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Global Model Development Priorities

Presented By: Hendrik Tolman & Vijay Tallapragada (NWS/NCEP)Contributors: GCWMB (EMC), NGGPS (NWS)

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Operational System Attribute(s)

System Name Acronym Areal Coverage

Horz Res

Cycle Freq

Fcst Length

(hr)

Global Forecast System GFS Global T1534L 13 km

4 0-240

T574L 35 km

4 240-384

System Attributes

GFS Global GFS Hybrid 3D-VAR Ensemble Kalman Filter (EnKF) Data Assimilation (see Derber & Whitaker)

SST Real-Time Global Sea Surface Temperature (RTG-SST) & 1982-2012 5 minute SST climatology

Ice IMS ice analysis from National Ice Center & 1982-2012 30 minute sea ice concentration climatology

Land 27 km (T574) Global Land Data Assimilation (GLDAS) Climatology

Aerosols NEMS GFS Aerosol Component (NGAC)

System Data Assimilation or Initialization Technique

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Why System(s) are Operational

Primary stakeholders and requirement drivers• National Weather Service Operations, Various customers in the Public, Private,

Academic and International organizations.• Majority of the NCEP Production Suite (downstream) depends on GFS forcing

What products are the models contributing to?• Atmospheric variables at standard pressure levels and surface• Several post-processed fields

What product aspects are you trying to improve with your development plans? • Wide range of forecast products including 500 hPa Geopotential Height Anomaly

Correlation Coefficients

Top 3 System Performance Strengths• Timeliness• Reliability• Accuracy

Top 3 System Performance Challenges • More details in the NGGPS, NEMS, Nesting, GDAS Presentations• Development and implementation of Unified Coupled Global Modeling System for

GFS, GEFS and CFS

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System Evolution Over the Next 5 Years

Major forcing factors• NGGPS• Scientific advancements, Computational Resources & System Engineering

Science and development priorities• Continuous improvements in Data Assimilation and Physics in GFS• NGGPS: unified global forecast system operating at convective resolving scales• Unification of weekly, monthly, and seasonal forecasts

What are you top challenges to evolving the system(s) to meet stakeholder requirements?

• Computational resources and efficiency• Retrospective and Reforecast Requirements• Tighter implementation schedules for model/DA upgrades• NEMS Readiness• O2R2O2R….

Potential opportunities for simplification going forward• NGGPS: Development of Unified Coupled Global Modeling System including

atmosphere, land, ocean, ice, wave, aerosol, chemistry, ionosphere (WAM) components using NEMS infrastructure

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Top 3 Things You Need From the UMAC

1. Endorsement of plan to continue to unify modeling superstructure and infrastructure under NOAA Environmental Modeling System and companion software infrastructure

2. Suggestions for improved O2R and R2O strategies

3. Optimal strategies for bridging the gap between high-resolution mesoscale models and the global model