Journal cover Journal topic
The Cryosphere An interactive open-access journal of the European Geosciences Union
doi:10.5194/tc-2016-258
© Author(s) 2016. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
15 Nov 2016
Review status
This discussion paper is under review for the journal The Cryosphere (TC).
Process-level model evaluation: A Snow and Heat Transfer Metric
Andrew G. Slater1, David M. Lawrence2, and Charles D. Koven3 1NSIDC/CIRES, University of Colorado, Boulder, 80303, USA
2National Center for Atmospheric Research, Boulder, 80305, USA
3Lawrence Berkeley National Laboratory, Berkeley, 94720, USA
Abstract. Land models require evaluation in order to understand results and guide future development. Examining functional relationships between model variables can provide insight into the ability of models to capture fundamental processes and aid in minimizing uncertainties or deficiencies in model forcing. This study quantifies the proficiency of land models to appropriately transfer heat from the soil through a snowpack to the atmosphere during the cooling season (Northern Hemisphere: October–March). Using the basic physics of heat diffusion, we investigate the relationship between seasonal amplitudes of soil versus air temperatures due to insulation from seasonal snow. Observations demonstrate the anticipated exponential relationship of attenuated soil temperature amplitude with increasing snow depth and indicate that the marginal influence of snow insulation diminishes beyond an "effective snow depth" of about 50 cm. A Snow and Heat Transfer Metric (SHTM) is developed to quantify model skill compared to observations. Land models within the CMIP5 experiment vary widely in SHTM scores and deficiencies can often be traced to model structural weaknesses. The SHTM value for individual models is stable over 150 years of climate 1850–2005, indicating that the metric is insensitive to climate forcing and can be used to evaluate each model's representation of the insulation process

Citation: Slater, A. G., Lawrence, D. M., and Koven, C. D.: Process-level model evaluation: A Snow and Heat Transfer Metric, The Cryosphere Discuss., doi:10.5194/tc-2016-258, in review, 2016.
Andrew G. Slater et al.
Andrew G. Slater et al.
Andrew G. Slater et al.

Viewed

Total article views: 154 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
105 33 16 154 10 20

Views and downloads (calculated since 15 Nov 2016)

Cumulative views and downloads (calculated since 15 Nov 2016)

Viewed (geographical distribution)

Total article views: 154 (including HTML, PDF, and XML)

Thereof 154 with geography defined and 0 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 22 Feb 2017
Publications Copernicus
Download
Short summary
This work defines a metric that for evaluation of a specific model process, namely, heat transfer through snow into soil. Heat transfer through snow regulates the difference in air temperature versus soil temperature. Accurate representation of the snow heat transfer process is critically important for accurate representation of the current and future state of permafrost. Utilizing this metric, we can clearly identify models that can and cannot reasonably represent snow heat transfer.
This work defines a metric that for evaluation of a specific model process, namely, heat...
Share