International Ricardian Studies

Marginal impacts of Temperature and Precipitation

African Crop Study

• No land value

• No wages for own labor

• No reliable county data

• Had to collect new data

• Sampled farmers in 11 countries

• Focused on net revenue per hectare

Country Dryland Irrigated Total

Burkina Faso 990 41 1031

Cameroon 646 105 751

Egypt 0 802 802

Ethiopia 874 66 940

Ghana 849 29 878

Kenya 675 79 754

Niger 849 48 897

Senegal 1037 31 1068

South Africa 199 87 286

Zambia 956 14 970

Zimbabwe 597 90 687

Total 7672 1392 9064

Variable All Farms Dryland Irrigated

Winter temperature -173.6** -106.7 -93.5

Winter temperature squared 6.1** 3.9* 4.9

Spring temperature 115.1 -82.8 58.7

Spring temperature squared -5.0** -0.3 -4.1

Summer temperature 173.9** 198.6** 827.5**

Summer temperature squared -1.9 -3.2* -13.1*

Fall temperature -98.1 -92.4 -824.2*

Fall temperature squared 1.1 1.5 15.3*

Winter precipitation -2.9* -1.9 5.8

Winter precipitation squared 0.0** 0.00 0.00

Spring precipitation 3.5* 3.6** -10.6

Spring precipitation squared -0.001 -0.011* 0.091*

Summer precipitation 3.4** 1.9* 21.4**

Summer precipitation squared -0.012** -0.005 -0.086**

Fall precipitation -0.5 -0.6 -14.7**

Fall precipitation squared 0.0055* 0.0053* 0.0586**

*

Mean Flow 9.4** -5.4 8.8**

Farm area -0.1** -0.3** -0.0**

Farm area squared 0.0* 0.0** 0.0*

Elevation 0.035 -0.0009 0.229

Log(household size) 22.9 10.1 62.4

Irrigate(1/0) 237.5**

Electricity (1/0) 66.6** 47.7** 233.2*

West Africa Dummy 136** 208** -285

North Africa Dummy 457** 675*

East Africa Dummy -186** -154** -361

Heavy Machinery Dummy 51.8** 55.5** -60.8

Animal Power Dummy 10.4 49.3** -185.5**

Constant -388 1081 -549

N 8459 7238 1221

R2 0.4 0.2 0.3

Marginal Impact Africa Regression

Irrigated Regression

Dryland Regression

Temperature -28.3**(-1.3)

33.6(0.5)

-23.0**(-1.6)

Precipitation 2.65**(0.36)

2.08(0.06)

2.02**(0.47)

Marginal impacts of Temperature and Precipitation

Climate Impacts

PCM 2100

CCSR2100

CCC2100

Dryland

ΔNet Revenue(USD/ha)

+160.6(50.8%)

-116.6 (-36%)

-137.4(-43%)

Irrigated

ΔNet Revenue(USD/ha)

+352.0(30%)

-416.6(-36%)

+341.4(29%)

All Farms

ΔNet Revenue(USD/ha)

+212.5(48%)

-46.3(-10%)

-143.7(-33%)

African Livestock

• No data on farm value

• No data on land used

• Estimated net revenue per farm

• Estimated livestock owned per farm and then net revenue per livestock owned

Net revenue per farm

Value of livestock owned

Net revenue per livestock value in US$ 1000

Variable Coef. T-stat. Coef. T-stat. Coef. T-stat.

Temperature * small 1

-1260. -3.27

-1049

. -1.71 -49.9 -2.53

Temperature sq * small 1 29.6 3.51 28.2 2.10 0.55 1.28

Precipitation * small 1 -46.6 -2.14 -103. -2.98 -13.41 -12.05

Precipitation sq * small 1 0.20 1.79 0.47 2.60 0.07 13.17

Temperature * large 1

-323.7 -0.82

1351. 7.15 14.90 2.43

Temperature sq * large 1 -0.23 -0.03 -42.8 -7.21 -0.50 -2.59

Precipitation * large 1 -99.0 -4.51 -7.62 -0.20 -2.67 -2.19

Precipitation sq * large 1 0.28 2.26 -0.32 -1.47 0.01 1.07

Log household size -1024. -3.31

-2240.

-4.55 10.57 0.66

Electricity dummy 2469. 5.64 4960. 7.13 219.5 9.72

Population density 79.1 2.75 126.6 2.77 11.55 7.96

Population density sq -1.16 -3.65 -2.13

-4.21 -0.12

-7.79

% Muslim -2640. -2.81-

4508.-

3.02-

31.75-

0.75

% Grassland 9799. 7.182295

2.10.5

8

Adj Rsq 0.20 0.20

N 4763 4763

TYPES

Current livestock income ($/farm)

Marginaltemperature impact ($/C˚)

Marginalprecipitationimpact ($/mm)

Temperature elasticity

Precipitation elasticity

Net revenue per farm

SMALL 105 108.8* -19.6* 24.0* -12.5*

LARGE 3291 -334.2 -64.7* -2.30 -1.20*

Value of livestock owned

SMALL 259 256.8* -41.0* 22.9* -10.6*

LARGE 7795 -357.9* -93.0 -1.04* -0.73

Net revenue per livestock value

SMALL 0.371 -0.024* -0.004* -1.51* -0.63*

LARGE 0.394 -0.033* -0.006* -1.87* -0.94*

AGGREGATE IMPACT

Impact per small farm($/farm)

% of livestock income Impact per

large farm($/farm)

% of livestock income

2100    

CCC +2034.56 +322.9% -830.62 -26.4%

CCSR +1391.33 +220.8% +142.55 +4.5%

PCM +337.59 +53.6% -720.25 -22.9%

Results

• Ricardian analysis reveals climate is important to African crops and livestock

• Warming is likely to be harmful to African crops and can be harmful to livestock

• Increased precipitation is generally beneficial to African agriculture

• Impacts can be immediate to countries that are currently hot and/or dry