Transcript Des Moines Airport Data - Climate Science Program

Climate Change and Conservation
Eugene S. Takle
Director, Climate Science Initiative
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]
Iowa Water Conference
Ames, Iowa
8-9 March 2010
Outline
Causes of climate change
Global and regional changes in
climate and projected future
changes
Past trends in Iowa and producer
adjustments to climate change
My speculation on future climate
trends of importance to agriculture
and conservation
NASA
http://data.giss.nasa.gov/gistemp/graphs/
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
“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.
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
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
Source: Jerry Meehl, National Center for Atmospheric Research
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]
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
“Warming
Hole”:
Simulations of
changes in daily
maximum
summertime
temperatures
between 1990s
and 2040s
DTmax (JJA) ˚C
Pan, Z., R. W. Arritt, E. S. Takle, W. J. Gutowski, Jr., C. J. Anderson, and M. Segal,2004: Altered hydrologic feedback in a warming
climate introduces a “warming hole”. Geophys. Res. Lett.31, L17109, doi:10.1029/2004GL020528.
State-Wide Average Data
State-Wide Average Data
Totals above 40”
Cedar Rapids Data
Cedar Rapids Data
Relationship of Streamflow
to Precipitation in Current
and Future Climates
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
Projected Changes* for the
Climate of the Midwest
Other






Reduced wind speeds (high)
Reduced solar radiation (medium)
Increased tropospheric ozone (high)
Accelerated loss of soil carbon (high)
Phenological stages are shortened (high)
Weeds grow more rapidly under elevated atmospheric
CO2 (high)
 Weeds migrate northward and are less sensitive to
herbicides (high)
 Plants have increased water used efficiency (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 and CCSP 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.
Will These Agriculturally Favorable Midwest
Climate Trends Continue?
Caution: These are my speculations!!
 In the short-term (next 5-10 years) climatic conditions will
be dominated by natural variability from base conditions of
the past 20 years (not long-term averages)
 If we continue to have high spring and summer rainfall and
soil moisture, we likely will continue to have lower chances
of extended periods of extreme heat
 If we continue to have high spring and summer rainfall and
soil moisture, we likely will continue to have pathogens
favored by high humidities
 In the longer term (>50 years), hot summers, milder
winters, and higher variability of precipitation will become
more dominant
 Failure to limit global carbon emissions will accelerate trends
toward less favorable agricultural climate for Iowa
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 and conservation
interests will intensify toward mid-century
 Global and regional climate models have much to
offer for understanding future Midwest agricultureclimate and conservation-climate interactions
 Agriculturists and conservationists needs future
climate information at regional scales.
For More Information
 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]