DRC 2006.Presenter’s Name.March 7-9.p 1

California’s enormous computing resources allow climate simulations at unprecedented resolution capturing

California’s regional climate phenomena

50Km resolution

9 Km resolution

Target Resolutions

Global: 15 Km

Regional: 1 Km Duffy and Taylor

DRC 2006.Presenter’s Name.March 7-9.p 2

California’s complex terrain drives the need for high resolution climate models

Wintertime precipitation rate

Duffy

DRC 2006.Presenter’s Name.March 7-9.p 3

Local forcings (such as irrigation) are critical to understanding local climate change

Observed trends

Natural variability and trends in California temperature records

Deg

ree

Cnatural internal variability (from model simulations)

Winter Spring Summer Fall

Data for 2000

Developed by Food and Agriculture Organization and David Lobell

Annual irrigation data

DRC 2006.Presenter’s Name.March 7-9.p 4

Federal, State, and academic partnerships are key to making progress in regional climate

• Federal – DOE – energy use impacts on regional climate

• DOE Program on climate simulation diagnosis and analysis• Large compute resources

– NOAA – climate prediction mission• Existing regional climate assessment centers via RISA program

– NASA – Earth science R&D and satellite observations• Modeling analysis and data assimilation; large compute resources

• State– CEC – Energy and climate research in CA

• Funding climate change research (regional climate, impacts, adaptation, inventory methods, emission reductions, …) since 2003 ($6M/year)

• Leadership in CA Biennial Assessment

– CARB – implementation of AB32

• Universities• Innovative models and modeling approaches (e.g., parameterizations)• Ground based observation stations and modeling analysis• Educating next generation of researchers

DRC 2006.Presenter’s Name.March 7-9.p 5

Aerosols transported across the Pacific are dramatically impacting California’s air quality standards

1950 - 1990l N. America: SO2 decreased from 41% to 17%.l Asia: SO2 increased from 7% to 37%.

Regional percentage of fossil fuel SO2 emissions (Dignon)

N America

L AmericaFSUOceania

EuropeAsiaAfrica

34%

1%13%

2%

7%2%

41%

1950

Total: 30.2 TgS Total: 56.6 TgS

Total: 59.0 TgS Total: 70.4 TgS

26%

25%1%

4%18%

5%

21%

1980

37%

19%1%

4%17%

5%

17%

1990

21%

26%

1%

2%

28%

4%

18%

1970

Currently 25% of PM2.5 limits in CA are caused by aerosol transported from across the Pacific

China is building 1 GW of fossil fuel power plants per week

CameronSmith

DRC 2006.Presenter’s Name.March 7-9.p 6

Diminished mountain snowpak will reduce water supplies

Impacts residential, commercial, agriculture, and energy production

DRC 2006.Presenter’s Name.March 7-9.p 7

Climate change could prove disastrous for our nation’s levees

Rising sea levels combined with “wetter” storms will likely cause levee failures

Mauer

DRC 2006.Presenter’s Name.March 7-9.p 8

Increases in California temperatures will cause decreases in crop productivity

DRC 2006.Presenter’s Name.March 7-9.p 9

Regional Climate Summary

• Climate modeling at the global and regional scale is critical to understanding California’s climate change impacts and forming strategies in adaptation and mitigation

– Resolving the important processes driving climate change is important– New science understanding is important

• Climate models (as always) depend on quality observations– Evaluate, diagnosis, analyze, and improve

• Climate change will strongly impact California’s future in air quality, water resources, and agriculture (also human health, and others)

• A partnership across Federal, State, and Academic institutions is required to make progress in understanding and addressing climate change at the regional and local scale

• As Charlie Kennel said – Its global, its regional, and its local

DRC 2006.Presenter’s Name.March 7-9.p 10

Backup

• Backup

DRC 2006.Presenter’s Name.March 7-9.p 11

Climate simulation/analysis focuses more and more on regional issues

• Why?

• Because humans and natural ecosystems experience regional, not global, climate;

• Because improvements in climate models make meaningful regional projections possible

• Regional climate changes will determine societal impacts and drive climate-related policy decisions

Water availability

RecreationExtreme events

Air quality

Human health

Agriculture

DRC 2006.Presenter’s Name.March 7-9.p 12

Regional models can represent major characteristics of California’s precipitation patterns

DRC 2006.Presenter’s Name.March 7-9.p 13

Irrigation database over California is a sub-county resolution

% irrigation

100

0

Data for 2000

Developed by Food and Agriculture Organization and David Lobell

DRC 2006.Presenter’s Name.March 7-9.p 14

River flow measurements show changes in runoff timings

during the 20th century – is this climate change?

• Rivers depending on snowmelt show earlier flow patterns

• Rivers dependent on precipitation show later flow patterns

Cayan et al., Bull. AMS. 2001; Stewart et al., J Clim., 2005Cayan et al., Bull. AMS. 2001; Stewart et al., J Clim., 2005

Springpulse

Center time

Trends in SP (1948-2000)