Recent performance statistics for AMPS real-time forecasts
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Transcript of Recent performance statistics for AMPS real-time forecasts
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Recent performance statistics for AMPS real-time forecasts
Kevin W. Manning–
National Center for Atmospheric ResearchNCAR Earth System Laboratory
Mesoscale and Microscale Meteorology DivisionBoulder, CO
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NCAR is sponsored by the National Science Foundation
–AMPS is sponsored by the NSF Office of Polar Programs
and theNSF UCAR and Lower Atmosphere Facilities Oversight Section
–Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
02-03 Nov 2011, Columbus, OH
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AMPS real-time forecasts• 6 two-way interactive grids:
– 45-km / 15-km grids to 120 forecast hours– 5-km / 1.67-km grids to 36 forecast hours
• Initial conditions– GFS 0.5-degree analyes used as first guess for WRFDA 3D variational data assimilation step
(domains 1 and 2)– Sea-ice conditions from near real-time SSM/I daily global ice concentration (NSIDC) (25-km grid)
• Domain 1 boundary conditions– GFS 0.5-degree forecast updated at 6-hour intervals
• WRF options– 44 vertical levels; lowest half level ~ 12 m above surface; 12 layers below ~1 km above surface– Microphysics: WSM 5-class scheme– LW Radiation: RRTMG– SW Radiation: Goddard SW scheme– Surface Layer Physics: Monin-Obukhov (Janjic Eta) scheme– Land Surface: Noah Land-surface model; 4 subsurface layers– PBL Physics: MYJ (Eta) TKE scheme
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
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AMPS statistics – Summertime Surface
• Nov-Dec-Jan 2010/2011 season– Temperature– Pressure– Wind
• Surface station reports– From GTS– From University of Wisconsin – Antarctic Meteorological Research Center
(AMRC)• Three regions
– Ross Ice Shelf– East Antarctic plateau– East Antarctic coastal
• Older WRF version 3.0.1.1 with Polar modifications
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
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Summer T – Ross Ice Shelf
Mean Statistics -- ~ 15 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer T – East Antarctic Plateau
Mean Statistics ~ 6 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer T – East Antarctic Coastal
Mean Statistics -- ~10 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer P – Ross Ice Shelf
Mean Statistics -- ~ 15 Stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer P – East Antarctic Plateau
Mean Statistics -- ~ 6 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer P – East Antarctic Coastal
Mean Statistics -- ~10 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer Wind Speed – Ross Ice Shelf
Mean Statistics -- ~ 15 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer Wind Speed – East Antarctic Plateau
Mean Statistics -- ~ 6 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Summer Wind Speed – East Antarctic Coastal
Mean Statistics -- ~10 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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• Summertime Summary– Warm bias on plateau. Mixed temperature bias in other
regions.– Warming trend in East Antarctic plateau and Ross Ice Shelf
regions. Very little temperature trend for coastal stations.– Plateau stations show greatest temperature error growth
(RMSE) over 120 hours. Little temperature error growth (RMSE) for Ross Ice Shelf and coastal regions.
– Pressure statistics show high correlation in all three regions, but steady error (RMSE) growth.
– Low pressure bias increasing in time over Ross Ice Shelf.– Slight high wind-speed bias
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
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AMPS Behavior – Wintertime Surface
• May-Jun-Jul 2011• Newer WRF version 3.2.1 with Polar
Modifications
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
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Winter T -- Ross Ice Shelf region
Mean Statistics -- ~21 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter T -- East Antarctic Plateau
Mean Statistics – ~13 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter T -- East Antarctic Coastal
Mean Statistics -- ~15 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter P -- Ross Ice Shelf region
Mean Statistics -- ~21 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter P -- East Antarctic Plateau
Mean Statistics -- ~13 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter P -- East Antarctic Coastal
Mean Statistics -- ~15 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter Wind Speed -- Ross Ice Shelf region
Mean Statistics -- ~21 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
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Winter Wind Speed – East Antarctic Plateau
Mean Statistics -- ~13 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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Winter Wind Speed -- East Antarctic Coastal
Mean Statistics -- ~15 stations
BiasRMSECorrelation (-1.0 to 1.0)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
Forecast Hour (0 – 120)
Forecast Hour (0 – 120)
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• Wintertime summary– In each region, a mix of high and low temperature biases
– average bias near zero.– Over plateau, strong signal of initial condition warm bias
that the model quickly corrects.– Larger temperature error (RMSE) growth, larger reduction
of temperature correlation, than we saw in summer.– As in summer, pressure statistics show significant error
growth (RMSE)– High wind speed bias, more notable than in summer.
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF)
Model
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Subsurface Temperature Initialization
• BPRC Antarctic results differ from AMPS results– BPRC results show cold bias in summer over East Antarctic Plateau– AMPS results show warm bias in summer over East Antarctica Plateau
• One possibly significant difference in the AMPS and BPRC is the initialization of subsurface temperature fields– AMPS cycles the subsurface temperature from one forecast to the next
• High resolution details• In balance with WRF physics• Subject to model drift
– BPRC initializes subsurface temperature fields using a 40-year annual mean air temperature analysis at deep ice layers, and a 40-year monthly mean air temperature analysis at the shallowest subsurface layer• No spin-up required• Low resolution
• Could this account for the different results for forecasts of air temperature?
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Two experiments
• Cycled subsurface temperature fields (CYCLE)• Subsurface temperature fields initialized from
monthly mean and annual mean temperatures (MEANT)
• Two 72-hour forecasts per day, in the AMPS 45km/15km configuration, from 10 Jan through 06 Feb 2011 (about 4 weeks).– The CYCLE conditions have been spun up for about 6
weeks, starting from AMPS real-time fields (i.e., already using the real-time cycled conditions) from 01 Dec 2010.
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model
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MEANT Level 2 (-0.25 m) T
CYCLE Level 2 (-0.25 m) Ice T
DifferenceLevel 2 T (-0.25 m)CYCLE – MEANT
Averages at Forecast hour 00
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MEANT Level 4 (-1.5 m) Ice T
CYCLE Level 4 (-1.5 m) Ice T
DifferenceLevel 4 T (-1.5 m)CYCLE – MEANT
Averages at Forecast hour 00
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MEANT 2-m air Temperature
CYCLE 2-m air Temperature
Difference2-m air TCYCLE – MEANT
Averages at Forecast hour 72
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Short-term plans for sea-ice code in WRF, particularly Noah LSM
• Currently, sea-ice code is scattered throughout the Noah LSM code– Difficult to trace the sea-ice processes through the code– Difficult to develop or replace
• Plan: Pull sea-ice code out of Noah-LSM, and make the Noah sea-ice treatment its own separate WRF module– Easy to trace the sea-ice processes through the code– Easy to develop or replace
• A place to link up with more sophisticated sea-ice schemes or models– Easy to use with other LSM options (e.g., the new Noah-MP
LSM)
Workshop on Polar Simulations with the Weather Research and Forecasting (WRF) Model