Climate Prediction Applications Science Workshop Jim Noel Senior

Climate Prediction Applications Science Workshop Jim Noel Senior Hydrologist NOAA/ National Weather Service Ohio River Forecast Center March 4, 2008 1 Climate Prediction Applications Science Workshop National Weather Service

Outline • History of Flood Outlooks • Why change now? • Ensemble Streamflow Prediction (ESP) • Climate Forecasts within ESP • Experimental Water Resources Outlooks • Expansion of Climate Products – Examples • Summary 2 Climate Prediction Applications Science Workshop National Weather Service

History • Based on series of text products • Subjective in nature • Only produced in flood season • Not a continuous water watch for high and low flows From Hydrologic Information Center – April 14, 2006 3 Climate Prediction Applications Science Workshop National Weather Service

Why Change Now? • Need for continuous water watch • Need to collaborate with our partners more • Technology advances allow us to provide more useful information • Innovate or dissipate 4 Climate Prediction Applications Science Workshop National Weather Service

Ensemble Streamflow Prediction • River Forecast Centers capture soil moisture using SAC-SMA (Sacramento) hydrologic soil moisture accounting model and capture snow using SNOW 17 model • Good estimations of soil moisture and snow pack water contents are critical to accurate hydrology (RFCs) and meteorology and climate (NCEP) forecasts. • To get good soil moisture estimations requires good precipitation inputs 5 Climate Prediction Applications Science Workshop National Weather Service

Ensemble Streamflow Prediction Manual Calibration Program (MCP) Operational Forecast System (OFS) Ensemble Streamflow Prediction (ESP) MCP OFS ESP 6 Climate Prediction Applications Science Workshop National Weather Service

Ensemble Streamflow Prediction • Ensemble Streamflow RFC NWSRFS/ESP/Probabilistic Prediction (ESP) necessary component used to take short range deterministic SAC-SMA model into short term climate predictions of rivers • Similar in concept to the ensembling approach used for atmospheric modeling 7 Advanced Hydrologic Prediction Service Climate Prediction Applications Science Workshop National Weather Service

Ensemble Streamflow Prediction Multiple streamflow scenarios with historic meteorological or forecast weather/climatic data Flow Possible scenarios Scenario 2 Scenario 1 Scenario 3 Saved model states reflect current conditions Time Results used in statistical analysis to produce forecasts with probabilistic values 8 Climate Prediction Applications Science Workshop ©The COMET Program National Weather Service

Ensemble Streamflow Prediction Now Future Medium chance of this level flow or higher Flow Past Low chance of this level flow or higher High chance of this level flow or higher Time 9 Climate Prediction Applications Science Workshop ©The COMET Program National Weather Service

Climate Forecasts Within ESP Pre Adjustment Technique Weight/Modify on Input Side 71 72 73 74 75 Post Adjustment Technique Weight On Output Side 10 Climate Prediction Applications Science Workshop National Weather Service

Climate Forecasts Within ESP Historical MAT and MAP Adjustment System Weather Forecasts Adjusted Historical MAP and MAT Climate Forecasts 11 Climate Prediction Applications Science Workshop National Weather Service

Climate Forecasts Within ESP Long range seasonal water supply Spring snowmelt volume forecasts Spring snowmelt peaks Minimum flows for navigation, irrigation, environmental, recreation, etc Water Resources Outlooks 12 Climate Prediction Applications Science Workshop National Weather Service

Climate Forecasts within ESP • 90 -day probability of exceedance • Blue line is an historical simulation based on climatology • Black line is the conditional simulation with CPC inputs • Conditional simulation based on CPC inputs yield lower potential for flooding and high flows. 13 Climate Prediction Applications Science Workshop National Weather Service

Water Resources Outlooks • Water Resources Outlook • Uses NWSRFS SACSMA and ESP • Uses HPC/CPC Outlooks • Can generate a whole host of products • An experimental product of NOAA/NWS • Being develop for the 30 to 90 day period 14 Climate Prediction Applications Science Workshop National Weather Service

Water Resources Outlooks • Partner with USGS/USACE • Utilize USGS streamflow percentiles • Verify product based on USGS 28 -day mean flows • Experimental has ended, waiting for operational approval • GOAL: Slowly expand nationwide 15 Climate Prediction Applications Science Workshop National Weather Service

Water Resources Outlooks • Based on basins and point forecasts • 159 of 266 OHRFC points have 30, 60 and 90 day expected streamflows • 20 more USGS points could be used but incomplete data 16 Climate Prediction Applications Science Workshop National Weather Service

Water Resources Outlooks 30 -day Verification August 2006 through January 2008 • POD above normal flows = 0. 78 • FAR above normal flows = 0. 30 • POD below normal flows = 0. 65 • FAR below normal flows = 0. 09 • Percent of forecast basins in correct category = 78% 17 Climate Prediction Applications Science Workshop National Weather Service

Water Resources Outlook Other Approaches • Use analog years (year weighting technique in ESP (Post-Adjustment) based on atmospheric and oceanic response (ENSO/NAO etc) • Run ESP with CPC outlooks and analog years approach • Research on this is being done by OHRFC and hopefully Michigan Tech 18 Climate Prediction Applications Science Workshop National Weather Service

Expansion of Climate Products - Examples • Probability of reaching flood stage • Uses NWSRFS SAC-SMA and ESP • Generated at NCRFC for minor, moderate and major flooding • An experimental product of NOAA/NWS • Being expanded at other RFCs 19 Climate Prediction Applications Science Workshop National Weather Service

Expansion of Climate Products - Examples • Link WRO for each of our points to probability function images • Allow customers to drill down into the WRO further • Allow customers to modify risks based on ENSO as a starting point • This work is being driven by NWS Western Region 20 Climate Prediction Applications Science Workshop National Weather Service

Summary • Technology (ESP) has advanced to allow subjective text based flood outlooks to be replaced by a more objective based water resources outlook • Climate forecasts are integrated into hydrologic forecasts mostly through adjustments to the inputs in the Ensemble Streamflow Prediction • Water Resources Outlooks would provide a continuous water watch for streamflows in the 1 -90 day period for expected flows • Water Resources Outlooks would not only be for high flows but ALL flows 21 Climate Prediction Applications Science Workshop National Weather Service

Summary • Streamflow categories are based on USGS percentile categories • Verification is based on USGS data • Designed to promote NWS/USGS/COE and help us and other partners and customers in their missions! • The climate products can be used in providing necessary information on flood and drought potential during the coming months. 22 Climate Prediction Applications Science Workshop National Weather Service