HR: 0800h
AN: GC41A-0110 [Abstracts]
TI: Assessment of 21st Century Climate Change Projections in the Tropical Andes
AU: * Urrutia, R B
EM: rurrutia@geo.umass.edu
AF: Climate System Research Center, Department of Geosciences,University of
Massachusetts Amherst, Morrill Science Center
611 North Pleasant Street, Amherst, MA 01003-9297, United States
AU: Vuille, M
EM: mathias@geo.umass.edu
AF: Climate System Research Center, Department of Geosciences,University of
Massachusetts Amherst, Morrill Science Center
611 North Pleasant Street, Amherst, MA 01003-9297, United States
AB:
The tropical Andes are one of the regions of the globe where climate change has been most evident. This is
consistent with the notion that tropical high-elevation mountains extending into the mid-troposphere will be more
affected by warming. One of the main impacts of this warming is the rapid retreat of glaciers; a process that could
have severe consequences, affecting the availability of water for human consumption, irrigation, mining, and
hydroelectric power production.
This study presents some results related to the most important changes in climate that might be expected in the
tropical Andes, at the end of the 21st century. Results are provided by the comparison of two Regional
Climate Model (RCM) simulations based on the Hadley Center Regional Climate Modeling System, PRECIS. A
medium-high CO2 emission scenario simulation for the period 2071-2100 (Intergovernmental Panel on
Climate Change, IPCC-SRES scenario A2) is compared to a base-line mean climate state simulation for the
1961-1990 period. In addition, some results using a low-medium CO2 emission scenario (IPCC-SRES
scenario B2) are also presented for comparison.
Preliminary results show a generalized warming over the region with values reaching up to approximately
7° C in some places in the Andes in the A2 scenario. Precipitation presents a mixed pattern of increases
and decreases across the region, and a decrease in relative humidity is expected for most of the highlands at the
end of the century. Both scenarios (B2 and A2) show an increased warming of the free troposphere at higher
altitudes (up to 200 hPa).
The obtained results reveal that anthropogenic climate change, as predicted with the A2 scenario, may constitute
a serious threat to the survival of tropical glaciers along the Andes Cordillera.
DE: 1637 Regional climate change
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting