendra, Pekour, Mikhail, Berg, Larry K., & Choukulkar, Aditya. Spatial and temporal variability of turbulence dissipation rate in complex terrain. United States. https://doi.org/10.5194/acp-19-4367-2019
Bodini, Nicola, Lundquist, Julie K., Krishnamurthy, Raghavendra, Pekour, Mikhail, Berg, Larry K., and Choukulkar, Aditya. Thu . "Spatial and temporal variability of turbulence dissipation rate in complex terrain". United States. https://doi.org/10.5194/acp-19-4367-2019. https://www.osti.gov/servlets/purl/1510420.
@article{osti_1510420,
title = {Spatial and temporal variability of turbulence dissipation rate in complex terrain},
author = {Bodini, Nicola and Lundquist, Julie K. and Krishnamurthy, Raghavendra and Pekour, Mikhail and Berg, Larry K. and Choukulkar, Aditya},
abstractNote = {To improve parameterizations of the turbulence dissipation rate (ϵ) in numerical weather prediction models, the temporal and spatial variability of ϵ must be assessed. In this study, we explore influences on the variability of ϵ at various scales in the Columbia River Gorge during the WFIP2 field experiment between 2015 and 2017. We calculate ϵ from five sonic anemometers all deployed in a ~4 km2 area as well as from two scanning Doppler lidars and four profiling Doppler lidars, whose locations span a ~300 km wide region. We retrieve ϵ from the sonic anemometers using the second-order structure function method, from the scanning lidars with the azimuth structure function approach, and from the profiling lidars with a novel technique using the variance of the line-of-sight velocity. The turbulence dissipation rate shows large spatial variability, even at the microscale, especially during nighttime stable conditions. Orographic features have a strong impact on the variability of ϵ, with the correlation between ϵ at different stations being highly influenced by terrain. ϵ shows larger values in sites located downwind of complex orographic structures or in wind farm wakes. A clear diurnal cycle in ϵ is found, with daytime convective conditions determining values over an order of magnitude higher than nighttime stable conditions. ϵ also shows a distinct seasonal cycle, with differences greater than an order of magnitude between average ϵ values in summer and winter.},
doi = {10.5194/acp-19-4367-2019},
journal = {Atmospheric Chemistry and Physics (Online)},
number = 7,
volume = 19,
place = {United States},
year = {Thu Apr 04 00:00:00 EDT 2019},
month = {Thu Apr 04 00:00:00 EDT 2019}
}

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Works referencing / citing this record:

Estimation of turbulence dissipation rate from Doppler wind lidars and in situ instrumentation for the Perdigão 2017 campaign
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