Preliminary results. Exploratory patterns rather than looking into absolute numbers. Why we did (background), summarize some results from phase IIB,

Transcription

1 Preliminary results. Exploratory patterns rather than looking into absolute numbers. Why we did (background), summarize some results from phase IIB, introduce approach, results, implications 1

2 Climate Adaptation Legislation: A package of three bills was signed into law by Governor Brown to improve California s resilience to climate change AB 2800: requirement for all state agencies to take the current and future impacts of climate change in all aspects of infrastructure planning, investment, and maintenance, California s Climate Adaptation Strategy DRAFT for discussion 2

3 Reservoir systems in all basins. Reservoirs provide spaces resilience and flexibility in droughts and floods Reservoir operation depends on Reservoir inflows. Climate change and variability affect reservoir inflows affect vulnerability 3

4 CVFPP climate change study Key River Basins in the Central Valley. The study focuses on 12 watersheds of the two basins. The study looked into change in hydrograph characteristics of these 12 watersheds. 4

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6 Area elevation curve/hypsometric curve: elevation is a key factor in a climate change analysis form of precipitation depends on it. 6

7 Let us first begin by revisiting CVFPP climate change analyses viz. basin avg and 3 day annual maxm precipitation 7

8 Mean Annual Temperature for Sac and SJ basins. (Based on BCSD data) GCM CMIP5 Mean annual Precipitation (Based on BCSD data) GCM CMIP5 Projected Changes in Mean Annual Precipitation for the Sacramento River Basin (SAC) and San Joaquin River Basin (SJ) Based on CMIP5 Projections. The changes are computed using over 100 downscaled climate projections simulated under RCP emission scenarios RCP8.5, RCP6.0, and RCP4. Base Period is The box represents the interquartile range (IQR) between the lower (Q1, 25 th percentile) and the 8

9 upper (Q3, 75 th percentile) quartiles. The upper (lower) whisker is at the smaller (larger) of maximum (minimum) value of the variable and 1.5 times the interquartile range above (below) the median 8

10 Mean annual Precipitation (Based on BCSD data) GCM CMIP5 Projected Changes in Mean Annual Precipitation for the Sacramento River Basin (SAC) and San Joaquin River Basin (SJ) Based on CMIP5 Projections. The changes are computed using over 100 downscaled climate projections simulated under RCP emission scenarios RCP8.5, RCP6.0, and RCP4. Base Period is The box represents the interquartile range (IQR) between the lower (Q1, 25 th percentile) and the upper (Q3, 75 th percentile) quartiles. The upper (lower) whisker is at the smaller (larger) of 9

11 maximum (minimum) value of the variable and 1.5 times the interquartile range above (below) the median 9

12 What does the extreme projected precip says? precip is important for flood management consideration. 10

13 Define CCTAG LOCA Purpose And The approach DRAFT for discussion 11

14 Explain How to define flood event? Different approaches. Simple 10% approach. Caveats exist. Purpose Learn the seasonality aspects, relative sense. Absolute numbers do not make any sense. 12

15 Key message? 13

16 Key message? 14

17 Key message Increasing median, and 90 th percentile flow. Statistically significant? What is 90 th percentile here? 90 th Percentile has higher slope of trend? 15

18 CCSM4 EXTRA PEAK RCP8.5 Key message? Implications? 16

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24 Departure from Base Period; 11 year running mean 1985 present : 1.81 degree per century 1949 present : 3.10 degree per century 1975 present : 4.40 degree per century 22

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26 Key message? Uncertainty and pattern of increase precip 24

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28 CCSM4 EXTRA PEAK RCP8.5 Key message? Implications? 26

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