The greatest ice draft reduction occurred in the central and eastern Arctic.
Ice draft is a measurement of the ice thickness below the waterline and often serves as a close proxy for total ice thickness.
Together, the Beaufort Gyre and Transpolar Drift strongly influence the Arctic Ocean ice thickness distribution, which has been determined largely from submarine sonar measurements of the ice draft.
Studies of sea ice thickness to date have involved analysis of ice draft data acquired by single-beam ice profiling sonars on US and British Navy submarines or single-beam moored sonars.
This is represented in the model by a non-dimensional parameter of change in ice shelf area as function of depth (dw/dz), which was computed by binning and normalizing the gridded ice draft data40 into 200 m depth bins.
Submarine sonar data obtained since 1958 have revealed that the average ice draft in the Arctic Ocean in the 1990s decreased by over 1 m (about 3 feet) and that ice volume was 40percentt lower than during the period 1958 76.
The relatively smooth ice surface elevation of the freely floating central part of the glacier south of the MGO-ridge suggests that the ice shelf is in hydrostatic equilibrium, such that the depth of the ice draft below sea level is a direct measure of the local ice thickness.
However, too little is known about how thick the ice is, although surveys of sea-ice thickness undertaken by submarines suggest ice draft – the amount of water the floating Arctic ice displaces – may have reduced by about 40 per cent since the 1960s and 1970s.
Glasses of white wine and cups of ice-cold draft beer, two thirst-quenching staples of summer festivals, could soon become memories of days gone by on the streets of New York, as the Giuliani administration is considering banning the sale of alcohol at outdoor street parties.
There are heavenly fried clams and"Kids, sit down!"onion rings and coleslaw and, for you and your lovely, sunburned wife, plastic cups of ice-cold draft Bud.
After an ice-cold draft Singha or two, you'll probably agree.
