1. Climate Change and Impact on Water Resource Planning
Eugene S. Takle
Certified Consulting Meteorologist
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
ASCE Environmental & Water Resources Conference
Ames, Iowa
25 March 2010

2. Outline Iowa precipitation trends of the 20th Century
Scientific basis for future climate change
Projected future global and regional changes in climate
Impacts of climate change on water resources management

3. Observed Trends in Iowa Precipitation

4. State-Wide Average Data

5. State-Wide Average Data
37.5”
31.5”
19% increase

6. State-Wide Average Data
Totals above 40”
8 years
2 years

7. State-Wide Average Data

9. Cedar Rapids Data
28.0”
32% increase
37.0”

10. Cedar Rapids Data
51% increase
11.8”
7.8”

11. Cedar Rapids Data
34% increase
20.2”
26.8”

12. “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 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.

13. Cedar Rapids Data
57% increase
6.6 days
4.2 days

14. Years having more than 8 days
Cedar Rapids Data
Years having more than 8 days 11 2
57% increase
6.6 days
4.2 days

15. State-Wide Average Data

16. D. Herzmann, Iowa Environmental Mesonet

17. 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
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.

18. Great Flood of 1993 in the US Midwest:
A New “Great Lake”
Historical Data indicate this should happen about once every 500 years
Lakshmi, V., and K. Schaaf, 2001: Analysis of the 1993 Midwestern flood using satellite and ground data. IEEE Trans. Geosci & Remote Sens., 39,

20. Projected Future Trends in Iowa Precipitation

21. “The future isn’t what it used to be”
Yogi Berra

22. NASA

23. Global Mean Surface Temperature

24. Karl, T. R. , J. M. Melillo, and T. C. Peterson, (eds
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009.

26. Global Carbon Emissions (Gt)
Actual emissions are exceeding worst case scenarios projected in 1990

27. More environmentally friendly
Energy intensive
Balanced fuel sources
More environmentally friendly
If current emission trends continue, global temperature rise will exceed worst case scenarios projected in 2007
Consider A1B
FI =fossil intensive
IPCC Fourth Assessment Report Summary for Policy Makers

28. Source: Jerry Meehl, National Center for Atmospheric Research
From Jerry Meehl
This slide shows the time evolution of globally averaged surface air
temperature from multiple ensemble simulations of 20th century climate
from the NCAR Parallel Climate Model (PCM) compared to observations.
The simulations start in the late 19th century, and continue to the year
The temperature scale at left is in degrees Centigrade, and
temperature anomalies are calculated relative to a reference period
averaged from 1890 to The black line shows the observed data, or
the actual, recorded
globally averaged surface air temperatures from the past century. The
blue and red lines are the average of four simulations each from the
computer model. The pink and light blue shaded areas depict the range
of the four simulations for each experiment, giving an idea of the
uncertainty of a given realization of 20th century climate from the
climate model. The blue line shows the average from the four member
ensemble of the simulated time evolution of globally average surface air
temperature when only "natural" influences (solar variability and
volcanic eruptions) are included in the model. Therefore, the blue
line represents what the model says global average temperatures would
have been if there had been no human influences. The red line shows the
average of the four member ensemble experiment when natural forcings AND
anthropogenic influences (greenhouse gases including carbon dioxide,
sulfate aerosols from air pollution, and ozone changes) are included in
the model. Note that this model can reproduce the actual, observed data
very well only if the combined effects of natural and anthropogenic
factors are included. The conclusion that can be drawn is that
naturally occuring influences on climate contributed to most of the
warming that occurred before WWII, but that the large observed
temperature increases since the 1970s can only be simulated in the model
if anthropogenic factors are included.
This confirms the conclusion of the IPCC Third Assessment Report that
most of the warming we have observed in the latter part of the 20th
century has been due to human influences.
Source: Jerry Meehl, National Center for Atmospheric Research

29. IPCC 2007

30. December-January-February Temperature Change
7.2oF
6.3oF
A1B Emission Scenario
minus

31. IPCC 2007

32. June-July-August Temperature Change
4.5oF
A1B Emission Scenario
minus
5.4oF

33. June-July-August Temperature Change
4.5oF
A1B Emission Scenario
minus
5.4oF
Not the direction of current trends

34. IPCC 2007

35. Low confidence in model projection of summer precipitation
IPCC 2007

36. IPCC 2007

37. Karl, T. R. , J. M. Melillo, and T. C. Peterson, (eds
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.

38. Karl, T. R. , J. M. Melillo, and T. C. Peterson, (eds
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.

39. 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.

40. 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.

41. The planet is committed to a warming over the next 50 years regardless of political decisions
Necessary
Adaptation
Necessary
Adaptation
Possible
Mitigation
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.

42. The planet is committed to a warming over the next 50 years regardless of political decisions
Necessary
Adaptation
Necessary
Adaptation
Possible
Mitigation
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.

43. Relationship of Streamflow to Precipitation in Current and Future Climates

44. 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

45. 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

46. Use of Regional Climate Modeling for Design and Decision-Making: North American Regional Climate Change Assessment Program

47. Global models lack regional detail
North America coastlines and terrain at typical global climate model resolution used for the IPCC 3rd and 4th Assessment Reports.
Hadley Centre AOGCM (HadCM3), 2.5˚ (lat) x 3.75˚ (lon), ~ 280 km
North America at 50 km grid spacing

48. NARCCAP Plan A2 Emissions Scenario GFDL CCSM HADAM3 CGCM3 MM5 RegCM3
link to EU
programs
CGCM3
current
future
Provide boundary conditions
MM5
Iowa State/
PNNL
RegCM3
UC Santa Cruz
ICTP
CRCM
Quebec,
Ouranos
HADRM3
Hadley Centre
RSM
Scripps
WRF
NCAR/
Note: AGCM time slices to be included, too. Initial phase involves driving RCMs with reanalysis output.
Reanalyzed climate ,

49. ISU Climate Science Initiative is now running four models
NARCCAP Plan
A2 Emissions Scenario
GFDL
CCSM
HADAM3
link to EU
programs
CGCM3
current
future
Provide boundary conditions
MM5
Iowa State/
PNNL
RegCM3
UC Santa Cruz
ICTP
CRCM
Quebec,
Ouranos
HADRM3
Hadley Centre
RSM
Scripps
WRF
NCAR/
ISU Climate Science Initiative
is now running four models
Note: AGCM time slices to be included, too. Initial phase involves driving RCMs with reanalysis output.
Reanalyzed climate ,

50. Iowa State University Climate Science Initiative
ISU/CSI is the only organization in the world running four different regional climate models for science, impacts and adaptation
Climate change impacts and adaptation
Streamflow in the UMRB
Subsurface tile drainage flow
Pavement performance
Building design standards
Soil carbon
Crop growth
or Google ISU CSI

51. Iowa Environmental Mesonet
Collects over 400,000 observations per day
Serves out data to thousands of users each day
Receives over 10,000,000 web hits per day

52. 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 years other than increase of anthropogenic greenhouse gases
Climate challenges to water resource management are most evident in extreme events
Changes of extremes are more evident than changes in means
Global and regional climate models have much to offer for understanding future Midwest water resource management adaptation strategies
The Iowa Environmental Mesonet provides a wealth of environmental data relative to water resource management

53. For More Information
North American Regional Climate Change Assessment Program:
For current activities on the ISU campus, regionally and nationally relating to climate change see the Climate Science Initiative website:
Contact me directly:
Contact Chris Anderson, Assistant Director of the Climate Science Initiative,