Climate Change and Climate Variability : Bangladesh Perspectives
Climate variability, climate change and agriculture
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Transcript of Climate variability, climate change and agriculture
Variability/Change?
• Many African societies are well-adapted to the climate variability to which they are exposed
• This variability is a good proxy for risks associated with future climate change, provided that the rate of change is sufficiently slow
(Mortimore, 1998, Brooks and Adger, 2003)
Dealing with variability
• Identification of response strategies• Availability of Climate information• Historical data and response strategies • Community/indigenous knowledge• Forecasts of differing scale, skill, time
frames• Trials (and error)
DECISION FRAMEWORK ON CLIMATE VARIABILITY ANDCLIMATE CHANGE
TYPE OF DECISION
CLIMATE WEATHER
Long Term (10-50yrs) Medium Term (6-9mths) Short term (0-7days)
Decadal Changes Seasonal Forecasts Real Time → Week
Strategic
Tactical
Operational
• Crop planning • Reservoir
planning• Land management• Capital
investments
• Crop management• Water allocation• Input costs/planning
• Irrigation scheduling • Operations planning• Time management
Terminology
• Normal (237 +/- 10% = 210-260 mm) • Above Normal (above 260mm)• Below Normal (below 210mm)
• % of normal predicted: 80% = 168mm60% = 126mm40% = 84mm
• 40-60% of normal = 84-126mm• 100-120% of normal = 237-284mm
= 237 mm
203545
3763
5580
Seasonal forecasts?
• 3 month regional scale projections produced for 1,2,3 month lead times
OND 2006Precipitation forecast (%of Normal)
User responses - Reliability
1. Accuracy – will it be correct?
Probability/likely/confidence?
2. Skill – how often will a forecast be correct?
3. Scale – usefulness?
4. Consistency – will the forecast for a particular month change?
5. Will I be able to interpret it?
Not enough information!
• What will the ENSO event mean?– Delayed onset?– Dry months?– Hot temperatures?
• Which crops are more susceptible?• Worst and best case scenarios…• Typical responses in analogue years..
Seasonal rainfall…
MALMESBURY Rainfall total/ave wheat yield 2000-2004
0.0
100.0
200.0
300.0
400.0
500.0
2000 2001 2002 2003 2004
mm
year
s
Rainfall
Yield x 100
Climate Change
• Longer term• More extremes• Changes in variability• Different coping skills?• Long term changes in pests, seasonal
lengths, water availability
Agricultural response
• Hedging opportunities and strategies• Diversification of crops/cultivars• Planting/fertilising strategy• Market/climate conditions/food prices• Weather forecast creativity….?
Farmer Issues on Adaptation to Climate Change
• Can farmers who are adapting prioritise beyond their own experience?– can they think out of the box?– or does some top-down advice have to be offered?
• Climate change is a special case within interacting drivers of change on the livelihoods of farmers
• Mainstreaming adaptation to climate change means a focus on vulnerability reduction– for this we need to seek multiple responses
PHYSICAL LIMITS
• Unsuitable soils• Lack of water
• Physically feasible but politically, socially or environmentally difficult
• Capacity of organisations• Capacity of individuals
After Arnell (2005)
FINANCIAL LIMITS
CAPACITY LIMITS
FEASIBILITY LIMITS
ADAPTATIONi.e. Adjustment to
altered circumstances
LIMITS TO ADAPTATION IN AGRICULTURE
Things to chew over..
• Can we make forecasts even more useful?
• Are tailored agricultural forecasts feasible?
• Do we have the required institutional capacity and skills?
• Will climate change projection information fit seamlessly into the dissemination networks that exist?