climate change and agriculture in the united states · climate change and agriculture in the united...

CLIMATE CHANGE AND AGRICULTURE IN THE UNITED STATES

Jerry L. Hatfield USDA-ARS

Resilient Agriculture 2014

This research is part of a regional collaborative project supported by the USDA-NIFA, Award No. 2011-68002-30190: Cropping Systems Coordinated Agricultural Project: Climate Change, Mitigation, and Adaptation in Corn-based Cropping Systems

IMPACTS OF CLIMATE CHANGE ON AGRICULTURAL PRODUCTIVITY CAN BE OFFSET BY: Utilizing improved genetics Reducing soil erosion and increasing infiltration Improved nutrient management Better weather forecasts Changing cropping systems

CLIMATE VS WEATHER

Climate determines where we grow a crop Weather determines how much we produce

CROP PRODUCTION

US GRAIN PRODUCTION

US Wheat Production

Year1950 1960 1970 1980 1990 2000 2010 2020

Yiel

d (b

u ac

re-1

)

10

15

20

25

30

35

40

45

50

US Soybean Production

Year1950 1960 1970 1980 1990 2000 2010 2020

Yiel

d (b

u ac

re-1

)

15

20

25

30

35

40

45

50

US Corn Production

Year1950 1960 1970 1980 1990 2000 2010 2020

Yiel

d (b

u ac

re-1

)

20

40

60

80

100

120

140

160

180

CLIMATE FACTORS

Inputs Temperature Precipitation Solar radiation Carbon dioxide

Direct Growth Phenology Yield

Indirect Insects Diseases Weeds

Soil is the underlying factor as a resource for nutrients and water

CARBON DIOXIDE INCREASES

TEMPERATURE CHANGE BY DECADE

OBSERVED U.S. TEMPERATURE CHANGE

OBSERVED INCREASES IN FROST-FREE SEASON

PROJECTED TEMPERATURE CHANGE

OBSERVED U.S. TRENDS IN HEAVY PRECIPITATION

OBSERVED CHANGE IN VERY HEAVY PRECIPITATION

INCREASING HEAVY DOWNPOURS IN IOWA

SPRING PRECIPITATION (AMES)

Ames Spring Precipitation

Year1880 1900 1920 1940 1960 1980 2000 2020

Pre

cipi

tatio

n (in

ches

)

0

2

4

6

8

10

12

14

16

18

20

22

Spring Precip (March-May)Mean Spring Precip

The increase in spring precipitation has decreased the number of workable field days in April through mid-May across Iowa by 3.7 in 1995 to 2010 compared to 1979-1994

EROSION: HOW MUCH IS TOLERABLE

THE WIND BLOWS TOO

Wet Spring Hot Summer

Wet Spring Cool Summer

Dry Spring Cool Summer

Dry Spring Hot Summer

CLIMATE PROJECTION: WETTER SPRING, HOTTER SUMMER Iowa climate

projection is average May-June rainfall and July-August temperature using 9 downscaled climate scenarios, spanning 3 GCMs and 3 emissions scenarios.

Training period for downscale method is 1960-1999.

Data Source: Stoner et al. (2013)

QUESTION

How is agriculture going to cope with the increasing variability in the within season weather and trends toward a warmer climate with shifting seasonality in precipitation?

PROJECTED PRECIPITATION CHANGE BY SEASON

TEMPERATURE CHANGES

NIGHTTIME TEMPERATURES

TEMPERATURE EFFECTS ON EVAPORATION

Air Temperature (C)0 10 20 30 40 50

Sat

urat

ion

Vap

or P

ress

ure

(kP

a)

0

2

4

6

8

10

12

14

e* = 0.61121 exp(17.502Ta/Ta + 240.97)

𝐸𝐸𝐸𝐸 = 𝜌𝜌𝑐𝑐𝑝𝑝(𝐸𝐸0 − 𝐸𝐸𝑠𝑠)

𝑟𝑟𝑎𝑎+ 𝜌𝜌𝑐𝑐𝑝𝑝[𝑒𝑒𝑠𝑠 𝐸𝐸0 − 𝑒𝑒𝑎𝑎]𝛾𝛾(1 + 𝑟𝑟𝑠𝑠 𝑟𝑟𝑎𝑎� )𝑟𝑟𝑎𝑎

WHAT DOES ALL OF THIS MEAN TO THE PRODUCER?

Begin to consider all aspects of the crop production system as an integrated set of components

Utilize the following examples as guides

CROP YIELD VARIATION

SOIL WATER USE RATES

Corn Water Use 2000

Day of Year100 120 140 160 180 200 220 240 260 280

Wat

er U

se (m

m)

0

100

200

300

400

500

600

Clarion Spring N (100 kg/ha) Webster Spring N (100 kg/ha)Clarion Fall N (200 kg/ha)Webster Fall N (200 kg/ha)

GOOD SOILS = GOOD YIELDS

Mean NCCPI

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Cou

nty

Yiel

d (g

m-2

)

180

200

220

240

260

280

300

320

340

KentuckyIowaNebraska

Kentucky(Double crop)Y = 131.187 + 187.458X. r2 = 0.72***

Soybean yields across Iowa, Kentucky, and Nebraska

NCCPI-AG

0.4 0.6 0.8 1.0

Mea

n C

ount

y Yi

eld

(g m

-2)

500

600

700

800

900

1000

KentuckyIowa

Y = 436.096 + 478.149X, r2 = 0.58***

MAIZE COUNTY YIELDS

TEMPERATURE RESPONSES

TEMPERATURE EFFECTS ON CORN PHENOLOGY

Corn Hybrid RX730

Days after Planting0 20 40 60 80 100 120

Tota

l Col

lars

0

5

10

15

20

25

Normal TemperaturesWarm Temperatures

Corn Hybrid DK 61-72


Tota

l Col

lars

0

5

10

15

20

25


Corn Hybrid XL45A


Tota

l Col

lars

0

5

10

15

20

25


Rhizotron study with warm chamber 4C warmer than normal chamber with simulation of Ames IA temperature patterns.

0 116 bu/A 34 206 bu/A 34 218 bu/A

IMPACT OF WARM NIGHTS ON CORN AND SOYBEAN PRODUCTIVITY

Corn and Soybean Production Fields

Average Minimum Temperature (C)8 10 12 14 16 18 20 22 24 26

Net

Car

bon

Flux

(mg

m-2

s-1

)

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

Corn Soybean

CROP YIELDS DECLINE UNDER HIGHER TEMPERATURES

APPLICATION OF THESE RESULTS

Producers will not deal with a single climate factor, exposed to all factors, temperature, precipitation, carbon dioxide, solar radiation

What is in the producers control? Concept that we must begin the process of

understanding agriculture systems as the interactions of genetics, environment and management.

CONCEPT OF G X E X M

Genetics

Environment Management

Ames Minimum Temperature - Summer

Year 1880 1900 1920 1940 1960 1980 2000 2020

Tem

pera

ture

(F)

54

56

58

60

62

64

66

Summer Temp (June-Aug)Mean Summer Temp

FOUNDATION OF CLIMATE RESILIENCE FOR AGRICULTURE IS BASED ON:

Soil and soil water availability Yield variation within fields and among years is

due to soil water availability which exaggerates the temperature effect.

Soil water increases the ability of the crop to utilize nutrients

SOIL EROSION

Organic Matter (%)0 1 2 3 4 5 6 7

Avai

labl

e W

ater

Con

tent

(%)

0

5

10

15

20

25

30

35

Data Points Sand, AWC = 3.8 + 2.2 OMSilt Loam, AWC = 9.2 + 3.7 OMSilty clay loam, AWC = 6.3 + 2.8 OM

Degrading the soil resource decreases the water holding capacity Hudson, 1994

Organic Matter Effects on Available Water Capacity

Silt loam

OM increase from 1% to 4.5% AWC doubles!

5.7% 22.9% (% by Vol.)

Data from Soil Survey Investigation Reports (surface horizons only) - Sands: FL (n = 20) - Silt loams: IA, WI, MN, KS (n = 18) - Silty clay loams: IA, WI, MN, KS (n = 21)

Sands AWC = 3.8 + 2.2 (OM) r2 = 0.79 Silt loams AWC = 9.2 + 3.7(OM) r2 = 0.58 Silty clay loams AWC = 6.3 + 2.8 (OM) r2 = 0.76

Hudson, B. D. 1994. Soil organic matter and available water capacity. J. Soil Water Conserv. 49(2):189-194.

SENESCENCE INDEX 2008 Continuous Corn

Sum (1-PSRI * Daily PAR)

1.26e+6 1.28e+6 1.30e+6 1.32e+6 1.34e+6 1.36e+6

Yie

ld (k

g ha

-1)

2000

4000

6000

8000

10000

12000

14000

Data points Yield = -101098 + 0.084 * Sum R2 = 0.87

2009 Continuous Corn


1.02e+6 1.03e+6 1.04e+6 1.05e+6 1.06e+6

Yie

ld (k

g ha

-1)

2000

4000

6000

8000

10000

12000

14000


2010 Continuous Corn


7.9e+5 8.0e+5 8.1e+5 8.2e+5 8.3e+5 8.4e+5 8.5e+5

Yie

ld (k

g ha

-1)

2000

4000

6000

8000

10000

12000

14000


The longer we can maintain green leaf area during the grain-filling period the higher the yield

CONSERVATION AGRICULTURE BENEFITS

Short-term Reduce soil water

evaporation Increase infiltration of

rainfall or irrigation events

Reduce the overall of evapotranspiration rate if plants are grown in standing stubble

Long-term Increase the soil water

holding capacity through improved organic matter content

Increase water availability to the crop

Increase rooting depth

CLIMATE RESILIENCE

Will have to rely on capturing, storing, and making available maximum amount of soil water to the crop during the growing season

Implement cropping system which increase the organic matter content of the soil and reduce erosion under the shifting precipitation patterns

CLIMATE FACTORS

Inputs Temperature Precipitation Solar radiation Carbon dioxide

Direct Growth Phenology Yield

Indirect Insects Diseases Weeds

Soil is the underlying factor as a resource for nutrients and water

GOOD NEWS

You can’t control the weather but you can manage the soil and management inputs to increase climate resilience

Aggressive soil management to improve organic matter (soil water storage and infiltration rates) will pay dividends in improved yield stability and water and nutrient use efficiency

IMPROVED SOIL MANAGEMENT PRACTICES COULD BE IMPLEMENTED ON MY FARM BY: Decreasing tillage Increasing the retention of crop residue Adding cover crops to provide for more

ground cover and residue Changing a crop rotation to diversify crops I am not convinced any of these can work on

my farm

climate change and agriculture in the united states · climate change and agriculture in the united...

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