Climate Change in Ann Arbor Daniel Brown, Research Associate, GLISA
What does GLISA do?
• GLISA is an information network hub for integrated climate science
• Connects practitioners and scientists
glisa.msu.edu
Global Trends and Regional Trends
Global Trends are more certain than regional trends. Natural variability plays a larger role at the regional scale. Local changes in land use can often alter the severity of climate change impacts.
Observed and Projected Global Temperature
3.2°F
NASA, based on IPCC
6.5°F
3.2°F
Adaptation timeframe
Observed Michigan Temperature
Changes in Average Temperature (°F)
from 1951-1980 to 1981-2010
Annual 0.9
Winter 1.9
Spring 1.1
Summer 0.5
Fall -0.1
Southeast Michigan Temperature
Changes in Mean Temperature (°F)
from 1951-1980 to 1981-2010
Annual 0.6
Winter 1.4
Spring 1.0
Summer 0.3
Fall -0.1
Observed Ann Arbor Temperature
Changes in Mean Temperature (°F)
from 1951-1980 to 1981-2010
Annual 0.3
Winter 1.0
Spring 0.4
Summer 0.0
Fall -0.3
The Great Lakes are Warming
• Lake Superior is warming twice as fast as nearby air.
• Winter ice cover is decreasing.
• Lake Superior could have little to no open-lake ice cover during a typical winter within the next 30 years.
NASA
Average Great Lakes ice coverage declined 71% percent from 1973 to 2010
AMS, 2011
Austin and Colman, 2007
Future Midwest Temperature
~12°F ~9°F
~5°F ~6°F
High Emissions Scenario
Low Emissions Scenario
Modified from Hayhoe et al, 2010
More Projected Hot Days
Increase in Days > 95°F
Increase in Consecutive Days
> 95°F
2041-2070
Kunkel (2011)
Plant Hardiness Zones
-30 to -20 ºF
-40 to -30 ºF
-20 to -10 ºF
1990
Average Extreme Minimum Temperatures
-20 to -10 ºF
-5 to -10 ºF
-30 to -20 ºF
-40 to -30 ºF
2006
Longer Midwestern Growing Season
Earlier last winter frost in spring
Date of first winter frost is
often unchanged
Growing season longer by
~1-2 weeks
140
150
160
170
180
190
1895 1910 1925 1940 1955 1970 1985 2000
Leng
th o
f Gro
win
g Se
ason
(day
s)
Based on data from the National Climatic Data Center for the cooperative observer network and updated from Kunkel et al. (2004)
Shorter Winters Across the Region
Earlier last winter frost in spring
Later first winter frost in autumn
Future growing season longer by
~1-2 months Wubbles & Hayhoe (2004)
A Migrating Climate
The climate future generations experience will be fundamentally
different than the climate today.
By the end of this century, Michigan summers will feel more like current summers in Arkansas.
Courtesy UCS 2009, original work by Hayhoe et al.
Southeast Michigan Precipitation
Changes in Total Precipitation (%)
from 1951-1980 to 1981-2010
Annual 11.9
Winter 12.7
Spring 2.6
Summer 5.3
Fall 28.3
Observed Ann Arbor Precipitation
Changes in Total Precipitation (%)
from 1951-1980 to 1981-2010
Annual 25.0
Winter 16.5
Spring 7.0
Summer 7.4
Fall 16.3
• Shorter winters have lead to more precipitation falling as rain instead of snow.
• Warmer surface temperatures have reduced snow accumulation.
• More lake effect precipitation events have increased snowfall in some areas.
Changing Winter Precipitation
Photo credits: Umich.edu, NASA, weather.com
Observed Snowfall
Snowfall has generally increased across the Northern Midwest, remained stable in the central latitudes, and has decreased in the southern areas.
More here
Less here
1961-1990 Average 1981-2010 Average
Observed Extreme Precipitation
The Intensity of the heaviest 1% of precipitation events increased by 31% in the Midwest and by 67% in the Northeast
from 1958 to 2007.
Ann Arbor: 42% Increase in the number of 1%
heaviest precipitation events
1981-2010 total compared to 1951-1980
Observed Extreme Precipitation
(Pryor et al., 2009)
The frequency of the heaviest 7-day precipitation events has increased.
The 10 wettest days in a year are delivering more precipitation.
Projected Precipitation
Kunkel (2011)
2041-2070 vs. 1971-2000
Winter +5 to 20%
Spring +0 to 20%
Fall +0 to 20%
Summer +10 to -10%
Annual +5 to 15%
Key Climate Changes for A2
• Warmer average temperatures
• Warmer low and nighttime temperatures
• More potential for extreme heat and drought
• Shorter winters
• More total precipitation
• More severe precipitation events
Tourism, Recreation, and Sense of Place
As the seasonality of temperature and precipitation changes. Economic, cultural, and natural systems will be forced to adapt.
Agriculture and Food Networks
• Increasing extreme events may challenge regional food networks.
• Some crops may benefit in the near future from more CO2 and longer growing seasons until negated by warmer temperatures.
• Perennial crops will be more vulnerable to the pace of climate change.
Heat and Health
Observed Change in Number of Harmful Heat Waves The number of heat waves that
pose risks to human health have increased in most major Midwestern cities. Increasing overnight, minimum temperatures have increased at a faster rate, limiting relief during hot periods.
UCS Heat in the Heartland, 2012
Potential Transportation Impacts
Freeze-thaw Expansion buckling
Flood Damage, washouts Jane-Finch.com
Freeze-thaw damage, near Marquette, MI Expansion buckling near Marshall, MI, 2011
Flooding and Stormwater
Observed increases in total precipitation and more frequent intense storms are already impacting the area.
Solutions
Permeable pavement • Reduces runoff • Reduces erosion
• Reduces risk to water quality
Urban tree canopies • Save energy: $50000/year • Stormwater: $50000/year • Scrub greenhouse gases
from the atmosphere
Ann Arbor is a flagship city for climate adaptation