I. GCASE: Methodology Climate change impact assessment on water resources

Eylon Shamir (presenter) Eshamir@hrcwater.org

Hydrologic Research Center, San Diego www.hrcwater.org coauthors:

Sharon B. Megdal and, Susanna Eden Water Resources Research , University of Arizona (UA)

Karletta Chief, Soil Water & Environ. Sciences, UA &

Cristopher Castro, Atmospheric Sciences, UA

Funded by, NOAA Climate and Societal Interactions

Sectoral Applications Research Program (SARP)

Exploring the Transferability of the GCASE Methodology to Locations in Sonora, Mexico , Esplendor Hotel Rio Rico, Arizona November 13, Orange, CA July 31, 2014

1. Develop water resources decision support modeling framework that addresses future climate uncertainties

-Climate scenarios and surface water flows -Linkages to groundwater recharge -Linkages to water management decisions

2. Increase stakeholders’ capacity to adapt water planning and management to future climate uncertainties

3. Establish transferability of the modeling approach and stakeholder engagement

Project Goals and Approach

2

Santa Cruz River - Alluvial Aquifer

3

Seasonal Precipitation &

Streamflow

1950 1960 1970 1980 1990 2000 20100

50

100

150

200

250

300

350

400

Years

Rai

nfal

l (m

m/s

easo

n)

Nogales Gauge

WinterSummer

1950 1960 1970 1980 1990 2000 20100

2

4

6

8

10

12x 10

4

Years

Stre

amflo

w (1

000

m3 /s

easo

n)

Nogales Gauge

WinterSummer

RAINFALL STREAMFLOW

4

Precipitation Categorization

5

SUMMER (Jul-Sep) WINTER

WINTER (Nov-Mar)

Future Likely Rainfall Scenarios

Rainfall Generator

6

Hydrologic Modeling Framework

7

Climate Scenarios

Climate and Hydrologic Models

Global Circulation

Models

Regional Mesoscale

Models

Watershed Hydrologic

Models

Downscale

Input

• General climatology patterns ocean-land • Pacific sea surface temperature and relations

to SW climatology • Trade wind, atmospheric rivers etc. • General climatology of temperature and precip.

• Spatial distribution of climatological variables due to terrain and microclimate

• Special regional features • Summer rainfall, snow • Regional prevalent synoptic conditions

• Developed using local high resolution data • Further refinement of microclimate features • Interaction – surface –Groundwater • Feedback with management decision

8

9

0 0.5 1 1.5 2 2.50

0.5

1

Average (mm/day)

Statisticaly Downscaled BCSD5 1/8o

Observed Nogales GaugeHistoric Interpolation 1/8o

0 1 2 3 4 5 6 70

0.5

1

Standard Deviation (mm/day)

Cum

ulat

ive

Dis

tribu

tion

0 20 40 60 80 100 120 140 160 180 2000

0.5

1

Rainy Days (count)

Issues with widely used climate impact assessment procedures

Statistical Downscaled CMIP 3 &5

Climate and Hydrology Projections

http://gdo-dcp.ucllnl.org/downscaled_cmip_projections/

Precipitation from 8 IPCC-AR3, A2 emission scenario, dynamically downscaled regional

climate models

No. Regional Model Resolution 1 Max Planck Institute (MPI) 35 km2, 6 h,

1950-2100 2 Hadley center (HADCAM3) 3-8 North American Regional

Climate Change Assessment Program [NARCCAP]

50km2, 3 h, 1970-2000 2040-2070

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8 Regional Climate Models

Projected Wetness by 8 models SUMMER

• 7 models projected MORE DRY summers

• Only 2 models projected MORE WET summers

WINTER • 8 models projected MORE DRY

winters • 6 models projected MORE WET

winters

1

2

3

4 5 6 7

1 2 3

4 5 6

7

8

8 Regional Climate Models 11

Regional Climate Model

1960 1980 2000 2020 2040 2060 2080100

150

200

250

300

350

400

450

500

550

Years

Rai

nfal

l (m

m/S

easo

n)

MPI Summer [July-September]

Seasonal10-Yr Moving Avg.Tercile Boundaries

Clear reduction in Summer

#2

Projection

1960 1980 2000 2020 2040 2060 20800

100

200

300

400

500

600

700

800

Years

Rai

nfal

l (m

m/S

easo

n)

MPI Winter [November-March]

Seasonal10-Yr Moving Avg.Tercile Boundaries

Higher variability in Winter

#2

Projection

12

Summary

• We developed a modeling framework that is capable to generate ensembles of likely realizations that represent the climate variability of rainfall, streamflow and ground water recharge

• Climate projections indicate: – higher frequency of dry summers – lower frequency of wet summers – higher frequency of dry and wet winters

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