Western Water Supply

Kevin Werner, Andrew Murray, WR/SSD Jay Breidenbach, WFO Boise Cass Goodman, Steve Shumate, CBRFC Alan Takamoto, Scott Staggs, CNRFC Don Laurine, NWRFC Chad Kahler, WFO Tucson

Outline

 Western Water Supply 

History

 Project overview  

Westwide map Forecast evolution



Verification



Ensemble services

 Future enhancements  

Climate variability and change Short range ensembles services

Western Water Supply Forecasts

 Forecasts for spring runoff amounts from snow melt dominated basins in western US  Routinely produced at 6 RFCs and coordinated with other agencies (NRCS and California DWR)  NWS forecast program began in 1940s  Primary forecast tools: 

Ensemble Streamflow Prediction



Multivariate Linear Regression

Legacy Water Supply Forecast Product (Credit: NRCS / NOAA

)

  

Project in a Nutshell

Goals:   

A “one stop shop” for NWS water information at the seasonal timescale Consistent presentation of products between RFCs Harness collective innovation from multiple offices

Users: 

Existing Water Supply forecast users



Strong support from USBR and state water resources agencies for examples

 

Groups with cross basin interests (e.g. media, power companies) NWS internal users

Major Components:  

Map: Single map for all western WS forecasts from 6 RFCs Forecast evolution: Plotting capability to show evolution of current year forecast and observed river flow

 

Verification: Forecast evaluation from past forecasts and forecast tools Ensemble services: Interaction capability with ensemble streamflow predication

Project in a Nutshell (con’t)

  Milestones (past):     

April 2005: Working group formed, planning meeting held January 2006: Initial website launched September 2006: Included AB, WG, and MB RFCs in development January 2007: Common database developed March 2007: Launched outreach effort and included SHs

Milestones (future):      

August 2007: Launch verification 1.0 capabilities September 2007: Move software to NWRFC web farm October 2007: Launch forecast evolution 2.0

October 2007: Launch ensemble services 1.0

January 2008: Integrate WGRFC data 2008?: Integrate climate change capabilities

Map

 www.cbrfc.noaa.gov/westernwater  “One Stop Shop” for NWS water supply forecasts  Flexible and consistent map presence across western USA  Zoomable to basin scale  Mouse over capability for forecast values

Forecast Evolution

 Evolution of current year forecast and observed streamflow  Options to include: 

Normal streamflow volume

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Forecast window



Forecast accumulation

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Accumulated Observed, etc…

  Originally developed at NWRFC Version 2.0 contract development work proceeding 

Add ESP forecasts



Add interactive features

Forecast Verification

 Goal: Provide users of all types with forecast verification information 

Easy to understand



Meaningful

 

Accessible from forecasts Dynamically generated plots from database Data Visualization



MAE, RMSE, etc

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Conditional on Lead time, year

Error

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Skill relative to Climatology



Conditional

Skill Categorical

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Traditional (NWS) verification including FAR and POD

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Category definitions tied to climatology values (e.g. mean flow, terciles, etc.) or user definable

Plot credit: Chad Kahler

Ensemble Services

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Goals:



Intuitive user interface for current ensemble forecast



Access to archived streamflow data for perspective

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Dynamic, flexible plots

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Access to underlying data and database



Climate change scenarios

Climate Change

 Latest IPCC report confirms “temperatures averaged over all habitable continents … will very likely rise at greater than the global average rate in the next 50 years and by an amount substantially in excess of natural variability.” (IPCC WR1, 2007) Source: IPCC, 2007

Trends in 1 Apr SWE over the 1960–2002 (left) and 1950-1997 (right) periods of record directly from snow course observations from Mote (2006) and Mote et al. (2005) respectively.

Extend NWS Product Suite?

Years Climate Change based run off scenarios?

 Current product suite covers hours to seasons;  Should we consider climate change scenarios and build multi-year products for run-off, temperature, precipitation?

 User requirements from power companies, USBR, etc for climate change scenarios

Water Supply with Climate Change

 Many in water community are asking for it  Idea: Provide scenario based water supply outlooks in the context of historical data and current season forecasts 

Include uncertainty

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Temperature, precipitation, and/or lead time based scenarios

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Ultimately link scenarios to atmospheric carbon based scenarios

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Leverage historical simulation capabilities in ESP

Leveraging ESP for long range scenarios

 Multiple “historical simulation” runs: 

Use historical basin temperature and precipitation time series

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Build ensemble by repeatedly shifting year order by one

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Incorporate scenarios through additive (temperature) or multiplicative (precipitation) year-wise adjustments

ENSEMBLE FORECAST SERVICES

Forecast Point: Columbia River at the Dalles Dam

Archive O Normal Runoff O Model Normal O Historical Year(s) Current Forecast O Ensemble Streamflow Prediction O Ensemble members by forcing year(s) O Ensemble members by ENSO Climate Change O Year (slider bar 2010 2050) O Temperature (slider bar -5 F - +5 F) O Carbon Scenario Options O Accumulate over period O Plot Type (box and whisker, bar, lines, etc.) O Data O Plot interval (set axes limits)

Summary

 Western Water Supply 

History



Current capabilities

 Coming enhancements 

Verification



Water Supply ensemble services

 Climate Change

Thank You

[email protected]