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THORPEX-Pacific Workshop Kauai, Hawaii
Polar Meteorology Group, Byrd Polar Research Center, The Ohio State University, Columbus, Ohio
David H. Bromwich1,2 and Keith M. Hines1
1Polar Meteorology GroupByrd Polar Research CenterThe Ohio State University
Columbus, Ohio, USA
2Atmospheric Sciences ProgramDepartment of GeographyThe Ohio State University
Columbus, Ohio, USA
Arctic IPY (2007-2009):Arctic System
Reanalysis
Arctic IPY (2007-2009):Arctic System
Reanalysis
THORPEX-Pacific Workshop Kauai, Hawaii
Polar Meteorology Group, Byrd Polar Research Center, The Ohio State University, Columbus, Ohio
Links Between the Pacific and ArcticLinks Between the Pacific and Arctic Aleutian Low – especially important for
winter PNA Pattern – ENSO/Wave propagation Pacific Decadal Oscillation September 2007 All-Time Minimum in
Arctic Sea Ice Extent – concentrated in the Pacific Sector
IPY (2007/9) Overlaps with Wintertime THORPEX-Pacific (Jan.-Mar. 2009)
The storm of 19 October 2004 as depicted by the NCEP/NCAR global reanalysis. Contours represent isobars of sea level pressure at increments of 3 hPa. [from visualization package of NOAA Climate Diagnostics Center]
The Figure shows an intense storm depicted in the NCEP/NCAR reanalysis for 19 October 2004. The storm led to flooding of Nome, Alaska, and has a central pressure of 949 hPa in the reanalysis. The actual central pressure deduced by the National Weather Service was as low as 941 hPa.
The Need for Improved Atmospheric Reanalyses
Arctic System Reanalysis Arctic System Reanalysis (ASR)(ASR)an NSF-Funded IPY Projectan NSF-Funded IPY Project1. Rapid climate change is occurring in the Arctic. An integrated
picture of coupled atmosphere/land surface/ ocean interactions is needed on synoptic and climatic time scales.
2. Global reanalyses encounter many problems at high latitudes. The ASR would use the best available description for Arctic processes and would enhance the existing database of Arctic observations. The ASR will be produced at improved temporal resolution and much higher spatial resolution.
3. The ASR would provide fields for which direct observation are sparse or problematic (precipitation, radiation, cloud, ...) at higher resolution than from existing reanalyses.
4. The system-oriented approach provides community focus including the atmosphere, land surface and sea ice communities.
5. The ASR will provide a convenient synthesis of Arctic field programs and integrate Pacific region observations.
ASR OutlineA physically-consistent integration of Arctic and
other Northern Hemisphere data
Current Participants:Ohio State University - Byrd Polar Research Center (BPRC)
- and Ohio Supercomputer Center (OSC)National Center Atmospheric Research (NCAR)Universities of Colorado, Illinois, and Alaska-Fairbanks
High resolution in space (<20 km) and time (3 hours)- convenient for synoptic studies
Begin with years 2000-2010 (Earth Observing System)
Also Interested:NOAA (Also provided start-up funds) NASAU.S. Department of Energy
Pressure at SHEBA Camp and Barrow January 1998
1000
1005
1010
1015
1020
1025
1030
1035
1040
1045
1050
1 6 11 16 21 26 31January 1998
Pre
ssu
re (
hP
a)
2 9 .5 3 0 1
PWRF 2.3 SHEBAPWRF 2.3 Barrow, AlaskaSHEBA ObservationsBarrow, Alaska Observations
ASR Numerical Model: Polar WRFWeather Research and Forecasting Model
SHEBA 1997/8 Grid
January 1998 Results
Polar Optimization at theByrd Polar Research Center:Fractional sea iceSea ice albedoMorrison microphysics (2-moment)Noah LSM modificationsHeat transfer through snow and ice
ASR High Resolution Domain
Outer Grid: ~45 km resolution
Inner Grid: ~15 km resolution
Vertical Grid: ~70 levels
ASR will detail the downstreamimpacts from the Pacific sector
Numerical Experiments within the ASR Framework
• The ASR will employ modern, efficient Data Assimilation techniques.
• Observing System Experiments (OSEs) are numerical model-based experiments to test the impact of new and existing observations. Sometimes called “data denial” experiments.
• Observing System Simulation Experiments (OSSEs) are numerical experiments that test impacts of future observing systems, e.g., new satellite sensors and Automatic Weather Stations
• Determine the observations needed to optimize the Arctic observing system.
Other Considerations for the Other Considerations for the ASRASR
• Impact of Pacific weather on Alaska and Impact of Pacific weather on Alaska and the Beaufort Sea, including extreme the Beaufort Sea, including extreme eventsevents
• New and improved Data Assimilation in New and improved Data Assimilation in cloudy areascloudy areas
• Optimized numerical modeling for the Optimized numerical modeling for the Arctic (e.g., mixed-phase clouds, variable Arctic (e.g., mixed-phase clouds, variable sea ice characteristics, and realistic sea ice characteristics, and realistic Arctic land representation – e.g., Arctic land representation – e.g., permafrost)permafrost)
• Interaction of Ocean and Sea Ice Interaction of Ocean and Sea Ice communities with the Atmospheric communities with the Atmospheric ReanalysisReanalysis
THORPEX-Pacific Workshop Kauai, Hawaii
Polar Meteorology Group, Byrd Polar Research Center, The Ohio State University, Columbus, Ohio
Key Points for ASR and THORPEX-Pacific
Key Points for ASR and THORPEX-Pacific
Synoptic and Climate Applications Detailing Arctic features downstream of the
Pacific Sector Combining remote sensing, modeling and
in-situ observations High resolution Polar WRF simulations Advanced Data Assimilation Expansion to the 1957-2000 period? ASR Planning Meeting late February at
NCAR … consider THORPEX-Pacific contribution?