Joanna Syroka, Addis Ababa, Ethiopia 21 January 2008 Triggering Early LP Costs for Drought using LEAP
Challenge Input Data: –LEAP water balance model calculations –Objective estimates of crop yield deviations due to water stress (and therefore rainfall) Calculations: –A methodology that relates water balance calculations to beneficiary numbers per region –Fixed at the beginning of the season Output Data: –LP Costs per region, varying only due to rainfall CALCULATIONS (in LEAP) INPUTOUTPUT To create an objective index that can be used to trigger early Livelihood Protection costs to regions for PSNP and non-PSNP drought needs
Approach It must be simple, transparent and robust To establish the calculation methodology we must compare LEAP water balance output to historical beneficiary numbers The final index should be able to target both PSNP and non-PSNP weredas, therefore wereda-level data needed: 1.LEAP water balance output specified for locally grown, dominant crops, WBI wereda E.g. adjusted for local varieties, soil type etc. Take into account Belg and Meher yields where appropriate Historical DPPA data : Total Emergency Beneficiary Numbers : PSNP + Emergency Beneficiary Numbers Output data is only as good as inputs used!!
Calculation Methodology A simple linear regression to relate a historical Regional Drought Index (Y, independent variable) to a Regional Total Beneficiary Estimate (N, dependent variable), i.e. N = a * Y + b –The intercept and slope, b and a, are estimated by the intercept and slope of the least-squares regression line Historical Y values against historical DPPA data per region (adjusted for population growth), for rainfall seasons –N gives the estimated total number of beneficiaries (chronic + transient) in the region Benefits: Confidence bands can be statistically calculated; least amount of assumptions about underlying data
N = a * Y + b Y N
Regional Drought Index, Y LEAP water balance output for each wereda is weighted by relative wererda vulnerability and aggregates over the region –“Yield” variations in most vulnerable weredas contribute most to the regional drought index –Vulnerability defined in terms of the wereda’s relative vulnerable population of the region Y = (Σ wereda WBI wereda *ARP wereda )/ARP region –WBI wereda : Water balance output specified crop(s) in wereda –ARP wereda : At-Risk Population in Wereda = Historical Maximum Ever Population in Need in Wereda (i.e. PSNP + Emergency for ) –ARP region : At-Risk Population in Region = Σ wereda (ARP wereda )
Y = / = 53% for this season 40% 60% 70%90% WBI wer Ave = 63% 1. 10, , , , , , , At-Risk Pop Region & Weredas
Regional LP Cost Estimate If the Regional Total Beneficiary Estimate, N for a given Y input value is > Total Number of PSNP Beneficiaries, PSNP, in the region: –It is assumed that additional assistance is needed by the region to deal with the increased number of beneficiaries and needs –Reg LP Cost Estimate = max(0, N - PSNP)*C C is the Cost per Additional Beneficiary (e.g. $34) to estimate the additional funding costs needed by the region in such as scenario –Confidence Bands can be calculated by using the Standard Error (SE) in N, i.e. i.e. N –/+ *SE Where specifies the desired confidence level If not, the PSNP is assumed to be able to take care of all drought-related needs within the region.
Limitations of Approach As for all methods, only as good as the input data used: –“GIGO: Garbage in garbage out” Assumes a linear response between drought stress on yields and early LP costs –Transparent, but the most “accurate”? Uses data from to establish the calculation parameters a and b –How will extreme drought events, like 2002, look like in a PSNP world? –Will the response (a and b) be the same? –Ongoing process, needs to be continuously refined and improved Focuses on drought risk only –Not flood, price, pest, “green famine”, civil unrest etc.
Triggering Early LP Costs for Drought using LEAP: Preliminary Results for
Inputs Used To establish a and b: 1.WBI wereda : LEAP water balance output specified for either maize, sorghum or rangeland – Taking into account Belg and Meher where appropriate , using NOAA rainfall satellite data 2.Historical DPPA data, adjusted for population growth (2.9% per year) : Total Emergency Beneficiary Numbers : PSNP + Emergency Beneficiary Numbers To calculate early LP costs: –PSNP population per region –C, Cost per Additional Beneficiary = $34
Tigray Region Correlation: 57% PSNP < 55
Amhara Region PSNP: 2.5 mil No Historical Triggered Payouts Correlation: 60%
Oromia Region PSNP < Correlation: 56%
SNNPR Region PSNP 1999 Correlation: 64%
Afar Region PSNP < Correlation: 65%
Total Beneficiaries for All Regions (minus Gambella and B-Gumuz) Correlation: 85% PSNP
Historical Early LP Costs for PSNP Regions i.e. N > PSNP per Region
$25 Million Contingent Grant
Historical Early LP Costs for All Regions (minus Gambella and B-Gumuz)
Historical Early LP Costs for All Regions Assuming 20% PSNP Contingency $25 Million Contingent Grant
Historical Early LP Costs for All Regions Assuming Increasing PSNP Levels from 1996 to Capture Increasing Vulnerability
Recommendations LEAP can be used to index beneficiary numbers and therefore should be! Works needed to improve the input data as much as possible: –Input LEAP water balance calculations –DPPA data Model must be continually improved and refined as more data post 2005 becomes available and more verification work is done