N.N.

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Atmospheric modeling in ProClim by Anne
D. Sandvik
TITLE OF PRESENTATION by N.N.
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ProClim, WP 2 Water mass formation on shelves

• Atmospheric modeling

Perform nonhydrostatic 1-2 km resolution model
studies of Storfjorden and the westernBarents
Sea, and make the atmospheric model available for
coupling to the ice-ocean model
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Motivation

• HINDCAST wind (75 km) and observations from Hopen
• High-resolution model estimated wind
• Impact on the circulation and Polynia dynamics
  due to resolution in the wind forcing?

• Coupled ice-ocean-atmospheric model

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Preliminary workplan

• 4 km atmospheric forcing 1998-1999 (Ragnheid, MM5
  -gt BOM)
• Validation against synoptic observations, 2003
• Case study polar low, March 11, 2003
• Sensitivity to ice cover (in Storfjorden)
• MM5 - ROMS

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MM5, NCAR/Penn State mesoscale model

• Non hydrostatic
• Polar mode
• 23 vertical sigma level (40m 15 km)
• One way nesting 12 -gt 4km
• Initial and lateral boundary values (ECMWF)

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Model domain 12 -gt 4 km ( BOM)
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• Wind observations, Hopen 1998 1/9 2002

• Hopen is not represented in the MM5 4 km domain

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MM5 estimated temperature and wind

• 1/8 1/12, 1998
• 1/1 1/5, 1999

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Wind speed, Hopen
Wind speed at Hopen, observation 10 m asl (red
line) and model estimated wind about 38 m agl
(blue line). The mean value and standard
deviation of the observations are indicated with
the green and black dashed lines respectively.
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How representative is Hopen for the Storfjorden
area?
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Hopen Storfjorden, Sep., 1998
Correlation coefficient for temperature (left)
and wind speed (right) estimated between the MM5
Hopen gridpoint and all other gridpoints in the 4
km domain.
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Hopen Storfjorden, Sep., 1998
Correlation coefficient for wind direction
estimated between the MM5 Hopen gridpoint and all
other gridpoints in the 4 km domain.
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Summary subtask 1

• Hopen obs Hopen MM5

• Hopen MM5 Storfjorden MM5

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Validation of MM5 against available data in
Arctic, March 2003

• Temperature, wind speed and direction
• Hopen
• Longyearbyen
• Ny-Ålesund

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Model domain 12 -gt 4 km
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Ice cover from ECMWF
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Wind, 9/3 03, 1200 UTC
ECMWF interpolated to 4 km MM5 domain
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Temperature, March 2003
Temperature at Hopen, observation 2 m asl (blue
line) and model estimated temperature about 38 m
agl (red line). The mean value and standard
deviation of the observations are indicated with
the green and black dashed lines respectively.
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Wind speed, March 2003
Wind speed at Hopen, observation 10 m asl
(blue line) and model estimated wind about 38 m
agl (red line). The mean value and standard
deviation of the observations are indicated with
the green and black dashed lines respectively
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Temperature and wind speed, March 2003
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Wind speed and direction, March 2003
Wind roses for March 2003, observations in the
left panel and MM5 Hopen in right panel. The
direction is divided into 24, 15 deg bins. The
numbers on the inner and outher circle show the
at the given direction. Blue shows wind speeds
from 0 5 m/s, pink from 5 10 m/s and yellow
from 10 15 m/s.
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Polar low, March 11, 2003
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(No Transcript)
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Polar low, March 11, 2003
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Work in progress

• Case study polar low, March 11, 2003
• Sensitivity to ice cover
• Atmospheric boundary layer over ice
• Method for picking interesting cases from
  ERA-40

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Work in progress

• MM5 -gt BOM
• MM5 -gt ROMS(ICE) -gt MM5 -gt ROMS(ICE)

Input?