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).
\nRoutine observations of sea ice and snow characteristics were routinely collected on an hourly basis while the L.M. Gould was actively steaming throughout the cruise. These observations began on 26 July 2001 and continued through 27 August 2001. The observational protocol followed during the cruise was the protocol that is formally endorsed by the SCAR ASPeCt (Antarctic Sea ice Processes and Climate) program for observing sea ice characteristics. In short, our program (combined efforts of BG-244 as well as OG-241) was able to gather the information that will be used to characterize the predominate types of ice in the region according to parameters, such as areal coverage, floe size, ice thickness, snow type, snow thickness and deformation.
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).
\nRelated datasets:
\nice 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.
\nOPEN WATER (OpnWtrCode):
\nCode --- Description
\n0 --- No openings
\n1 --- Small cracks
\n2 --- Very narrow breaks, <50m
3 --- Narrow breaks, 50-200 m
\n4 --- Wide breaks, 200-500 m
\n5 --- Very wide breaks, >500 m
\n6 --- Lead/coastal lead
\n7 --- Polynya/coastal polynya
\n8 --- Water broken only by small scattered floes
\n9 --- Open sea
ICE CONCn (IceCon): to be expressed in tenths.
\nICE TYPE (ITypeCode):
\nCode --- Description
\n10 --- Frazil
\n11 --- Shuga
\n12 --- Grease
\n20 -- Nilas
\n30 --- Pancakes
\n40 --- Young grey ice, 0.1-0.15 m
\n50 --- Young grey-white ice, 0.15-0.3 m
\n60 --- First year, 0.3-0.7 m
\n70 --- First year, 0.7-1.2 m
\n80 --- First year, >1.2 m
\n85 --- Multiyear floes
\n90 --- Brash
\n95 --- Fast ice
SEA ICE (IThkns) AND SNOWTHICKNESS (SnoThkns): to be expressed in centimetres.
\nFLOE SIZE (FloSzCode):
\nCode --- Description
\n100 --- Pancakes
\n200 --- New sheet ice
\n300 --- Brash/broken ice
\n400 --- Cake ice, <20 m
500 --- Small floes, 20-100 m
\n600 --- Medium floes, 100-500 m
\n700 --- Large floes, 500-2000 m
\n800 --- Vast floes, >2000 m
SNOW TYPE (SnoTypCode):
\nCode --- Description
\n0 --- No snow observation
\n1 --- No snow, no ice or brash
\n2 --- Cold new snow, < 1 day old
\n3 --- Cold old snow
\n4 --- Cold wind-packed snow
\n5 --- New melting snow (wet new snow)
\n6 --- Old melting snow
\n7 --- Glaze
\n8 --- Melt slush
\n9 --- Melt puddles
\n10 --- Saturated snow (waves)
\n11 --- Sastrugi
| Code | \nDescription | \n
|---|---|
| 100 | \nLevel ice | \n
| 200 | \nRafted pancakes | \n
| 300 | \nCemented pancakes | \n
| 400 | \nFinger rafting | \n
| 5xy | \nNew, unconsolidated ridges (no snow) | \n
| 6xy | \nNew ridges filled with snow or a snow cover | \n
| 7xy | \nConsolidated ridges (no weathering) | \n
| 8xy | \nOlder, weathered ridges | \n
| x values | \nAreal Coverage | \n
| 0 | \n0-10% | \n
| 1 | \n10-20% | \n
| 2 | \n20-30% | \n
| 3 | \n30-40% | \n
| 4 | \n40-50% | \n
| 5 | \n50-60% | \n
| 6 | \n60-70% | \n
| 7 | \n70-80% | \n
| 8 | \n80-90% | \n
| 9 | \n90-100% | \n
| y values | \nAvg. Sail Height | \n
| 1 | \n0.5 m | \n
| 2 | \n1.0 m | \n
| 3 | \n1.5 m | \n
| 4 | \n2.0 m | \n
| 5 | \n3.0 m | \n
| 6 | \n4.0 m | \n
| 7 | \n5.0 m | \n
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.
\nVISIBILITY (visib):
\nCode --- Visibility in m/km
\n90 --- less than 50 m
\n91 --- 50 but less than 200 m
\n92 --- 200 but less than 500 m
\n93 --- 500 but less than 1000 m
\n94 --- > 1 but less than 2 km
\n95 --- > 2 but less than 4 km
\n96 --- > 4 but less than 10 km
\n97 --- > 10 but less than 20 km
\n98 --- > 20 but less than 50 km
\n99 --- > 50 km or more
TOTAL CLOUD COVER (cldcvr): to be expressed in eighths; -1 = Sky obscured by fog, snow or other met. phenom.
\n| Code | \nDescription | \n
|---|---|
| \u00a0 | \nChange of sky during past hour | \n
| 0 | \nCloud development not observable | \n
| 1 | \nClouds dissolving or becoming less developed | \n
| 2 | \nState of the sky on the whole unchanged | \n
| 3 | \nClouds generally forming or developing | \n
| \u00a0 | \nPhenomena in past hour but not at time of obs | \n
| 28 | \nFog (in past hour, but not at time of obs.) | \n
| \u00a0 | \n\u00a0 | \n
| 36 | \nSlight or moderate drifting snow, low (below eye level) | \n
| 37 | \nHeavy drifting snow, low (below eye level) | \n
| 38 | \nSlight or moderate drifting snow, high (above eye level) | \n
| 39 | \nHeavy drifting snow, high (above eye level) | \n
| \u00a0 | \nFog at the time of observation | \n
| 41 | \nSky visible \n\t\t\tFog in patches (visibility may be greater than 1/2 nm) | \n
| 42 | \nSky visible \n\t\t\tFog has become thinner in past hour | \n
| 43 | \nSky invisible \n\t\t\tFor has become thinner in past hour | \n
| 44 | \nSky visible \n\t\t\tFog, no change in past hour | \n
| 45 | \nSky invisible \n\t\t\tFog, no change in past hour | \n
| 46 | \nSky visible \n\t\t\tFog has begun or thickened in past hour | \n
| 47 | \nSky invisible \n\t\t\tFog has begun or thickened in past hour | \n
| \u00a0 | \nDrizzle | \n
| 50 | \nIntermittent \n\t\t\tSlight drizzle | \n
| 56 | \nSlight \n\t\t\tFreezing drizzle | \n
| \u00a0 | \nRain (Not falling as showers) | \n
| 60 | \nIntermittent \n\t\t\tSlight rain | \n
| \u00a0 | \nSolid precipitation not falling as showers | \n
| 70 | \nIntermittent \n\t\t\tSlight snow in flakes | \n
| 71 | \nContinuous \n\t\t\tSlight snow in flakes | \n
| 72 | \nIntermittent \n\t\t\tModerate snow in flakes | \n
| 73 | \nContinuous \n\t\t\tModerate snow in flakes | \n
| 74 | \nIntermittent \n\t\t\tHeavy snow in flakes | \n
| 75 | \nContinuous \n\t\t\tHeavy snow in flakes | \n
| 76 | \nDiamond dust (with or without fog) | \n
| 77 | \nSnow grains (with or without fog) | \n
| \u00a0 | \nSolid precipitation in showers | \n
| 85 | \nSlight \n\t\t\tShower of snow | \n
| 86 | \nModerate or heavy \n\t\t\tShower of snow | \n
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.