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Climate and Agricultural Risk. Drs. Reddy, Amor Ines, Sheshagiri Rao. Overview. I. Drivers of agriculture risk (climate and non-climate) II. Analyzing variability at different spatial and temporal scales Yield variability and spatial scales Rainfall variability across time
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Climate and Agricultural Risk Drs. Reddy, Amor Ines, Sheshagiri Rao
Overview I. Drivers of agriculture risk (climate and non-climate) II. Analyzing variability at different spatial and temporal scales • Yield variability and spatial scales • Rainfall variability across time III. Analyzing roles of climate and non-climate factors in yield variability • Using de-trending to separate low-frequency and high frequency influences on crop yield variability • Yield Analysis: Mahabubnagar case
Overview contd… IV. Implications of variability for decision making • Decisions are dynamic • Limitations of using average values V. Identifying various levels of spatial analysis • Options for decision making on climate risk and opportunities • Time horizons in decision making • Role of different decision makers VI. “Good” and “bad” years • What are good and bad years? • Methods for analyses: Z-score approach and Percentile Threshold approach VII. Weather Manager: Tool for analyzing weather data
I. Drivers of Agricultural Risk and Across Scales • Climate (temperature/rainfall extremes) • Prices (of seeds/inputs, mandi prices) • Institutions (banks and access to credit, community support groups, etc) • Policies (subsidies, government relief programs, water/land access rights, etc)
II. Analyzing Variability Across Scales • Yield Variability and Spatial Scales • Rainfall Variability across Time
Scale and Yield Variability Variability of groundnut yields at multiple scales, residuals about smoothed trend.
Scale and Yield Variability Variability of groundnut yields at multiple scales, residuals about smoothed trend.
Scale and Yield Variability Variability of groundnut yields at multiple scales, residuals about smoothed trend.
Scale and Yield Variability Variability of groundnut yields at multiple scales, residuals about smoothed trend.
Scale and Yield Variability Variability of groundnut yields at multiple scales, residuals about smoothed trend.
Spatial (Rainfall) Variability Dependable rainfall (mm) in different regions of Andhra Pradesh
Temporal (Rainfall) Variability Annual rainfall (mm) trend in Andhra Pradesh Mean Rainfall Trend line
Temporal (Rainfall) Variability Rainfall deviation (%) over Andhra Pradesh
III. Climate variability (and de-trending) Analyzing roles of climate and non-climate factors in yield variability • Using de-trending to separate low-frequency and high frequency influences on crop yield variability • Yield Analysis: Mahabubnagar case
Climate variability and de-trending Impact of the deficits of the monsoon rainfall significant despite the technology inputs
Yield Analysis – Mahabubnagar Example III. Climate variability and de-trending
Yield reconstruction using three datasets Kg/ha Year
Yield reconstruction and de-trending Kg/ha Year
Yield residuals (=Yobs/Ytrend-1) Kg/ha Year
Yield reconstruction and de-trending A low-pass Fourier-based smoother is used Kg/ha Year
Yield residuals (=Yobs/Ytrend-1) Residuals
Yield residuals (=Yobs/Ytrend-1) Residuals
IV. Implications of Variability for Decision Making • Decisions are dynamic • Limitations of using Average Values
Station Rainfall Variability Months
Average Monthly Rainfall Months
Exeedence Probability of Rainfall JJA JAS Rainfall amount, mm
V. Levels of Spatial Analysis • Spatial levels decision making • Options for decision making on climate risk and opportunities • Time horizons in decision making • Role of different decision makers
FOREFITED OPPORTUNITY HARDSHIP CRISIS Managing the Full Range of Variability
Diversification and RiskLow Correlation + Diversification = Reduced Risk A & B independent random normal Ct = 0.5 At + 0.5 Bt SDA = 1.03, SDB = 0.96, SDC = 0.51
Avinashi, TN Optimal crop mix: groundnut-sorghum cotton Maximize CEincome Diversification and Risk
Levels of Spatial Analysis Crop mixes with Negative correlation in yield – Non overlapping critical periods
Levels of Spatial Analysis Family wise Cattle population in 6 villages.
Family wise sheep and Goat income- 6 villages Levels of Spatial Analysis
Highest number of animals not with the largest of farms Levels of Spatial Analysis
VI. “Good” and “Bad” years • What are good and bad years? • Two methods for analysis • Percentile Threshold Approach • Z-score Approach
Reality on the ground Examples from Mahabubnagar illustrating multiple factors that determine good and bad years Higher night temperature (4.5oC) from Nov. –Dec, 1997 resulted in severe outbreak of Helicoverpa Higher sun shine hours (3-4 hrs over normal) during Jan, Feb and March, 1998-98 enhanced the yield level of rice and groundnut and pesticide usage has come down
Z-score (Residuals) Z=(x-mean)/sd
Residuals Probability X
Seasonal Rainfall-JAS: ENSO States mm Years
VII. Weather Manager • Tool for Analyzing Weather Data