The influence of North American snow cover on climate

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1993

OSTI ID:6927829

Ni Chaoimh, U M

The Community Climate Model (CCM1) of the National Center for Atmospheric Research (NCAR) was used to simulate the influence of different snow-fall rates on climate. Three simulations were conducted; a control simulation, one with a doubled snow-fall rate over North America and one with a halved snow-fall rate over North America. The condensation rate was not changed. Simulations were averaged over five model years. The influence of snow cover increased from January to March. When snow-fall was doubled surface temperatures were generally lower. However, in late spring surface temperatures were higher in northerly latitudes when there was more snow. Sea-level pressures were higher in the regions where temperatures were lower. There was an area of lower sea-level pressures off the east coast of North America. Upper level heights were greater in both the halved and doubled snow-fall simulations than in the control simulations, due in the former case to greater thicknesses and in the latter to higher surface pressures. Overall, heights were lower in the doubled than in the halved snow-fall case. The influence of snow cover was seen up to 200 mb. In early summer, there was increased surface wetness with increased snow-fall amount. This maintained lower surface temperatures over the continent until August. In early summer sea-level pressures were also affected by the change in surface wetness. Many of the influences noted during this experiment are similar to those which have been observed. The results of this experiment indicate that the conditions which accompany the snow are directly attributable to the snow cover on the surface.

• Research Organization: Ohio State Univ., Columbus, OH (United States)
• OSTI ID: 6927829
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ATMOSPHERIC PRECIPITATIONS
CLIMATE MODELS
COMPUTERIZED SIMULATION
MATHEMATICAL MODELS
METEOROLOGY
NORTH AMERICA
SEASONAL VARIATIONS
SIMULATION
SNOW
VARIATIONS
WEATHER