February 28, 2007
GCRIO Program Overview
Our extensive collection of documents.
Archives of the
Global Climate Change Digest
A Guide to Information on Greenhouse Gases and Ozone Depletion
Published July 1988 through June 1999
FROM VOLUME 12, NUMBER 4, APRIL 1999
Simulated Climate Change Effects on Year-Round Water Temperatures in
Temperate Zone Lakes, H. G. Stefan, X. Fang, and M. Hondzo,Climatic
Change 40, 547-576 (1998).
Computer simulations indicate that a doubling of CO2 would
delay ice formation up to 20 days and shorten the ice-cover period up to
58 days in temperate lakes and produce temperature modifications
throughout the year, with water surface temperatures increasing 3 to 4°
C and summer stratification becoming stronger.
The Natural Fluctuations of Firn Densification and Their Effect on
the Geodetic Determination of Ice Sheet Mass Balance, R. J. Arthern
and D. J. Wingham,Climatic Change 40, 605-624 (1998).
A model of firn density was developed, checked against observational
data from Antarctica and Greenland, and found to be accurate within 10%.
The model was then used to determine the effects of natural climate
variation on firn density. Temperature effects on firn density are
transmitted by conduction through the upper 30 m of firn; accumulation
effects immediately affect only the upper 10 m. In both cases, the effects
on densification were so small that they would not unduly affect the use
of the geodetic method of measuring the ice-sheet mass balance.
Model Computations of the Impact of Climatic Change on the Windthrow
Risk of Trees, H. Peltola, S. Kellomäki, and H. Väisänen,Climatic
Change 40, 17-36 (1999).
Mean winds of 11 m/s are enough to uproot Scots pines when the soil is
not frozen; freezing helps hold the roots in place. Monthly wind-speed
statistics for Finland for 1961 to 1990 were used in conjunction with
model-derived estimates of the effects of a 4° C increase in mean
annual temperature to determine the effects of global warming on the
windthrow loss of this species. Surface soil frost is expected to decrease
from 45 to 23 months per year in southern Finland and from 56
to 45 in the north. Shortening of the freezing season could be even
greater deeper in the soil. In the warmer climate, 85% of the damaging
winds would occur during the unfrozen season, as compared with 55% at the
present in southern Finland. In northern Finland, the number would be 50%,
compared with 40% today.
Guide to Publishers
Index of Abbreviations