Articles | Volume 12, issue 2
Biogeosciences, 12, 433–451, 2015
Biogeosciences, 12, 433–451, 2015

Research article 23 Jan 2015

Research article | 23 Jan 2015

Components of near-surface energy balance derived from satellite soundings – Part 1: Noontime net available energy

K. Mallick1, A. Jarvis2, G. Wohlfahrt3,*, G. Kiely4, T. Hirano5, A. Miyata6, S. Yamamoto7, and L. Hoffmann1 K. Mallick et al.
  • 1Environmental Research and Innovation (ERIN), Luxembourg Institute of Science and Technology (LIST), L4422, Belvaux, Luxembourg
  • 2Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
  • 3Institute of Ecology, University of Innsbruck, 6020 Innsbruck, Austria
  • 4Hydrometeorology Research Group, Department of Civil and Environmental Engineering, University College Cork, Ireland
  • 5Division of Environmental Resources, Research Faculty of Agriculture, Hokkaido University, Hokkaido, Japan
  • 6National Institute for Agro-Environmental Sciences, Tsukuba, Japan
  • 7Graduate School of Environmental Science, Okayama University Tsushimanaka3-1-1, Okayama 700-8530, Japan
  • *now at: European Academy of Bolzano, 39100 Bolzano, Italy

Abstract. This paper introduces a relatively simple method for recovering global fields of monthly midday (13:30 LT) near-surface net available energy (the sum of the sensible and latent heat flux or the difference between the net radiation and surface heat accumulation) using satellite visible and infrared products derived from the AIRS (Atmospheric Infrared Sounder) and MODIS (MODerate Resolution Imaging Spectroradiometer) platforms. The method focuses on first specifying net surface radiation by considering its various shortwave and longwave components. This was then used in a surface energy balance equation in conjunction with satellite day–night surface temperature difference to derive 12 h discrete time estimates of surface system heat capacity and heat accumulation, leading directly to retrieval for surface net available energy. Both net radiation and net available energy estimates were evaluated against ground truth data taken from 30 terrestrial tower sites affiliated with the FLUXNET network covering 7 different biome classes. This revealed a relatively good agreement between the satellite and tower data, with a pooled root-mean-square deviation of 98 and 72 W m−2 for monthly 13:30 LT net radiation and net available energy, respectively, although both quantities were underestimated by approximately 25 and 10%, respectively, relative to the tower observation. Analysis of the individual shortwave and longwave components of the net radiation revealed the downwelling shortwave radiation to be main source of this systematic underestimation.

Short summary
This paper demonstrates a novel analytical method for recovering global fields noontime near-surface net available energy (the sum of the sensible and latent heat flux) and ground heat flux using day-night land surface temperature and net radiation combining AIRS and MODIS optical, thermal and atmospheric data. This method could potentially overcome the stumbling blocks associated with the empirical parameterisations for determining the ground heat flux in global evapotranspiration modelling.
Final-revised paper