climate change and agriculture evaluating the impacts of mitigation and adaptation projects irina...
TRANSCRIPT
Climate change and agricultureEvaluating the impacts of mitigation and
adaptation projects
Irina Klytchnikova, Economist, World BankBrasilia, November 2009
Why are we talking about climate change today?
• Impact of climate change on agriculture in Latin America and adaptation options in agriculture
• Potential for mitigation of GHGs in agriculture in Latin America and mitigation options in agriculture
• Through the lens of impact evaluation
IMPACT OF CLIMATE CHANGE ON AGRICULTURE IN LATIN AMERICA
5
Potential Impact on Agriculture — Projected Percentage Change in Agricultural Productivity in 2080
Note: Scenario: SRES A2.Source: Cline 2007.
Extreme weather events will be more frequent, often leading to natural disasters
• Example: more consecutive dry days– México, Central America, Brazil,
Bolivia, Chile (2030)– Affected areas are in many cases
already exposed to high drought risk
• But in Central America risk also of more intense hurricane-related rainfall:– Losses from hurricanes could
triple by 2020-25, reaching 6% of GDP
Source: WB staff calculations with data from 8 global circulation models.
HIGH GHG MITIGATION POTENTIAL IN AGRICULTURE IN LATIN AMERICA
LAC’s Share of Global GHG Emissions : 12.5% overall, but 31% of LULUC
12.5
42.5 45.1
11.6
44.8 43.6
5.6
59.9
34.531.0
-3.6
72.6
-30
-10
10
30
50
70
90
Latin America Industrialized Countries Other Developing Countries(excluding LAC)
% o
f T
ota
l
Total GHG Emissions (CO2, CH4, N2O, PFCs, HFCs, SF6)Total CO2 Emissions Total CO2 Emissions excluding land use change CO2 Emissions from land use change
Source: Climate Analysis Indicators Tool (CAIT), Version 5.0. Washington, DC: World Resources Institute (WRI), 2008.
By country, LULUC emissions are highest in Brazil, but other countries’ LULUC emissions also are high as share of their
total
Share of emissions from LULUC by LAC Country (2000) LAC emissions from land use change
Brazil, 58%
Peru, 8%
Rest of LAC, 8%
Colombia, 5%
Bolivia, 4% Chile, 1%
Argentina, 2%Guatemala, 2%
Ecuador, 2%
Mexico, 4%
Venezuela, 6%
Share of Land Use Change in total GHG Emissions (%)
73%
68%
60%
59%
58%
40%
39%
37%
16%
16%
14%
Peru
Guatemala
Ecuador
Brazil
Bolivia
Rest of LAC
Colombia
Venezuela
Argentina
Chile
Mexico
Source: Climate Analysis Indicators Tool (CAIT) Version 5.0. (Washington, DC: World Resources Institute, 2008).
Beyond the forests: agriculture has high technical mitigation potential in LAC
Source: Smith and others (in press).
Many mitigation options in agriculture and many of them low-cost
Mitigation costs in agriculture for two climatic zones typical of the LAC region.
0
10
20
30
40
50
60
70
US$
per
ton
CO
2-eq
. per
yea
r
Warm-moist
Warm-dry
Notes: Estimated marginal costs of mitigation are only indicative of the relative magnitudes. Actual costs significantly vary depending on the local climatic and socio-economic conditions. The estimated costs of manure management (around US$200 per tCO2-eq.) and water management (around US$2,500) are not shown in the figure. The estimated marginal cost of agro-forestry ranges from a high of US$119 in cool-dry climates to a low of $28 in warm-moist zones. For tillage, the range is from US$7 to US$30 according to these estimates.Source: Smith and others (in press).
MAINSTREAMING ADAPTATION TO CLIMATE CHANGE IN AGRICULTURAL PROJECTS
Examples of adaptation measures
• Genetic improvement – wheat, maize, oilseeds• Integrated watershed management• Improvement to irrigation systems • Revalidation of agricultural technologies• Early alert system• Crop diversificationExample of a World Bank project• Mainstreaming Climate Change Adaptation in Irrigated
Agriculture in China (2008)• Studies to set priorities in adaptation and develop national
adaptation strategies in Latin America
BUT ARE ADAPTATION PRACTICES ADOPTED BY FARMERS?
MITIGATION OF CLIMATE CHANGE THROUGH BETTER SOIL AND PASTURE MANAGEMENT
CASE STUDY OF THE INTEGRATED REGIONAL SILVOPASTORAL PROJECT: QUINDIO, COLOMBIA
(Source: Pagiola and Rios, forthcoming)
Supporting Silvopastoral practices helps store carbon and protect biodiversity
• Regional Integrated Silvopastoral Approaches to Ecosystem Management Project in Colombia, Costa Rica, and Nicaragua– (1) planting high densities of trees and shrubs in pastures,
thus providing shade and diet supplements while protecting the soil from packing and erosion;
– (2) cut and carry systems, in which livestock is fed with the foliage of specifically planted trees and shrubs (‘fodder banks’) in areas previously used for other agricultural practices; and
– (3) using fast-growing trees and shrubs for fencing and wind screens.
Benefits to farmers
• The on-site benefits of silvopastoral practices to land users – additional production from the tree component, such as fruit,
fuelwood, fodder, or timber– maintaining or improving pasture productivity by increasing nutrient
recycling– diversification of production
• Off-site benefits– a major role in the survival of wildlife species by providing scarce
resources and refuge– helps protect native forest plants– shelter for wild birds– help connect protected areas– carbon fixing in soil and trees
Costs to farmers
• While these benefits can be important, they are often insufficient by themselves to justify adopting silvopastoral practices– Upfront tree planting costs and benefits several
years later– Estimates prepared for the project show rates of
return of between 4 and 14 percent, depending on the country and type of farm (Gobbi, 2002)
HOW TO EVALUATE THE IMPACT OF THE PROGRAM? FIRST, IN THEORY…
Randomized trial, “the gold standard”
• Randomized trial, “gold standard” in impact evaluation– In Mexico, the ending of the first round of PSAB contracts in
2008 provided an opportunity for a randomized trial.– Proposal was that only half of the communities whose
contracts were expiring, chosen at random would be re-enrolled (all had indicated their desire to do so).
– The land use choices of the entire cohort would then be monitored for several years.
– Assess the effect of actually participating to be assessed (Pagiola, 2007).
– But – not implemented due to political constraints
Control group method, not as golden but more feasible
• Control group method with random assignment of participants to control and treatment group– Preferable from the evaluation point of view but may be
politically difficult– Solution: plan project implementation in stages, randomly
assign participants to stages– Another solution: Control group method with non-random
assignment • Control group consisting of households with similar
characteristics (farm size, type of activities, agroecological conditions)
• Problem: control group will very likely turn out to be different and estimation of program impact may be biased
Evaluating the effect of a PES program with a control group
Control group with very similarcharacteristics as
the treatment group(farmers who would like to and cannot
participate in the program)
Treatment group(farmers who would like to participate
in the program and do)
Evaluating the effect of a PES program and technical assistance (TA)
Control group (no PES
and no TA)
Treatment group (receives PES) Control group
(TA but no PES)
Treatment group (receives PES and TA)
COMMUNITY WITH TA COMMUNITY WITHOUT TA
But how large should a sample be?
• Generally, the sample size will need to be larger the greater is the number of treatments for which we want to evaluate impact
• So, to evaluate the effect of PES with and without Technical Assistance (or of Technical Assistance alone) the sample size will need to be larger
• How large? Remember Laura’s presentation…
HOW TO EVALUATE THE IMPACT OF THE PROGRAM? NOW, IN PRACTICE…
Hypothesis
• Receiving PES is an incentive to change land use
• Receiving Technical Assistance (TA) is an incentive to change land use
Study characteristics
• PES Recipients– With technical assistance (48)– Without technical assistance (24)
• Control group– Without PES and without technical assistance
(29)– Chosen from the universe of those who
wanted to participate in the program
Impact of PES
Impact of PES
WHAT ABOUT THE IMPACT ON INCOMES AND ARE MEN AND WOMEN AFFECTED DIFFERENTLY?
IS THE PAYMENT TOO LOW OR TOO HIGH?
WHAT TOOLS ARE AVAILABLE TO IMPROVE PROJECT’S TARGETING TO MAXIMIZE ENVIRONMENTAL BENEFITS?