les conditions météorologiques en arctique
TRANSCRIPT
Les conditions météorologiques en Arctique
Elena Maksimovich
photo NABOS expedition, August 2006
Arctic Weather is controlled by :
Large scale air mass movement &
interaction
Surface state : open sea or sea ice cover
sea ice concentrations
extent/shape !!!
Iceberg size up to 320m x 280m x 40m
Sea Ice 1-6 m thickness
with pressure ridges up to 20 m high
Iceberg : continental snow accumulation due to precipitation
Sea Ice : frozen sea water
photo NABOS expedition, August 2006
Arctic Icebergs and Sea Ice
sea ice drift 24-27 April 2007 50 km within 3 days
Fanny Girard-Ardhuin
5-20 km/day 10-80 km/week
transpolar sea ice drift
common iceberg tracks
iceberg calving areas
drift speed
2007
Kwok et al., 2009
Vihma et al., 2008, GRL
April May June July Aug Sept
April May June July Aug Sept
2m
air
te
mp
era
ture
°C
10
m w
ind
sp
eed
m/s
ec
Meteorological observations in the Arctic Ocean
Tara drift in 2007 (March-Sept)
SHEBA drift in 1998 (March-Sept)
Russian ice drifting stations in 1936-1991
September Sea Ice extent in 1979-1983
September Sea Ice extent in 2007
daily mean values
water temperature +2 / -2°C
cold air sliding underneath -30/-40°C
HIGH pressure
warm air rising
Air masses
cold air outbreak
Large thermal differences create favorable conditions for cyclone development &
regeneration !!!
convection within the
lowest 1-2 km
convective clouds are aligned in the wind direction
sea ice
open sea
-10/+2°C LOW pressure
sea ice
summer
winter
Siberia
Alaska
Norway
Norway
Siberia
Alaska
Strom Tracks
North Pole
North Pole
maps : Canadian Coast Guard www.ccg-gcc.gc.ca
TYPICAL = ONLY POSSIBLE
Cyclones are much stronger & progress
faster in winter
In summer cyclones often shape also
within the coastal areas
Polar Lows
build-up within a few hours
100-500 km diameter
1-2 day lifetime
winds up to 35 m/s (70 kts)
mostly in winter
Polar Low regions
Turner, 2003 Noer, 2009
up to 15 Polar Lows per month in the
Barents Sea
development of convective clouds
sudden & unexpected drop in sea level pressure
rapid increase in wind (15 kts to 45 kts in less than 15 minutes)
heavy snow flurries at a ship or land station
“black eye” in the center of
the white cloud field = danger!
Polar Low indicators
Satellite image and ptoto at Andøya, Norway, 4 March 2008 Dörnbrack et al., 2011
frost/icing le givre
photo NABOS expedition, August 2006
Arctic FOG and HAZE
FOG : primarily a summer-time phenomenon (June-August)
warm moist air (+10°C) from Siberia, Alaska, Canada moves over colder sea ice and open sea (-10-0°C); or cold air (-20°C) advection over warmer open sea (-10-0°C) ice crystals of the fog perturb the radar signature visibility < 1.5 km
HAZE : mostly in spring on clear sky days
high concentration of dust particles “locked” in the boundary layer vertically 100m - up to 1 km height stretching within 10-200 km distances visibility < 3-5 km
photo Ann-Christineengvall
Ny-Alesund, Svalbard spring 2006
HAZE
Satellite data : water vapor, ice & liquid water content,
wind speed, sea ice concentrations/drift
INFO on current weather & sea ice conditions
Ground-based observations coastal stations, drifting buoys, ship reports
Numerical weather analysis/forecast for ex, TOPAZ ice model for Barents Sea
22:30 GMT 4 Feb 2012 NOAA GOES
SeaWinds on QuikSCAT
Real-Time satellite retrievals of the wind speed & direction
Polar Orbiting Satellites
14 times daily
wind speed
is traced by cloud
displacement
www.stratus.ssec.wisc.edu/products/rtpolarwinds/ (MODIS and AVHRR sensors)
12:30 GMT 1 Feb 2012
13:07 GMT 1 Feb 2012
14:49 GMT 1 Feb 2012
from NE 60 nots
from NE 20 nots
winds above 400 mb (7 km) winds within 400-700 mb
winds below 700 mb (3 km)
Real-Time and FREE Numerical Weather Data and Forecast
for individual Arctic sectors
Norwegian Meteorological Institute http://met.no
Met Office, UK
www.metoffice.gov.uk
NOAA National Weather Service www.nws.noaa.gov
Environment Canada
www.weatheroffice.gc.ca
Russian Hydro-Meteorological Inst.
http://esimo.ru (only in russian)
Intern. Arctic Buoy Programme http://iabp.apl.washington.edu
Technology for Iceberg Detection and Tracking
courtesy K.J. Eik, 2009; G. Broström et al., 2009
Iceberg drift in 1988
(buoy data)
Sea Ice and Iceberg Drift Forecast
requires real-time and high resolution :
weather forecast
pressure, wind, air temperature
oceanographic data
currents, water temperatures, tides, waves
ice observations
thickness, concentrations, roughness
photo Sveinung Løset
International Ice Patrol (US) www.uscg.mil/lantarea/iip/home.html
Norwegian Meteorological Institute TOPAZ model in 2-4 km resolution
http://met.no
Real-Time Iceberg detection and tracking
Courtesy I. Keghouche, 2010
sources of icebergs Shtokman Gaz Condensate Field
ocean currents
Courtesy F. Counillon, 2011
Random Iceberg drift experiment
Zolo
tou
khin, 2
00
9 Canadian East Coast, 1986
OIL !!
Shtokman
oil tanker Overseas Ohio, 2003 iceberg damage
Intelligent managing needed !!!
Thank you for your attention
20 photo: François Bernard