Transcript Why a National Assessment? - Michigan State University

How will Climate Change Affect Weather
Patterns in the Great Lakes Region?
Peter J. Sousounis
Geography Department
Michigan State University, East Lansing, MI
www.geo.msu.edu/glra
Background Information
 Greenhouse gases make our planet habitable
 Too much of a good thing can be bad
 GCMs are our climatological crystal ball
 Recent motivation
Climate Scenarios - Temperature
Canadian Model 21st
Hadley Model 21st
+15.F
+15.F
+10.F
+10.F
+5.F
+5.F
0.
0.
-5.F
-5.F
• Both GCMs (General Circulation Models) indicate a warmer future by the end
of the century
• Canadian Model is considerably warmer than Hadley Model
Climate Scenarios - Precipitation
Hadley Model 21st
Canadian Model 21st
100%
80%
60%
40%
20%
0
-20%
-40%
-60%
-80%
- 100%
• Both GCMs (General Circulation Models) indicate increased precipitation
• Canadian Model drier than Hadley in Eastern US regions & wetter in Southwestern
US and mountainous regions
Monthly Thickness - Future Conditions
Thickness of the lower half of the atmosphere reflects surface temperature in a large scale way. A
thicker atmosphere is a warmer atmosphere.
CANADIAN
HADLEY
• Canadian Model shows significant increases in thickness throughout the year by the end of the
century
• Hadley Model shows overall smaller changes than Canadian Model
• Both Models show greater increases in fall & winter, than spring & summer
Arctic Blasts - Current Scenario
0s-10s
20s-30s
Current arctic air outbreaks cause daytime temps to be in the single digits and
teens as far south as Kentucky.
Arctic Blasts - Future Scenario
0s-10s
20s-30s
Such air masses will likely be confined to Canada by the end of this century.
Monthly Precipitation - Future Conditions
CANADIAN
HADLEY
• Canadian shows an increase of ~8% in annual precipitation by 2099. Most of the
increase occurs during January-June
• Hadley shows an increase of 12%. Most of the increase occurs during JulyDecember
Why Should Precipitation Increase…?
 More frequent storms
 Slower storms
 Stronger storms
 Moister storms
 More efficient storms
Heavy Precipitation DAYS for Detroit, Michigan
Both models suggest an increase in interannual variability
•
Canadian Model shows increases from 6 to 8 days
•
Hadley Model increases from 3 to 6 days
Heavy Precipitation AMOUNT for Detroit, Michigan
Both models suggest an increase in interannual variability
•
Canadian Model shows increases from 160 to 240 mm
•
Hadley Model shows increases from 68 to 133 mm
Precipitation - Hadley Extreme PCN Pattern
Both models show similar patterns for the current and future climate
scenarios but with lows farther to the southwest. The Canadian Model shows
increases from 40 to 47 mm…
CURRENT
FUTURE
The Hadley Model (above) shows a precipitation increase from 23 to 29 mm.
The heavier precipitation in both models will likely result from slightly more
intense lows and sharper warm fronts.
Monthly Storms - Future Climate
CANADIAN
HADLEY
Both models show a decrease in cyclones and a reduction in associated
windspeed. The Canadian Model shows a big decrease in cyclones from late
spring/ mid summer and from late fall/ mid winter. The Hadley Model shows a big
decrease in cyclones in winter and a bigger decrease in spring.
Snow Depth - Historic, Hadley & Canadian
80 inches
80
70
60
50
40
30
20
10
0
Historic
Record
Hadley Model
Canadian
Model
Snow Depth - Historic, Hadley & Canadian
80 inches
80
70
60
46 inches
50
40
30
20
10
0
Historic
Record
Hadley Model
Canadian
Model
Snow Depth - Historic, Hadley & Canadian
80 inches
80
70
60
46 inches
50
40
30
10 inches
20
10
0
Historic
Record
Hadley Model
Canadian
Model
# Snow Days - Historic, Hadley & Canadian
Historic Record:
Hadley Model:
Canadian Model:
= >1”
Snow Day
# Snow Days - Historic, Hadley & Canadian
Historic Record:
Hadley Model:
Canadian Model:
= >1”
Snow Day
# Snow Days - Historic, Hadley & Canadian
Historic Record:
Hadley Model:
Canadian Model:
= >1”
Snow Day
A SAD Story…
Unfortunately, while it may become too warm
for snow, it will still be too cold for people to
switch to other (typically summertime)
recreational activities such as camping,
golfing, and bicycling. More people may find
themselves stuck at home and there may be
more incidences of Seasonal Affective
Disorder - a SAD state of affairs indeed.
Peter Sousounis - The Future of Lake-Effect Snow: A SAD Story, Jan-Feb Acclimations:
http://www.usgcrp.gov/usgcrp/Library/nationalassessment/newsletter/2000.02/Lakefx.html
Future Winter Flow Patterns…
Both models suggest more frequent and intense El Ninos - especially the
Hadley Model…
Summary
 Climate change in the Great Lakes region will be manifested by
changes in winds and storm tracks as well as by changes in
temperature and precipitation.
 Extreme hot days will occur at least twice as frequently, extreme
precipitation events will increase in frequency and intensity. The
number of cyclones will decrease by ~15% and windspeeds will
decrease by 10%.
 Interannual variability will also likely increase.
 The magnitudes of the climate changes will likely have significant
impacts on ecosystems in the region.