Observations and Numerical Simulation of the Effects of the 21 August 2017 North American Total Solar Eclipse on Surface Conditions and Atmospheric Boundary-Layer Evolution

Details

• Journal Title:
  Boundary-Layer Meteorology
• Personal Author:
  Buban, Michael S. ; Lee, Temple R. ; Dumas, Edward J. ; Baker, C. Bruce ; Heuer, Mark
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; ARL (Air Resources Laboratory) ; CIMMS (Cooperative Institute for Mesoscale Meteorological Studies)
• Description:
  We present unique observations of a total solar eclipse from a small unmanned aircraft system (sUAS) platform that was operated during the 21 August 2017 North American solar eclipse. The observations were collected near Ten Mile, Tennessee, where eclipse totality lasted 2 min 38 s. A 2-m micrometeorological tripod was erected on-site to measure surface and air temperature, near-surface water vapour, incoming and outgoing shortwave and longwave radiative fluxes, and turbulent fluxes. The sUAS platform and micrometeorological tripod observations indicate significant cooling below a height of 50 m above ground level (a.g.l.) during and shortly after totality. Near-surface temperatures do not return to pre-eclipse values until about 60 min following totality. Above about 50 m a.g.l., smaller temperature changes are observed during the eclipse, as the duration of the eclipse has less influence on deeper boundary-layer turbulence. Additionally, the sensible heat flux becomes slightly negative around totality, and the turbulence kinetic energy and vertical velocity variance concurrently decrease. The evolution of the near-surface meteorological fields are investigated in more detail using a large-eddy simulation (LES) model. The simulations generally reproduce the observations well, in terms of the timing and magnitude of changes in temperature, moisture and sensible and latent heat fluxes. However, the LES model slightly underestimates the diurnal range and decrease in temperature during the eclipse while overestimating the sensible heat fluxes.
• Source:
  Boundary-Layer Meteorology, 171(2), 257-270.
• DOI:
  https://doi.org/10.1007/s10546-018-00421-4
• Document Type:
  Journal Article
• Rights Information:
  Accepted Manuscript
• Rights Statement:
  The NOAA IR provides access to this content under the authority of the government's retained license to distribute publications and data resulting from federal funding. While users may legally access this content, the copyright owners retain rights that govern the reproduction, redistribution, and re-use of this work. The user is solely responsible for complying with applicable copyright law.
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:c618d3888f2908aba454f5b181aa3509e617910247923bc35ae30d817f47287a682a0c10a7800631462881b674fbd2fafb5ea2adfaeb052abf50eec314a2c27c
• Download URL:
  https://repository.library.noaa.gov/view/noaa/25541/noaa_25541_DS1.pdf
• File Type:
  [PDF - 3.93 MB ]