Increased water temperatures from CASCaDE climate-change scenarios:implications for selected California

fishes

Larry R. BrownU.S. Geological Survey,

California Water Science Center

Acknowledgments

• Thanks to CALFED Bay-Delta Program and USGS Priority Ecosystems Studies for funding

• Thanks to the CASCaDE Team for challenging questions and conversation

• I AM NOT A MODELER! I AM THE “FISH GUY”

CASCaDE ProjectUSGS: Daniel Cayan, Jim Cloern, Mike Dettinger, Neil Ganju, Bruce Jafee, Noah Knowles, Lisa Lucas, Sam Luoma, Nancy Monsen, Francis Parchaso, Dave Peterson, Dave Schoellhamer, Robin Stewart, Jan Thompson

Collaborators: Bill Bennett, Mark Stacey, Mick van der Wegen,WayneWagner, Christa Woodley

ComputationalAssessments ofScenarios ofChange in theDeltaEcosystem

Scenarios NOT predictions

Climate Change

Sea-Level Rise

Structural Changes

CASCaDE is building a 'cascade' of such models

Models can expand on our understanding of individual processes & responses to inform decision making by:

• Integrating & interrelating all processes

• Characterizing responses to simultaneous forcings

• Highlighting critical sensitivities

CASCADE Project: Why

Fish?• Fish integrate the

effects of all the physical and biological modeling

• Fish are of intense management interest because of effects on water policy

This Talk

Many different Global Climate

Models

-2

0

2

4

6

8

1975 2000 2025 2050 2075 2100

Tem

pera

ture

Cha

nge

(o C)

A1 HadCM3A1 PCMA2 HadCM3A2 GFDL2.1A2 PCMB1 HadCM3B1 GFDL2.1B1 PCM

consistent with California Climate Scenarios Assessment, 2006 and 2008

Mike Dettinger, Dan Cayan

Four Future Scenarios Considered

Which Models to Use?

Only time for 1 species:Delta smelt

• Federal and State listed as threatened• Petitioned for endangered status• Recent interest “high”

Delta smelt endemic to estuary

Mike Dettinger, Dan Cayan

Delta smelt example:

• Use Delta temperature models to assess changes in habitat

• Lethal limit about 25 C, prefer < 20 C

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38.1

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Longitude

Latit

ude

r2 vs. Position

0.9

0.92

0.94

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0.98

1

Statistical models of daily water temperature (prev. day, air temp.)

Wayne Wagner and Mark StaceyU.C. Berkeley

CarquinezStrait

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Longitude

Latit

ude

r2 vs. Position

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0.92

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0.98

1

Area Near Rio Vista Supports Large Population of Delta Smelt

100-Year Water Temperature Projections(medium warming)

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]Sac Rio Vista

gfdl b1measured

100-Year Water Temperature Projections(medium warming)

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]Sac Rio Vista

gfdl b1measured

Smelt threshold

100-Year Water Temperature Projections(medium warming)

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]

gfdl b1

2000 2010 2020 2030 2040 2050 2060 2070 2080 20900

10

20

30

40

50

60

70

80

90

100

Day

s/Y

ea

r >

25ο C

Sac Hood

• Significant increase in the number of days exceeding 250C under this scenario.

Projections (2010 - 2030)

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2010-2030) vs. Position

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl b1 forcing.

Not currentlyoccupied bydelta smelt

Projections (2040 - 2060)

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2040-2060) vs. Position

2040 - 20602010 - 2030

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl b1 forcing.

Not currentlyoccupied bydelta smelt

Projections (2070 - 2090)

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2070-2090) vs. Position

2070 - 20902010 - 2030

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl b1 forcing.

Not currentlyoccupied bydelta smelt

Biggest change along Sacramento corridor

Projections (2070 - 2090)

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl b1 forcing.

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2070-2090) vs. Position

2070 - 20902010 - 2030

Not currentlyoccupied bydelta smelt

100-Year Water Temperature Projections(most warming)

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]Sac Rio Vista

gfdl a2measured

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]Sac Rio Vista

gfdl a2measured

Smelt threshold

100-Year Water Temperature Projections(most warming)

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090

5

10

15

20

25

30

Tm

ax [ο C

]

gfdl a2

2000 2010 2020 2030 2040 2050 2060 2070 2080 20900

20

40

60

80

100

120

140

Day

s/Y

ea

r >

25ο C

Sac Rio Vista

• Dramatic increase in the number of days exceeding 250C under this scenario.

100-Year Water Temperature Projections(most warming)

Projections (2010 - 2030)

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl a2 forcing.

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2010-2030) vs. Position

Not currentlyoccupied bydelta smelt

Projections (2040 - 2060)

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2040-2060) vs. Position

2040 - 20602010 - 2030

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl a2 forcing.

Not currentlyoccupied bydelta smelt

Projections (2070 - 2090)

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2070-2090) vs. Position

2070 - 20902010 - 2030

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl a2 forcing.

Not currentlyoccupied bydelta smelt

-122.2 -122.1 -122 -121.9 -121.8 -121.7 -121.6 -121.5 -121.4 -121.3 -121.2

37.8

37.9

38

38.1

38.2

38.3

Longitude

Latit

ude

Days Exceedence/Year (2070-2090) vs. Position

2070 - 20902010 - 2030

Biggest change along Sacramento corridor

Projections (2070 - 2090)

Dot size is proportional to the average number of days per year in exceedence of 250C at each location under gfdl a2 forcing.

Not currentlyoccupied bydelta smelt

Delta Smelt Results

• Medium warming scenario results in more potentially lethal days

• Most warming scenario indicates Sacramento River no longer suitable habitat by mid-century

• Can delta smelt survive in Suisun Bay?– Salinity tolerance vs. temperature tolerance– 60-70% < 2 psu, 90% < 6 psu, lethal at 19 psu

Salty Fresh

Delta smelt are being found in

more saline water in

Suisun Bay

REMEMBER these are scenarios NOT predictions!

• Please do not leave thinking delta smelt are doomed

• Ideally, consideration of multiple scenarios might lead to more confidence in what the future of delta smelt might be

Next Steps for Delta CASCaDE

• Consider salinity (daily X2 just calculated) and temperature simultaneously

• Extend evaluation to other species