Transcript Document

Iowa’s Climate 2030
Eugene S. Takle
Director, Climate Science Program
Professor of Atmospheric Science
Department of Geological and Atmospheric Sciences
Professor of Agricultural Meteorology
Department of Agronomy
Iowa State University
Ames, Iowa 50011
[email protected]
Municipal Utilities 2030
Ankeny, Iowa
8 April 2010
“I hear so many
conflicting views on
climate change,
I don’t know what or
who to believe”
Soybean producer from NE Iowa
In science, the
prevailing theory is
the one that explains
the balance of
evidence
What is the evidence?
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
NASA
http://data.giss.nasa.gov/gistemp/graphs/
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
Temperature Trends in Upper and Lower
Atmosphere
Upper
Atmosphere
(Stratosphere)
Lower
Atmosphere
(Troposphere)
“One of the clearest trends in the
United States observational record
is an increasing frequency and
intensity of heavy precipitation
events… Over the last century
there was a 50% increase in the
frequency of days with
precipitation over 101.6 mm (four
inches) in the upper midwestern
U.S.; this trend is statistically
significant “
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009:
Global Climate Change Impacts in the United States.
Cambridge University Press, 2009, 196pp.
Arctic Sea-Ice Decline
Decline in Greenland Ice Mass
Equivalent to about 5 ft of
ice over the state of Iowa
each year
Tropical Atlantic Ocean
Hurricane Power Dissipation Index (PDI)
Sea-surface temperature
V
V
V
Emanual, Kerry, 2005: Increasing destructiveness of tropical cyclones
over the past 30 years. Nature, 436, 686-688.
Ocean Heat Content
1oC rise in top 3 m of global
ocean is equivalent to a 1oC
rise in entire atmosphere
Where is this extra
heat coming from?
Possible
mechanisms:
• More solar radiation
• Less reflection from clouds
• Less reflection from Earth’s
surface
• More energy trapped and
recycled by ozone and
greenhouse gases
Earth’s Energy Balance:
Incoming solar = outgoing infrared
radiation
But rapid changes in atmosphere and
ocean temperatures and loss of land
and sea ice indicate an imbalance
?
Earth’s Energy Balance:
Incoming solar = outgoing infrared
radiation
But rapid changes in atmosphere and
ocean temperatures and loss of land
and sea ice indicate an imbalance
?
?
?
0.1
%
*Other solar cycles have periods of 22,000, 41,000, and 100,000
Forcing Factors in the Global Climate
More trapped
(recycled) heat
More cloud &
land reflection
See Arritt for details
this afternoon
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Increasing
greenhouse gases
increases heating
of the Earth
Increased Greenhouse Gases
=> Global Heating
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009.
Global Carbon Emissions (Gt)
Actual emissions are exceeding worst
case scenarios projected in 1990
Warming of the Lower
and Upper Atmosphere
Produced by Natural
and Human Causes
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009:
Global Climate Change Impacts in the United States.
Cambridge University Press, 2009, 196pp.
Warming of the Lower
and Upper Atmosphere
Produced by Natural
and Human Causes
Note that greenhouse gases
have a unique temperature
signature, with strong
warming in the upper
troposphere, cooling in the
lower stratosphere and strong
warming over the North Pole.
No other warming factors
have this signature.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009:
Global Climate Change Impacts in the United States.
Cambridge University Press, 2009, 196pp.
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Attribution studies: See
Anderson this afternoon
for applications to the
Midwest
Source: Jerry Meehl, National Center for Atmospheric Research
The balance of
evidence for the
magnitude and
distribution of
warming is explained
by increases in
atmospheric
greenhouse gases
The “Cone of Uncertainty”
Energy intensive
Balanced fuel sources
More environmentally friendly
If current emission trends
continue, global temperature rise
will exceed worst case scenarios
projected in 2007
FI =fossil intensive
IPCC Fourth Assessment Report Summary for Policy Makers
IPCC 2007
7.2oF
DecemberJanuaryFebruary
Temperature
Change
6.3oF
A1B Emission
Scenario
2080-2099
minus1980-1999
IPCC 2007
June-JulyAugust
Temperature
Change
4.5oF
5.4oF
A1B Emission
Scenario
2080-2099
minus1980-1999
June-JulyAugust
Temperature
Change
4.5oF
5.4oF
Not the direction
of current trends
A1B Emission
Scenario
2080-2099
minus1980-1999
IPCC 2007
Low confidence in model projection of summer
precipitation
IPCC 2007
IPCC 2007
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Low confidence
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Trend of increase
in occurrence of
heavy precipitation
over the 20th C is
consistent with
increasing GHG
concentrations.
Frequency of
intense
precipitation
events is likely to
increase in the
future.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009:
Global Climate Change Impacts in the United States.
Cambridge University Press, 2009, 196pp.
The planet is
committed to a
warming over the
next 50 years
regardless of
political decisions
Adaptation
Necessary
Adaptation
Necessary
Mitigation
Possible
Karl, T. R., J. M. Melillo, and T. C. Peterson,
(eds.), 2009: Global Climate Change Impacts in
the United States. Cambridge University Press,
2009, 196pp.
The planet is
committed to a
warming over the
next 50 years
regardless of
political decisions
Adaptation
Necessary
Adaptation
Necessary
Mitigation
Possible
Karl, T. R., J. M. Melillo, and T. C. Peterson,
(eds.), 2009: Global Climate Change
Impacts in the United States. Cambridge
University Press, 2009, 196pp.
Observed Summer (JJA) Daily Maximum Temperature
Changes (K), 1976-2000
Adapted from
Folland et al.
[2001]
Des Moines Airport Data
1983: 13
1988: 10
2009: 0
Des Moines Airport Data
1983: 13
1988: 10
6 days ≥ 100oF in the last 20 years
2009: 0
State-Wide Average Data
State-Wide Average Data
Totals above 40”
Cedar Rapids Data
Cedar Rapids Data
D. Herzmann, Iowa Environmental Mesonet
State-Wide Average Data
Projected Changes* for the
Climate of the Midwest
Temperature




Longer frost-free period (high)
Higher average winter temperatures (high)
Fewer extreme cold temperatures in winter (high)
Fewer extreme high temperatures in summer in short
term but more in long term (medium)
 Higher nighttime temperatures both summer and
winter (high)
 More freeze-thaw cycles (high)
 Increased temperature variability (high)
Follows trend of last 25 years and projected by models
No current trend but model suggestion or current trend but model inconclusive
*Estimated from IPCC reports
Projected Changes* for the
Climate of the Midwest
Precipitation
 More (~10%) precipitation annually (medium)
 Change in “seasonality”: Most of the increase will come in the
first half of the year (wetter springs, drier summers) (high)
 More water-logging of soils (medium)
 More variability of summer precipitation (high)
 More intense rain events and hence more runoff (high)
 Higher episodic streamflow (medium)
 Longer periods without rain (medium)
 Higher absolute humidity (high)
 Stronger storm systems (medium)
 More winter soil moisture recharge (medium)
 Snowfall increases (late winter) in short term but
decreases in the long run (medium)
Follows trend of last 25 years and projected by models
No current trend but model suggestion or current trend but model inconclusive
*Estimated from IPCC reports
Iowa Agricultural Producers’ Adaptations
to Climate Change
 Longer growing season: plant earlier, plant longer season
hybrids, harvest later
 Wetter springs: larger machinery enables planting in smaller
weather windows
 More summer precipitation: higher planting densities for
higher yields
 Wetter springs and summers: more subsurface drainage tile
is being installed, closer spacing, sloped surfaces
 Fewer extreme heat events: higher planting densities, fewer
pollination failures
 Higher humidity: more spraying for pathogens favored by
moist conditions. more problems with fall crop dry-down,
wider bean heads for faster harvest due to shorter harvest
period during the daytime.
 Drier autumns: delay harvest to take advantage of natural
dry-down conditions
Is it genetics or climate? Likely
HIGHER YIELDS!!
some of each.
Wind Power:
A New Energy
Opportunity for Iowa
54-hour Forecasts Initialized at 00UTC (6 PM CST)
Different turbulence schemes
Observations at Pomeroy, IA
Global model initialization
Midnight
Noon
Midnight
Noon
Midnight
Conceptual Model of Turbine-crop Interaction via
Mean Wind and Turbulence Fields
Speed recovery
day H2O CO2
Heat
__
night
___________________________________
Summary
 There is no scientifically defensible
explanation for atmospheric warming,
increase in ocean heat content, and loss of
ocean and land ice over the last 40 year other
than increase of anthropogenic greenhouse
gases
 Some recent climate trends in the Midwest
that have been favorable to agriculture likely
will continue in the next few years
 Climate challenges to agriculture will intensify
toward mid-century
 Iowa’s wind energy resources offer an
alternative for contributing to the nation’s
energy needs while reducing emissions of
greenhouse gases
For More Information
 National academies of science joint statement (May
2009): G8+5 Academies’ joint statement: Climate
change and the transformation of energy
technologies for a low carbon future.
[http://www.nationalacademies.org/includes/G8+5energy-climate09.pdf]
 North American Regional Climate Change
Assessment Program: http://www.narccap.ucar.edu/
 For current activities on the ISU campus, regionally
and nationally relating to climate change see the
Climate Science Initiative website:
http://climate.agron.iastate.edu/
 Contact me directly: [email protected]