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ISP Meeting, Ouagadougou, 23 Oct 2012
Making Climate Information More Relevant to Smallholder Farmers
James Hansen, CCAFS Theme 2 LeaderIRI, Columbia University, New York
Prerequisites to benefitting from an information service
• Credibility
• Salience
• Legitimacy
• Access
• Understanding
• Capacity to respond
WG 1
WG 3
WG 2,4
WG 5
}Information product}Information service
Delivery system
}Users
Salience: What kind of information do farmers need?
• Types of climate information:
– Historic observations
– Monitored
– Predictive, all lead times ≤ ~20 years
• Some generalizations:
– Downscaled, locally-relevant
– Tailored to types & timing of decisions
– “Value-added” climate information: impacts on agriculture, advisories
– Capacity to understand and act on complex information
Anecdote 1: RCOFs for farmer decision-making?
“Weather-within-climate”
Probabilistic information needed for risk management
Capacity development through training, dialog with trusted advisors(http://www.wmo.int/pages/prog/wcp/wcasp/clips/outlooks/climate_forecasts.html)
climate community
“users”
applications
“…a hub for activation
and coordination of
regional climate
forecasting and
applications activities
into informal networks”
Basher et al. (Ed) (2001). Coping with Climate: A Way Forward. Summary and Proposals for Action. Palisades, New York: IRI.
• Owned, designed, convened by providers
• Spatial scale
• Seasonal rainfall total
• Probabilistic: Tercile format, often lost before reaching users
• Capacity development through stakeholder meeting participation
Anecdote 2: Early doubts about value of seasonal forecasts to farmers
• Error accumulates from:
– SSTs to regional rainfall
– Regional to local rainfall
– Local rainfall to crop yield
• Therefore prediction of climate impacts on farms is not feasible.
• Given the inherent uncertainty, poor farmers can’t bear the risk of a wrong forecast.
Barrett, 1998. AJAE 80:1109-12
• Depends on time horizon of decision
• Generalizations about increasing lead time:
– Decisions more context- and farmer-specific
– Information becomes more uncertain, hence more complex
– Therefore the scope of services needed increases
• “Weather-within-climate:”
– Timing of season onset, length
– Seasonal total = frequency × intensity. Frequency more predictable.
– Dry, wet spell length distributions
Elements of salience: Time scale
HOURS DAYS WEEKS MONTHS YEARS DECADES …
WEATHER CLIMATE
• Tillage
• Sowing
• Irrigation
• Crop protection
• Harvest
• Changing farming or livelihood system
• Major capital investment
• Migration
• Family succession
• Land allocation
• Crop selection
• Household labor allocation, seasonal migration
• Technology selection
• Financing for inputs
• Contract farming
Elements of salience: Spatial scale
Correlation of observed (85 stations) vs. predicted rainfall in Ceará, NE Brazil, as a function of spatial scale. Gong, Barnston, Ward, 2003. J. Climate 16:3059-71.
Co
rre
latio
n
Scale
Elements of salience: Communicating uncertainty
• Relate measurements to farmers’ experience
Elements of salience: : Communicating uncertainty
• Relate measurements to farmers’ experience
• Convert series to relative frequency, then probability
Oct-Dec rainfall (mm)
Year
s wi
th a
t lea
st th
is m
uch
rain
Elements of salience: Communicating uncertainty
• Relate measurements to farmers’ experience
• Convert series to relative frequency, then probability
• Explanation & repetition
?
Elements of salience: Communicating uncertainty
• Relate measurements to farmers’ experience
• Convert series to relative frequency, then probability
• Explanation & repetition
• Compare with e.g., El Niño years to convey forecast as a shifted distribution
Elements of salience: Communicating uncertainty
• Relate measurements to farmers’ experience
• Convert series to relative frequency, then probability
• Explanation & repetition
• Compare with e.g., El Niño years to convey forecast as a shifted distribution
• Explore management implications
Elements of salience: Translation to impacts on agriculture
• Example: Integrate seasonal forecasts into yield predictions
• Reduces uncertainty, more early in growing season
• Before planting, forecasts potentially more accurate for crop yield than for seasonal rainfall
Traditional sorghum, Dori, Burkina Faso. Mishra et al., 2008. Agric. For. Meteorol. 148:1798-1814.
Correlations of Jun-Sep rainfall, and observed, de-trended wheat yields with May GCM output, prior to planting, Qld., Australia. Hansen et al., 2004. Agric. For. Meteorol. 127:77-92
200 0 200 400 km
Correlation< 0.34 (n.s.)0.34 - 0.450.45 - 0.500.50 - 0.550.55 - 0.600.60 - 0.65 > 0.65
Rain
Yield
Elements of salience: Translation to management guidance
• At weather time scale, broadly-relevant advisories for time-sensitive decisions (sowing, irrigation, pest and disease control)
• At climate time scale, caution about top-down recommendations:– Decisions more farmer-
specific
– Uncertainty is greater
• Combine sources of expertise
• Involve trusted advisors
• Dialog with experts
• Farmer-to-farmer discussion
Institutional arrangements for salience?
• Limitations of supply-driven climate services
• Expanding the boundary to agricultural research and development
• Expanding the boundaries to give farmers a voice
CLIMATE SERVICE
NMS(climate)
User (farmer)
INFORMATION
CLIMATE SERVICE
NMS(climate)
User (farmer)
VALUE-ADDEDINFORMATION
NARES(agricultur
e)PARTNERSHIP
CLIMATE SERVICE
NMS(climate)
Co-owner(fa
rmer)
NARES(agriculture
)
PARTNERSHIP
Salience and historic data
• Local decision-making depends on local information.
• Many promising opportunities to adapt to climate variability and change depend on historic data, are constrained by gaps.
• In Africa, feasible to blend station and satellite rainfall data => complete 30-year, 5-10 km grid daily record. Extending to other agriculturally-important variables.
• Meteorological data policy – Is it time to consider change?STATION BLENDED SATELLITE