Sky longwave radiation on tropical Andean glaciers: parameterization and sensitivity to atmospheric variables

$37.03 plus tax (Refund Policy)

Buy Article:

Abstract:

In mountain environments, longwave radiation provides large amounts of melt energy for high-albedo snow surfaces and can dominate in the energy balance of snow or glacier surfaces under cloudy skies. This study examines the atmospheric controls of sky longwave radiation at Glaciar Zongo, Bolivia (16°15′S, 5060 m a.s.l.) over an entire year to derive a parameterization suitable for melt studies. Tropical glaciers are characterized by a pronounced seasonality of longwave radiation, due to cloud emissions during the wet season that strongly enhance the small emissivity of the thin and dry clear-sky atmosphere at very high altitudes. Clear-sky radiation is well simulated as a function of air temperature and humidity, but changes in humidity atmospheric profiles from daytime to night-time entail different optimized coefficients for hourly and daily data. Cloud emission, which enhances clear-sky emissivity by up to 55%, with an average of 20%, is estimated using daily atmospheric transmissivity for solar radiation. Partial correlations show that in high mountains cloud emissions control the variations of longwave radiation, far more than clear-sky emissivity and temperature of the emitting atmosphere. An independent test on Glaciar Antizana in the humid tropics of Ecuador (0°28′S, 4860 m a.s.l.) indicates that the parameterization is robust for the Central Andes.

Document Type: Research Article

DOI: http://dx.doi.org/10.3189/002214310794457182

Publication date: December 1, 2010

More about this publication?
  • The Journal of Glaciology is published six times per year. It accepts submissions from any discipline related to the study of snow and ice. All articles are peer reviewed. The Journal is included in the ISI Science Citation Index.
  • Editorial Board
  • Information for Authors
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more