Dataset: seaice
Deployment: LMG0106

Sea Ice data from Southern Ocean cruises
Principal Investigator: 
Chris H. Fritsen (Desert Research Institute, DRI)
BCO-DMO Data Manager: 
Ms Dicky Allison (Woods Hole Oceanographic Institution, WHOI BCO-DMO)
Project: 
Coordinated Deployments:
Description

Sea Ice Observations during Southern Ocean GLOBEC

Sea ice observations on the Southern Ocean GLOBEC cruises were conducted according to standardized protocols developed and utilized by members of the Antarctic Sea Ice Processes and Climate working group (co-sponsored by SCAR and GlOCHANT).

Related datasets:
ice properties, ice thickness, snow pits

More details regarding methodology can be found at http://www.scar.org/GLOCHANT/ASPeCt/seaiceobs.htm or by contacting Dr. C.H. Fritsen at cfritsen@dri.edu.

OPEN WATER (OpnWtrCode):
Code --- Description
0 --- No openings
1 --- Small cracks
2 --- Very narrow breaks, <50m

3 --- Narrow breaks, 50-200 m
4 --- Wide breaks, 200-500 m
5 --- Very wide breaks, >500 m
6 --- Lead/coastal lead
7 --- Polynya/coastal polynya
8 --- Water broken only by small scattered floes
9 --- Open sea

ICE CONCn (IceCon): to be expressed in tenths.

ICE TYPE (ITypeCode):
Code --- Description
10 --- Frazil
11 --- Shuga
12 --- Grease
20 -- Nilas
30 --- Pancakes
40 --- Young grey ice, 0.1-0.15 m
50 --- Young grey-white ice, 0.15-0.3 m
60 --- First year, 0.3-0.7 m
70 --- First year, 0.7-1.2 m
80 --- First year, >1.2 m
85 --- Multiyear floes
90 --- Brash
95 --- Fast ice

SEA ICE (IThkns) AND SNOWTHICKNESS (SnoThkns): to be expressed in centimetres.

FLOE SIZE (FloSzCode):
Code --- Description
100 --- Pancakes
200 --- New sheet ice
300 --- Brash/broken ice
400 --- Cake ice, <20 m

500 --- Small floes, 20-100 m
600 --- Medium floes, 100-500 m
700 --- Large floes, 500-2000 m
800 --- Vast floes, >2000 m

SNOW TYPE (SnoTypCode):
Code --- Description
0 --- No snow observation
1 --- No snow, no ice or brash
2 --- Cold new snow, < 1 day old
3 --- Cold old snow
4 --- Cold wind-packed snow
5 --- New melting snow (wet new snow)
6 --- Old melting snow
7 --- Glaze
8 --- Melt slush
9 --- Melt puddles
10 --- Saturated snow (waves)
11 --- Sastrugi

TOPOGRAPHY (TopoCode):
Code Description
100 Level ice
200 Rafted pancakes
300 Cemented pancakes
400 Finger rafting
5xy New, unconsolidated ridges (no snow)
6xy New ridges filled with snow or a snow cover
7xy Consolidated ridges (no weathering)
8xy Older, weathered ridges
x values Areal Coverage
0 0-10%
1 10-20%
2 20-30%
3 30-40%
4 40-50%
5 50-60%
6 60-70%
7 70-80%
8 80-90%
9 90-100%
y values Avg. Sail Height
1 0.5 m
2 1.0 m
3 1.5 m
4 2.0 m
5 3.0 m
6 4.0 m
7 5.0 m

The following weather observation codes and descriptions are from the "National Weather Service Observing Handbook No. 1", Marine Surface Weather Observations, August 1995. U.S. Department of Commerce, Silver Spring, MD.

VISIBILITY (visib):
Code --- Visibility in m/km
90 --- less than 50 m
91 --- 50 but less than 200 m
92 --- 200 but less than 500 m
93 --- 500 but less than 1000 m
94 --- > 1 but less than 2 km
95 --- > 2 but less than 4 km
96 --- > 4 but less than 10 km
97 --- > 10 but less than 20 km
98 --- > 20 but less than 50 km
99 --- > 50 km or more

TOTAL CLOUD COVER (cldcvr): to be expressed in eighths; -1 = Sky obscured by fog, snow or other met. phenom.

PRESENT WEATHER (wx):
Code Description
  Change of sky during past hour
0 Cloud development not observable
1 Clouds dissolving or becoming less developed
2 State of the sky on the whole unchanged
3 Clouds generally forming or developing
  Phenomena in past hour but not at time of obs
28 Fog (in past hour, but not at time of obs.)
   
36 Slight or moderate drifting snow, low (below eye level)
37 Heavy drifting snow, low (below eye level)
38 Slight or moderate drifting snow, high (above eye level)
39 Heavy drifting snow, high (above eye level)
  Fog at the time of observation
41 Sky visible
Fog in patches (visibility may be greater than 1/2 nm)
42 Sky visible
Fog has become thinner in past hour
43 Sky invisible
For has become thinner in past hour
44 Sky visible
Fog, no change in past hour
45 Sky invisible
Fog, no change in past hour
46 Sky visible
Fog has begun or thickened in past hour
47 Sky invisible
Fog has begun or thickened in past hour
  Drizzle
50 Intermittent
Slight drizzle
56 Slight
Freezing drizzle
  Rain (Not falling as showers)
60 Intermittent
Slight rain
  Solid precipitation not falling as showers
70 Intermittent
Slight snow in flakes
71 Continuous
Slight snow in flakes
72 Intermittent
Moderate snow in flakes
73 Continuous
Moderate snow in flakes
74 Intermittent
Heavy snow in flakes
75 Continuous
Heavy snow in flakes
76 Diamond dust (with or without fog)
77 Snow grains (with or without fog)
  Solid precipitation in showers
85 Slight
Shower of snow
86 Moderate or heavy
Shower of snow
More information about this dataset deployment