Meteorologische Zeitschrift (Oct 2017)

Surface energy fluxes during the total solar eclipse over Ny-Ålesund, Svalbard, on 20 March 2015

  • Alexander Schulz,
  • Carsten Schaller,
  • Marion Maturilli,
  • Julia Boike,
  • Christoph Ritter,
  • Thomas Foken

DOI
https://doi.org/10.1127/metz/2017/0846
Journal volume & issue
Vol. 26, no. 4
pp. 431 – 440

Abstract

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On 20 March 2015, a total solar eclipse occurred over Ny-Ålesund (78.9° N, 11.9° E), Svalbard, under ideal conditions with clear sky. The cycle of the radiation fluxes is comparable with other experiments during eclipses, with even the upward longwave radiation showing significant changes, with a delay to the shortwave radiation and a slowly linear increase after the totality. Also, under polar conditions, an increase of the wind velocity before and a decrease after the totality was found, which is an indicator of the generation of an “Eclipse cyclone”. This change of the wind direction generated a local wind system with a near-surface-layer katabatic flow. During the eclipse, a remarkably large sensible heat flux was observed. The turbulent fluxes were analysed using a wavelet technique with 1-minute time resolution, which is the ideal method for investigating these highly non-steady conditions. No influences on the boundary layer structure as measured with radiosondes were found, with the exception of a wind direction change during the eclipse cyclone below the shallow inversion layer.

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