Transcript Material for topic 6

Topic 6:
Climate change and climate
models in Colombia
Climate Change Impacts in Colombia
What the IPCC 4th Assessment Report has found:
•
Retreat of glaciers are affecting already compromised water availability for
consumption or hydropower generation [TS4.2 & 13.2.4].
•
Between 1990-2000 a 82% reduction in glaciers, showing a linear withdrawal of
the ice of 10-15 m yearly. Under the current climate trends, glaciers of the country
will disappear completely within the next 100 years [Table 13.3]
•
In the future, sea level rise, weather and climatic variability and extremes modified by
global warming are very likely to have impacts on mangroves [13.4.4].
•
SLR of 1.0 m would permanent flood 4,900 km2 of low lying coast. About 1.4
million people would be affected, 7,208,299 ha of crops and pasture will be lost
[Table 13.7].
Seminar of the excursion to Colombia – Topic 6
21 October 2009
Predictability of weather and climate
Trenberth
Seminar of the excursion to Colombia – Topic 6
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Climate Models as a tool for future projections
CAM T341- Jim Hack
Seminar of the excursion to Colombia – Topic 6
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Seminar of the excursion to Colombia – Topic 6
21 October 2009
What is behind a climate model
• 3-dimension mathematical Grid
• Based on physical laws
• Represented by equations
• Horizontal Resolution: 150-500 km
www.bom.gov.au
Seminar of the excursion to Colombia – Topic 6
21 October 2009
Future of GCM – Earth System Models
Ice Sheet
IPCC, 2001
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Auflösung GCM – Earth System Model
310km
300
IPCC AR3
1998
Global
General
Circulation
Horizontal Grid Size (Km)
250
220
220km
200
150
160km
IPCC AR4
2004 4TF
Continental
large-scale
flow
110km
100
Regional
78km
50
55km
39km
28km
11km
0
IPCC AR5
2010 500TF
local
0
L. Buja, NCAR, 2007
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GCMs for impact assessments
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Dynamical Downscaling - RCM
Emissionsszenario
www.climateprediction.net
GCM
Re-Analysis (z.B. ERA40)
• 200-500 km horizontal resolution
• GCM: Scenarios possible
• Re-Analysis: ‘perfect boundary
conditions‘
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Regional Climate Model
• 10-50 km horizontal resolution
• `time-slice‘ experiments
CTRL (e.g. 1961-1990)
SCEN (e.g. 2071-2100)
• Initial and lateral conditions
provided by GCM (scenario) or
Reanalyses (current climate)
21 October 2009
Statistical Downscaling
UC, Santander, Spain
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IPCC GCM results
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IPCC GCM results
Temperature at 2030
Averages and Extremes
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IPCC GCM results
Precipitation 2030
Averages and Extremes
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IPCC GCM web tool
Seminar of the excursion to Colombia – Topic 6
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Group 6: CC and Climate Models in Colombia
• Which large scale atmospheric circulation pattern
influence Colombia’s climate, and how?
• IPCC GCM analysis (web tool): What past climate
trends and future projections for Colombia can be
detected?
• Based on the IPCC GCM analysis: How relate your
findings to the impacts found by IPCC for Colombia
(first slide)?
Seminar of the excursion to Colombia – Topic 6
21 October 2009