# Presentation: 622067

## Climate Change and Potential Impacts to Water Operations

- Levi Brekke (Reclamation, Technical Service Center)

- Presentation for the Bighorn River System Issues Group
- 29 July 2008, Lovell, WY

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent climate projections?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

##    “Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level.”

- IPCC (2007) Working Group 1 *Summary for Policymakers*

**Notes:**
Scientists have known about the greenhouse effect since 1824.  In the last twenty years
Scientist have grown increasingly concerned that humans are impacting our climate. 

The vast majority of scientists now believe that increases in GHGs since
The industrial revolution have warmed the planet, and will continue to warm the planet.

Still uncertainty, but not enough to delay action. Quote above

Basics of Hydrocycle
Extra Energy Means Enhanced hydrologic cycle
Globally Increased Evaporation and Precipitation 
More Intense Precipitation - Floods
More Intense Drying - Drought
Mid-Continental Summertime Drying
More Rain, Less Snow

If you don’t want to believe me, American Water Works Association has a booklet on climate change, and the two
Major scientific professional organizations that study climate have strong statements.

Please, please take the time to educate yourself on this issue. The climate
Of the earth is a fascinating topic and what scientists are able to discover from trees, lakes, oceans, ice cores is phenomenal. And their climate models are some of the most complicated computer programs anywhere. 

There are extra slides at the end of my presentation including
References. I’ll go anywhere to talk about this issue.

## Other Global Trends

- Global Mean Air Temperature

- Global average
- sea level

- Northern Hemisphere
- snow cover

- Fig.  IPCC (2007)

**Notes:**
Black lines are 10 year averages
Blue lines are 5-95% error bars (90 confidence intervals or said another way, 90% confidence that data falls within the blue bands)
Northern Hemisphere snow cover: Instrumental records only date back to 1920’s, which account for gap

## Western U.S. Climate

**Temperature**
**1950-1997 trend (Mote et al. 2005)**

**Precipitation**
**1976-2005 trend, “annual” inches/decade (www.cpc.noaa.gov/anltrend.gif)**

**Notes:**

Spring warm spell is defined as the time of first 7-day period with min temps above 52F.

Colorado shows significant warming as does most of the West.

## Bighorn Basin region:NOAA “Climate Division” data

- _[http://www.cefa.dri.edu/Westmap/](http://www.cefa.dri.edu/Westmap/)_
- Red = annual, blue = moving 25-year mean annual

## Historical Climate Division P data:WY-04 Bighorn 

- _[http://www.cefa.dri.edu/Westmap/](http://www.cefa.dri.edu/Westmap/)_
- Red = annual, blue = moving 25-year mean annual

- Historical Climate Division P data:WY-04 Bighorn

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent climate projections?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

## Explaining Temperature Trends

- “Attribution” Studies
- Model past Climate for two cases:
- ~All past “forcings”
- Only past _natural_ “forcings”
- Compare Results to Obs. (globally)...
- Need ~All “forcings” to explain observed

- Fig.  Andrea Ray

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent “climate projections”?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

## Making Climate Projections:steps before global climate modeling

- Econ/tech
- storylines

- emissionscenarios

- atmosphericconcentrations

- climate

- model

- model

- GCM

- Fig.  P. Chris Milly

## Global Climate Modeling objectives

- Huge amounts of water and heat move around the planet
- Evaporation, Ocean Currents

## More certain results: Temperature 

- Fig.  IPCC (2007)

## More certain results:Atmospheric Water, large areas

- More certain results:Atmospheric Water, large areas

- Fig. P. Chris Milly

## Less certain results:Precipitation, local/regional areas

- Fig.  David Yates

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent climate projections?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

## Temperature, three “scenarios”, results from multiple models 

- Fig.  IPCC (2007)

- Temperature, three “scenarios”, results from multiple models

## Precipitation, one “scenario” (A1b), results from multiple models 

- Fig.  IPCC (2007)

- Precipitation, one “scenario” (A1b), results from multiple models

## Downscaling:  relating GCM outputs to local/regional change

- Developers
- Santa Clara University (Ed Maurer)
- Reclamation
- LLNL
- Funding
- Reclamation
- DOE NETL

**http://gdo-dcp.ucllnl.org/downscaled_cmip3_projections/**

## Archive Scope

- Variables
- Precip rate (mm/d)
- Mean Daily Temp(°C)
- Attributes
- Monthly, 1950-2099
- 1/8°, contiguous U.S.
- Model Membership
- projected SRES paths A1b, A2, B1
- Simulated past climate (i.e. “20th Century Climate Experiment”)
- ...led to 112 projections selected for inclusion in archive

| # | WCRP CMIP3 Model I.D. | # A1b | # A2 | # B1 |
| --- | --- | --- | --- | --- |
| 1 | BCCR-BCM2.0 | 1 | 1 | 1 |
| 2 | CGCM3.1 (T47) | 1...5 | 1...5 | 1...5 |
| 3 | CNRM-CM3 | 1 | 1 | 1 |
| 4 | CSIRO-MK3.0 | 1 | 1 | 1 |
| 5 | GFDL-CM2.0 | 1 | 1 | 1 |
| 6 | GFDL-CM2.1 | 1 | 1 | 1 |
| 7 | GISS-ER | 1 | 2, 4 | 1 |
| 8 | INM-CM3.0 | 1 | 1 | 1 |
| 9 | IPSL-CM4 | 1 | 1 | 1 |
| 10 | MIROC3.2(medres) | 1...3 | 1...3 | 1...3 |
| 11 | ECHO-G | 1...3 | 1...3 | 1...3 |
| 12 | ECHAM5/MPI-OM | 1...3 | 1...3 | 1...3 |
| 13 | MRI-CGCM2.3.2 | 1...5 | 1...5 | 1...5 |
| 14 | CCSM3 | 1...4 | 1...3, 5...7 | 1...7 |
| 15 | PCM | 1...4 | 1...4 | 2...3 |
| 16 | UKMO-HadCM3 | 1 | 1 | 1 |

## Change in mean-annual T (oC),2041-2070 from 1971-2000,middle change among 112 projections,       at every downscaled location

- Change in mean-annual T (oC),2041-2070 from 1971-2000,*middle change among 112 projections,       at every downscaled location*

## Change in mean-annual P (in/yr),2041-2070 from 1971-2000,middle change among 112 projections,       at every downscaled location

- Change in mean-annual P (in/yr),2041-2070 from 1971-2000,*middle change among 112 projections,       at every downscaled location*

## Focusing on Bighorn area...

**1).**** From website, download monthly “****mean-area****” T****air**** & P time series for all 112 projections.**
**2).**** Compute historical-to-future period **_**changes**_** in mean-annual, mean-area T & P for every projection.  Use 1971-2000 as historical reference period.**

## 2010-2039			2040-2069		        2070-2099

- 2010-2039			2040-2069		        2070-2099

## Now consider spread of paired changes... yellow-area shows intersected 10/90 percentile ranges

- Now consider spread of *paired* changes... yellow-area shows intersected 10/90 percentile ranges

- 2010-2039			2040-2069		        2070-2099

## Consider spread of paired changes in T and P 

- Consider spread of *paired* changes in T and P

- 2010-2039			2040-2069		        2070-2099

## Consider spread of paired changes in T and P 

- Consider spread of *paired* changes in T and P

- 2010-2039			2040-2069		        2070-2099

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent “climate projections”?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

## Potential Natural Impacts

- Based only on warming...
- less snowfall, more rainfall 
- less snowpack, more runoff during winter 
- less snowpack, less runoff during spring 
- less snow area, more watershed participating in winter runoff events relevant to local flood control
- earlier greenup, longer growing seasons
- increased crop water demand based on T increase
- But, not sure whether CO2 increases will counter/amplify
- warmer aquatic environments

## Projected Runoff Impacts...“nearby” basin (Upper Missouri)

- Reclamation R&D study (FY08, ongoing)
- Collaboration with Univ CO, Univ AZ, NWS Missouri Basin RFC and Colorado Basin RFC

## Missouri above Toston:Change in Annual T-Norms

## Missouri above Toston: Change in Annual P-Norms

## Missouri above Toston: Change in Annual Flow-Norms

## Missouri above Toston: Change in Monthly T-Norms

## Missouri above Toston: Change in Monthly P-Norms

## Missouri above Toston: Change in Monthly Flow-Norms

## Potential Operations Impacts

- Less “controllable” water supply if...
- Increased winter runoff (decreased spring runoff) combined with no reduction in winter flood-space causes winter runoff to be spilled rather than conserved
- Different release schedules to accommodate...
- earlier greenup, longer growing seasons
- Changes in crop water demand
- Management of aquatic environments under warming
- Others?

## Outline	

- Is climate changing?
- Are we affecting it?
- Can we predict it?
- Recent “climate projections”?
- Impacts to hydrology and operations?
- Factoring it into longer-term planning?

## Some scoping questions for factoring climate change into planning analyses... Reclamation has recent experience with Options 3 and 4

**No**

**START**

- Question 7)
- Should effects disclosure
- be based on projected
- climate change?

**Option 4:**
- Quantitative Sensitivity Analysis...

**Option 5:**
- Quantitative Effects Analysis, where disclosure is based on a
- projected climate scenario rather than continued recent climate

**Option 1:**
**N**o Analysis

- Question 6)
- Is look-ahead more  than
- ~15 to 20 years?

- Significant Sensitivity?

- Question 1)
- Is climate relevant to the
- proposed project?

- Question 2)
- Is look-ahead relevant
- on a climate change
- time scale?

- Question 3)
- Are regional projections
- of climate change
- available?

**Option 2:**
- Literature Review...

- Question 4)
- Do regional projections
- suggest significant
- change?

- Question 5)
- Is it preferable to
- follow lead of partner
- agency?

**No**

**No**

**Yes**

**Yes**

**Yes**

- IPCC 2007:  (a) _climate_ is generally assessed over a 20- to 30-year period; (b) _climate change_ is generally measured as statistical changes between periods of 10 years or longer. (http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_Annexes.pdf)

**Option 3:**
- Qualitative Analysis...

**Option 6:**
- Follow lead of
- Partner-Agency

**END**

- Options 4 and 5 include the same Literature Review as in Option 3.

**No**

**No**

**Don’t Know**

**No**

**Yes**

**Yes**

**Yes**

**Yes**

**No**

**Yes**

**All Regions, TSC**

**MP, PN, TSC**

## Analyzing Operations under Climate Change(Option 4 example, MP OCAP/ESA study)

- Natural Responses, Social Responses, Operational Constraints

- Operations Response

- Operations-dependent Response

*“**Bracketing” climate projections...*

- Analyzing Operations under Climate Change(Option 4 example, MP OCAP/ESA study)

*Rainfall-runoff simulation analysis under each climate projection..*.

*Operations modeling followed, reflecting supply changes under each projection. Delta levels, Delta water quality, and reservoir water temperature modeling*

*Consumptive Use modeling wasn’t done*... *choice was rationalized assuming that demands wouldn’t necessarily change at “district-level” given management flexibility.*

*No operations constraint adjustments made (e.g., monthly flood control rules, environmental/instream demands)*

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Climate Projection Selection:Rationale developed for MP OCAP

- Given:  available downscaled projections
- http://gdo-dcp.ucllnl.org/downscaled_cmip3_projections/
- We don’t know the “right” projections, therefore consider all CMIP3 projections as fair game.
- We cannot classify emissions paths as more/less likely.
- Its not obvious how to classify GCMs as better/worse.
- Gleckler et al. 2008, Reichler et al. 2008, Brekke et al. 2008
- Projections uncertainty doesn’t necessarily diminish after determining a “worse” set of GCMs and discarding their projections.
- Brekke et al. 2008

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Projection Selection Factors

- Periods:  Future and historical (planning look-ahead determines *future*)
- Climate Metric:  for assessing “change” relevant to study (computed for all projections)
- Location:  where “spread” of changes from all projections is assessed, relevant to study
- Change Range:  subjective, within “spread”

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Projection Selection Factors:MP OCAP Choices

- Periods:  1971-2000, 2011-2040 (consultation horizon is through 2030)
- Climate Metric:  Period Mean-Annual Tair & P
- Location:  “Above Folsom” (sensitivity interest on change in water supply, Sierra Nev. runoff)
- Change Range:  10 to 90 %-tile Tair, P (desire to represent broad set of possibilities)

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Implementing Selection Factors:Step 1) Survey projections “Above Folsom”

- Implementing Selection Factors:Step 1) Survey projections “Above Folsom”

**1a.**** From website, download monthly T****air**** & P time series.**
**1b.**** Compute historical and future period “climate metrics” for every projection.**
**1c. ****Compute historical-to-future period **_**changes**_** in “climate metric” for every projection.**

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices, Appendix R

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Step 3)  Overlay rank-threshold Tair and P on scatter paired changes 

- Step 3)  Overlay rank-threshold Tair and P on scatter paired changes

- _[http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices](http://www.usbr.gov/mp/cvo/ocapBA_2008.html#appendices)__, Appendix R_

## Result:  range of future climates represented by set of bracketing projections

**Result**:  range of future climates represented by set of bracketing projections

## Questions?

- Levi Brekke
- Reclamation, Technical Service Center
- lbrekke@do.usbr.gov