nws river forecast system evolves to chps scott lindsey development and operations hydrologist,...

NWS River NWS River Forecast SystemForecast System

Evolves to Evolves to CHPSCHPS

Scott Lindsey

Development and Operations Hydrologist,

Alaska-Pacific River Forecast Center

NOAA/National Weather Service

30 October 2009

30 October 200930 October 2009 NWSRFS Evolves to CHPSNWSRFS Evolves to CHPS 22

TopicsTopics

National Weather Service River Forecast System (NWSRFS) Introduction

Snow modeling within NWSRFS Rainfall Runoff modeling within NWSRFS Transition to Community Hydrologic Prediction System

(CHPS) – What is it and what does it mean for the research community?


National Weather Service National Weather Service River Forecast System (NWSRFS)River Forecast System (NWSRFS)

Is the heart of today’s river forecasting mission Composed of subsystems for

Deterministic operational forecasting Ensemble streamflow prediction Model calibration Forecast verification

Contains Hydrologic and hydraulic models Data preparation and manipulation modules Interactive display for river forecasters Model set-up and calibration

Uses basin-based computational domain


Functions of NWSRFSFunctions of NWSRFS

Operational

Forecast system

Hydrologic Operations

Calibration System

Ensemble Streamflow Prediction System

Verification System


System was cutting edge architecture in the 1970s Developed for use on mainframe computers Computer real memory constrained Performance required highly customized database Implemented in Fortran IV Modular in the sense of having being able to put together

different models to simulate different hydrologic situations Difficult to add new models and techniques Collaboration and research to operations was inhibited

1970s 1980s 1990s 2000s 2003 today1970s 1980s 1990s 2000s 2003 today

NWSRFS IntroductionNWSRFS Introduction


Calibration System

HistoricalData

Real-timeDataObserved& Projected

HydrometAnalysis

Observed & Predicted Values

Historical Data AnalysisAreal Time Series

Model Calibration

Parameters

Hydrologic/HydraulicModels

Short Term Forecast

Current States

Hydrologic/HydraulicModels

now time

window

flo

w

Probabalistic Products

Deterministic Products Verification

Software

Verification Data/Graphics

ArchivedData Observed and Forecast

Verification System

NWSRFS SchematicNWSRFS Schematic

Operational System

Ensemble Streamflow Prediction


Hydrologic Modeling in NWSRFS

Snow and Glaciers Rainfall/Runoff Soil Moisture Accounting Routing

River ForecastingRiver Forecasting


Snow Accumulation/Ablation Snow Accumulation/Ablation modelingmodeling

APRFC uses the Snow-17 model in NWSRFS Conceptual model using air temperature as the sole index to determine the energy exchange across the snow-air interface Precipitation is the only other required input variable SNOW-17 was primarily designed for use in river forecasting. This means that the model needs to use data that are readily available everywhere, both historical climatological data for calibration and real time data for operational applications. Calibrated by adjusting model parameters such as the melt factors, areal depletion curves, and the snow correction factor to tune the volume and timing of the snowmelt. Good documentation available at http://earth.boisestate.edu/home/jmcnamar/hydro09/Readings/snow17.pdf


Anderson, 2006


Summary of Snow Model ParametersSummary of Snow Model Parameters

The SNOW-17 model has 12 parameters. This counts the areal depletion curve as one parameter though it is input as a series of 9 values used to define the shape of the curve. Some of the parameters have more influence on the simulation results than others. The most influential, or major parameters, are those that typically have to be determined through calibration even though some guidelines are available to obtain initial estimates [Anderson (2002)].

The others, the minor parameters, typically can be assigned values based on the climatological conditions at the location being modeled. These parameters have a much smaller effect, in general, on the results and seldom need to be altered from their initially assigned value. There are no parameters associated with the snow depth computations in SNOW-17. There are several potential parameters, but all of these have been set to a fixed value based on comparisons of simulated versus observed snow depth and water equivalent at selected locations that had quality observations of both quantities.


1. SCF - The multiplying factor which adjusts precipitation that is determined to be in the form of snow. SCF primarily accounts for gage catch deficiencies, but also implicitly includes the net effect of vapor transfer (sublimation and condensation, including from intercepted and blowing snow) and transfers across areal divides.2. MFMAX - Maximum melt factor during non-rain periods – assumed to occur on June 21st (mm·°C-1· 6 hr-1). 3. MFMIN - Minimum melt factor during non-rain periods – assumed to occur on December 21st (mm·°C-1· 6 hr-1).4. UADJ - The average wind function during rain-on-snow periods. UADJ is only a major parameter when there are fairly frequent rain-on-snow events with relatively warm temperatures.5. SI - The mean areal water equivalent above which there is always 100 percent areal snow cover (mm). SI is not a major parameter when the model is applied at a point location or when significant bare ground appears soon after melt begins no matter the magnitude of the snow cover.6. Areal Depletion Curve – Curve that defines the areal extent of the snow cover as a function of how much of the original snow cover remains after significant bare ground shows up. The areal depletion curve also implicitly accounts for the reduction in the mean areal melt rate that occurs as less of the area is covered by snow. Generally not needed for a point location.

The major parameters for the SNOW-17 model are:The major parameters for the SNOW-17 model are:


1. NMF - Maximum negative melt factor (mm·°C-1·6 hr-1). The negative melt factor has the same seasonal variation as the non-rain melt factor, thus the maximum value is assumed to occur on June 21st. 2. TIPM - Antecedent temperature index parameter (real – range is 0.01 to 1.0). Controls how much weight is put on temperatures from previous time intervals when computing ATI. The smaller the value of TIPM, the more previous time intervals are weighted.3. PXTEMP - The temperature that separates rain from snow (°C). If the air temperature is less than or equal to PXTEMP, the precipitation is assumed to be in the form of snow. The PXTEMP parameter, as defined for SNOW-17, is not used if a rain-snow elevation time series is used to determine the form of precipitation.4. MBASE - Base temperature for snowmelt computations during non-rain periods (°C). Typically a value of 0°C is used.5. PLWHC - Percent liquid water holding capacity (decimal fraction). Indicates the maximum amount of liquid water, as a fraction of the ice portion of the snow, that can be held against gravity drainage (maximum allowed value is 0.4).6. DAYGM - Constant daily amount of melt which takes place at the snow-soil interface whenever there is a snow cover (mm·day-1).

The minor parameters for the SNOW-17 model are:The minor parameters for the SNOW-17 model are:


Anderson, 2006


Rainfall-Runoff modelingRainfall-Runoff modeling APRFC uses the Sacramento Soil Moisture Accounting (SAC-SMA) model Spatially-lumped continuous soil moisture accounting model Ideal model for the simulation of large-scale (>1000 km2) basins Takes mean precipitation, evaporation and temperature as input Calibrated by adjusting baseflow, tension water capacities and runoff simulation parameters Calibration input includes point or areal estimates of historical precipitation, temperature, and potential evaporation Documentation at http://www.nws.noaa.gov/oh/hrl/nwsrfs/users_manual/part2/_pdf/23sacsma.pdf

How the SacramentoHow the SacramentoModel Works Model Works

Each basin is represented vertically by two zones: An upper zone (short- term storage capacity) A lower zone (bulk of the soil moisture and longer

groundwater storage) Tension water elements (water bound by adhesion

and cohesion, extracted only by evapotranspiration) Free water elements (free to move under

gravitational forces, may be depleted by evapotranspiration, percolation, horizontal flow)

Sacramento Model ParametersSacramento Model Parameters

http://www.crh.noaa.gov/ncrfc/doc/calibration/flowing.html


Interactive Hydrologic ToolsInteractive Hydrologic Tools


Shortcomings of NWSRFSShortcomings of NWSRFS

Current snow model is a temperature index model, not an energy balance.

Scale of inputs: Lumped inputs from point data applied over basins ranging from 300 to 25000 km2

Ability to incorporate modeling advances (distributed models, new snow and soil moisture models) is inhibited by system design (originally for a main frame).


Stimulus for ModernizationStimulus for Modernization New NOAA Hydrology Program initiatives

Nationally consistent gridded water resources forecasts delivered to customers for critical decisions

Probabilistic river forecasts at all time scales Verification extended to probabilistic forecasts

Better research-to-operations pathway Easier, faster, cheaper

Increase collaboration with federal, academic, public, private, and international partners Share data and models more effectively

Increase capabilities to modify/expand services


CHPS ProjectCHPS Project CHPS is the NWS’s Community Hydrologic Prediction

System CHPS will replace NWSRFS CHPS is built using framework delivered by the product,

“Delft-FEWS”, from Deltares in The Netherlands CHPS

Highly modular and configurable Based on Service Oriented Architecture (SOA) principles Allows easy addition of new models and techniques Promotes streamlined research to operations Allows greater collaboration with NOAA’s hydrology partners

(e.g., USACE, USGS, etc.)

1.1. What’s the difference between What’s the difference between CHPS and FEWS?CHPS and FEWS?

Flood Early Warning System (FEWS) is a suite of infrastructure software maintained and supported by Deltares. Only when FEWS is configured for the user’s specific domain does it transform into a functioning system. A user would supply the necessary modeling operations, or acquire them from a source which shares (open source) or sells FEWS-compatible models.

Community Hydrologic Prediction System (CHPS) is NOAA’s customized application of FEWS. CHPS runs models that are compatible with FEWS - including those migrated from NWSRFS – providing extra user capabilities not available via FEWS, such as model calibration. In the future, NOAA will make CHPS models available to other FEWS users.



CHPS TerminologyCHPS Terminology

FEWS

FEWS features have potential application to the entire FEWS user community (generic time-series storage, displays, workflows, etc.)

FEWS is a suite of configurable modules which can store, manipulate, and display time series data using your own and community applications.

CHPS is a uniquely configured realization of FEWS, using RFC-specific data and applications.

Other FEWS-based systems (e.g., NFFS) are different realizations of FEWS.

Community applications

shared with other FEWS users

Applications, configuration

s, data, unique to

CHPS


CHPS Implementation StrategyCHPS Implementation Strategy

Port NWSRFS models that require calibration Hydrologic/Hydraulic Models Soil Moisture Models Snow Models Reservoir Models(BASEFLOW, SARROUTE, CONS_USE, LAG/K, LAY-COEF, TATUM,MUSKROUT, RES-J, RSNWELEV, SNOW-17, CHANLOSS,STAGE-Q, SSARRESV, UNIT-HG, RES-SNGL, SAC-SMA)

Create FEWS adapters for external models (e.g., HEC-RAS and ResSim from USACE)

(2003) 2006 2007 2008 2009 2010 2011(2003) 2006 2007 2008 2009 2010 2011


Develop forecaster “MODs” capability in FEWS “MODs” give forecaster ability to adjust model inputs and

parameters in during forecast runs Deltares building new “MODs” capability and interface into

FEWS infrastructure for all customers by working closely with RFC personnel

Can modify model states, input data, & parameters (see NWSRFS list:

(IGNORETS, FMAP, SSARREG, MFC, RRICHNG, SWITCHTS, TSCHNG, CHGBLEND, WECHNG, RAINSNOW, RRIMULT, WEADD, TSADD, SACCO, AESCHNG, ROMULT, SETMSNG, UADJ, ROCHNG, UHGCHNG, SETQMEAN, UHGDATE, QCSHIFT, QPSHIFT, HECRAS, etc.)

(2003) 2006 2007 2008 2009 2010 2011(2003) 2006 2007 2008 2009 2010 2011

CHPS Implementation StrategyCHPS Implementation Strategy


The FEWS AdapterThe FEWS Adapter

A key feature of DELFT-FEWS is its ability to run external modules to provide essential forecasting functionality. The General Adapter is the part of the DELFT-FEWS system that implements this feature. It is responsible for the data exchange with these modules and for executing the modules and their adapters.


Development of FEWS AdapterDevelopment of FEWS Adapter


Models linked to Delft-FEWSModels linked to Delft-FEWS The table below gives an overview of the models linked via the Published Interface to the Delft-Fews system. For these models, a model

adapter is available. Please note that adapters that have not been developed by Deltares cannot be used without permission of the owner. All models indicated in bold typeface are running in operational systems.

Model Type Supplier/Owner Country ISIS Hydrodynamic HR/Halcrow UK PDM Rainfall-Runoff CEH UK TCM Rainfall-Runoff CEH UK KW Routing (kinematic wave) CEH UK PACK Snow Melt CEH UK ARMA Error Correction CEH UK PRTF Event Based RR PlanB UK PCRASTER Dynamic Modelling Software Univ. Utrecht Netherlands TRITON Surge propagation/Overtopping PlanB UK TWAM 2D Hydrodynamics PlanB UK STF Transfer functions EA UK DODO Routing (layered Muskingum) EA UK MCRM Rainfall-Runoff EA UK Modflow96/VKD 3D groundwater Deltares/Adam

Netherlands/UK Taylor

Mike11 Hydrodynamics DHI Denmark


Models linked to Delft-Fews (cont.)Models linked to Delft-Fews (cont.)

Model Type Supplier/Owner Country NAM Rainfall-Runoff DHI Denmark TOPKAPI Rainfall-Runoff Univ. of Bologna Italy HBV Rainfall-Runoff (inc SHMI Sweden

snowmelt) Vflo Distributed Rainfall-Runoff Vieux & Associates USA SWMM Urban Rainfall-Runoff USGS USA HEC-RAS Hydrodynamic USACE USA HEC-ResSim Reservoir Simulation USACE USA Snow17 Snow Melt NWS USA SAC-SMA Rainfall-Runoff NWS USA Unit-HG Unit-Hydrograph NWS USA LAG/K Routing (hydrological) NWS USA SARROUTE Routing (hydrological) NWS USA SSARRESV Reservoir Simulation NWS USA RESSNGL Reservoir Simulation NWS USA BASEFLOW Baseflow Simulation NWS USA


Models linked to Delft-Fews (cont.)Models linked to Delft-Fews (cont.)Model Type Supplier/Owner Country

CHANLOSS Channel loss Simulation NWS USA APICONT Rainfall-Runoff NWS USA CONSUSE Consumptive use of River NWS USA

Simulation GLACIER Glacier simulation NWS USA LAYCOEF Routing Model NWS USA MUSKROUT Routing Model NWS USA RSNELEV Rain Snow Elevation NWS USA

Simulation SACSMA-HT Rainfall-Runoff (Heat NWS USA

Transfer) LAYCOEF Routing Model NWS USA TATUM Routing Model NWS USA rtcModule Reservoir Simulation Deltares Netherlands PRMS Rainfall-Runoff Univ. of Karlsruhre Germany SynHP Hydrodynamics BfG Germany SOBEK Hydrodynamics, Water Deltares Netherlands

Quality, RR


Models linked to Delft-Fews (cont.)Models linked to Delft-Fews (cont.)

Model Type Supplier/Owner Country SOBEK-2d Linked 1d/2d inundation Deltares Netherlands

modeling DELFT-3D 2D-3D Hydrodynamics Deltares Netherlands Sacramento Rainfall-Runoff Deltares Netherlands RIBASIM Water distribution Deltares Netherlands + Reservoir REW Distributed Rainfall-Runoff Deltares Netherlands DELFT3D 2/3D Hydrodynamics/ Deltares Netherlands

Water quality Flux 1D Hydrodynamics Scietec Austria URBS rainfall-runoff and Don Caroll Australia

hydrological routing Grid2Grid Distributed Hydrologic CEH UK

Model Het Wageningen Rainfall-Runoff Haskoning Netherlands Model


SummarySummary

Hydrologic Modeling at the River Forecast Center has been in a “remodeling” phase for many years (porting NWSRFS from Mainframe to IBM RISC to HP UNIX to LINUX).

Now we are in a “new construction” phase that should allow us to take much better advantage of the advances in research, technology and modeling.

We plan to keep UAF modelers in the loop and hope to apply your expertise to the real-time hydrologic forecasting challenges here in Alaska


Questions???

nws river forecast system evolves to chps scott lindsey development and operations hydrologist,...

Documents

nwsrfs snow

nwsrfs introduction

nwsrfs transition

nwsrfs conceptual model

nws river forecast system

chps5 system

model parameters

real time data