international ricardian studies. marginal impacts of temperature and precipitation
TRANSCRIPT
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