Snowpack radiative heating: Influence on Tibetan Plateau climate

Solar absorption decays exponentially with depth in snowpacks. However, most climate models constrain all snowpack absorption to occur uniformly in the top‐most snow layer. We show that 20–45% of solar absorption by deep snowpacks occurs more than 2 cm beneath the surface. Accounting for vertically‐resolved solar heating alters steady‐state snow mass without changing bulk snow albedo, and ice‐albedo feedback amplifies this effect. Vertically‐resolved snowpack heating reduces winter snow mass on the Tibetan Plateau by 80% in one GCM, and significantly increases 2 m air temperature. These changes significantly reduce model‐measurement discrepancies. Our results demonstrate that snowpack radiative heating plays a significant role in regulating surface climate and hydrology. More accurate snowpack radiation has the potential to improve predictions of related climate processes, such as spring runoff and the Asian Monsoon.

[1]  John T. Fasullo,et al.  A Stratified Diagnosis of the Indian Monsoon—Eurasian Snow Cover Relationship , 2004 .

[2]  M. Mikami,et al.  Effect of snow cover on threshold wind velocity of dust outbreak , 2004 .

[3]  Thomas H. Painter,et al.  Incorporating remotely‐sensed snow albedo into a spatially‐distributed snowmelt model , 2004 .

[4]  Peter E. Thornton,et al.  Technical Description of the Community Land Model (CLM) , 2004 .

[5]  W. Collins,et al.  Description of the NCAR Community Atmosphere Model (CAM 3.0) , 2004 .

[6]  Tong Wu,et al.  The Relation between the Tibetan Winter Snow and the Asian Summer Monsoon and Rainfall: An Observational Investigation. , 2003 .

[7]  T. Painter,et al.  Retrieval of subpixel snow-covered area and grain size from imaging spectrometer data , 2003 .

[8]  Julienne C. Stroeve,et al.  New methods to infer snow albedo from the MISR instrument with applications to the Greenland ice sheet , 2002, IEEE Trans. Geosci. Remote. Sens..

[9]  Teruo Aoki,et al.  Effects of snow physical parameters on spectral albedo and bidirectional reflectance of snow surface , 2000 .

[10]  P. Jones,et al.  Representing Twentieth-Century Space–Time Climate Variability. Part I: Development of a 1961–90 Mean Monthly Terrestrial Climatology , 1999 .

[11]  Diana Verseghy,et al.  Snow Cover and Snow Mass Intercomparisons of General Circulation Models and Remotely Sensed Datasets , 1996 .

[12]  Stephen G. Warren,et al.  Solar-heating rates and temperature profiles in Antarctic snow and ice , 1993, Journal of Glaciology.

[13]  R. Jordan A One-dimensional temperature model for a snow cover : technical documentation for SNTHERM.89 , 1991 .

[14]  Thomas C. Grenfell,et al.  A radiative transfer model for sea ice with vertical structure variations , 1991 .

[15]  C. McKay,et al.  Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres , 1989 .

[16]  Dudley F. Foster,et al.  Global Snow Depth Climatology , 1988 .

[17]  Stephen G. Warren,et al.  Optical Properties of Snow , 1982 .

[18]  S. Warren,et al.  A Model for the Spectral Albedo of Snow. I: Pure Snow , 1980 .

[19]  R. C. Lile,et al.  Meteorological Studies at Plateau Station, Antarctica , 1977 .

[20]  H. F. Blanford II. On the connexion of the Himalaya snowfall with dry winds and seasons of drought in India , 1884, Proceedings of the Royal Society of London.