Weather and climate have both short-term and long-term impacts on livestock development and management. This talk will focus on longer-term trends in climate and drought over time across the United States and the impacts of changes in these factors on animal agriculture. We will start by examining the trends in temperature and precipitation that have occurred over different regions of the US over the past century and how they have varied from one area to another. Then we will look at how future climate is predicted and problems in making useful predictions. We will follow that by looking at some of the most reliable predictions of future climate and discuss the potential impacts on livestock health, forage and feed supply, and farm management practices and the importance of resilience in farm practices. We will conclude by identifying both the challenges and the opportunities for future livestock producers in a changing climate. http://www.extension.org/pages/67615/impacts-of-a-changing-cimate-on-animal-agriculture

1. 1
A n i m a l A g r i c u l t u r e & C l i m a t e C h a n g e
Developing National Extension Capacity to Address Issues Related to Animal Agriculture and Climate Change
Livestock And Poultry
Environmental Learning CenterThis project was supported by Agricultural and Food Research Initiative Competitive Grant
No. 2011-67003-30206 from the USDA National Institute of Food and Agriculture.
Impacts of a Changing Climate on
Animal Agriculture
Pam Knox, University of Georgia
Agricultural Climatologist
pknox@uga.edu

2. Outline
1. Trends in temperature and precipitation across the US
2. Predicting future climate: possibilities and problems
3. Most reliable predictions of future climate
4. Impacts of future climate on livestock and farm
management
5. Challenges and opportunities for livestock farmers in the
future

3. What is Climate?

4. Review of Present Climate Trends:

5. Regional Temperature Trends

6. Review of Present Climate Trends:
US Temperature
http://www.ncdc.noaa.gov/cag/time-series/us
WA
CO
TX
NY
GA

7. Review of Present Climate Trends:
Global Temperature

8. Review of Present Climate Trends:

9. Review of Present Climate Trends:
Precipitation
WA
CO
NY
GA
TX

10. Seasonal Precipitation Trends

11. Review of Present Climate Trends:
Global Precipitation

12. How to Predict Future Climate
• Continuation of present trends
• Oscillations
• General circulation model (GCM) uses
energy balance to calculate future climate

13. How to Predict Climate
You can predict climate by predicting trends, but that depends
on things continuing the same way they have in the past. Not
always a good assumption!
Instead, climatologists use climate models to simulate the
future climate based on physics and predictions of future CO2
and other emissions.

14. Climate 101: Energy Balance
Energy in – Energy out =
Change in temperature
Energy in > Energy out Increasing temperature
Energy in > Energy out Decreasing temperature

15. Climate 101: Energy Balance

16. Climate Models

17. Increasing Model Complexity

18. Global Climate Models
A model has to have a way to account for all the
process in the atmosphere-ocean system To use a
computer, the information has to be divided into
individual boxes or grids which are all connected.

19. Problems with Models
• Coarse resolution leaves out
mountains, Great Lakes, alters
local conditions like coastlines
• Simplification processes make
rainfall less believable since
most of it happens in sub-
gridscale processes like
thunderstorms
• They are not very good at
predicting current climate,
making them less believable
• No El Niño, hurricanes

20. Weather vs. Climate Models
Weather models are designed
to predict detailed hourly
weather information for up to 7
days across a continent.
Emphasis: short term,
individual storm evolution
Climate models are designed to
predict multi-year climate
conditions across the entire globe.
Emphasis: long-term, seasonal to
multi-year average climate
conditions

21. Changes in Atmospheric Composition

22. Models can separate out CO2 Effects
Models can be used to separate out the effects of individual factors to see what
effect each factor has on the temperature trend.

23. Scenario Modeling
Modelers use scenarios of
various projections of changing
CO2, changing energy efficiency,
etc. to produce a series of graphs
giving a range of expected
outcomes.
Observations don’t always agree with
predictions. So which is right?

24. Predicted Trends in Temperature
Across the United States, temperatures are predicted to increase
over the next 100 years, but the amount of warming predicted
depends on the particular model used.
http://www.usgcrp.gov/usgcrp/nacc/education/

25. http://www.usgcrp.gov/usgcrp/nacc/education/default.htm

26. Predicted Trends in Precipitation
http://www.usgcrp.gov/usgcrp/nacc/education/
Precipitation across the US is harder for the models to predict, and
some models show increased precipitation while others show
drying or no trend. Some datasets indicate that rainfall has become
more intense with longer dry spells in between.

27. http://www.usgcrp.gov/usgcrp/nacc/education/default.htm

28. Projected Change in Precipitation over
next 100 Years

29. Impacts of Changing Climate
on Livestock and Poultry
• Warmer temperatures would increase growing degree days for
forage and crops but also weeds and insect pests and diseases.
• Warmer temperatures, both daytime and nighttime, would
increase heat stress on livestock and increase the need for and the
costs of cooling.
• Warmer temperatures will decrease heating costs in winter.

30. Impacts of Changing Climate
on Livestock and Poultry
• Warmer temperatures will increase evaporation from farm ponds,
lakes and reservoirs, which could affect water availability and
affect the ability to irrigate.
• Power generation from coal-burning and nuclear plants as well as
hydropower from dams all depend on availability of water and
power prices could be negatively affected by warmer
temperatures.

31. Impacts of Changing Climate
on Livestock and Poultry
• Uncertainty of rainfall predictions makes it hard to determine
what to expect in the future, especially since there is already a
lot of natural variability in rainfall patterns by location and
season.
• Higher intensity rainfall will increase erosion and runoff from
farm fields and could increase localized flash flooding in
storms.

32. Impacts of Changing Climate
on Livestock and Poultry
• Longer dry spells, coupled with warmer temperatures,
will increase the likelihood of drought and will reduce
average stream flows.
• Seasonal changes in precipitation could affect
pollination and harvesting of cereal crops.

33. What does the Future Hold?
Challenges
• Warmer temperatures
increase diseases and pests
• More stress on livestock
• More potential for drought
• More extremes
• Market uncertainty
• Economic costs of becoming
resilient (for example,
irrigation or power sources)
• Changing tastes and
demographics
Opportunities
• Population growth means
potential for market growth
• Parts of the US will see
increased growing season
and more rainfall
• Other parts of the world will
also undergo climate change,
leading to expanded markets
• Smart management can
improve budget while also
taking advantage of market
incentives

34. For More Information
Or contact me at:
Pam Knox
706-310-3467
pknox@uga.edu

35. Livestock And Poultry
Environmental Learning Center
For a full list of references cited
in this presentation, please visit:
www.animalagclimatechange.org
This project was supported by Agricultural and Food Research Initiative Competitive Grant
No. 2011-67003-30206 from the USDA National Institute of Food and Agriculture.
Developing National Extension Capacity to Address Issues Related to Animal Agriculture and Climate Change
A n i m a l A g r i c u l t u r e & C l i m a t e C h a n g e
Developing National Extension Capacity to Address Issues Related to Animal Agriculture and Climate Change