geostrophic balance
140
large number of US Institutions and a few in Europe. Results were published
in a set of atlases.
geostrophic balance if the Coriolis force on a moving fluid is fully compensated by
the pressure force, the fluid is in geostrophic balance. In that case the current is parallel to the isobars, clockwise around high pressure centers in the
northern hemisphere and anticlockwise in the southern hemisphere. BuysBallot's (1817-1890) law in meteorology is the consequence of geostrophic
balance. In the open ocean the assumption of geostrophic balance is often
applied to the pressure field derived from the temperature and salinity
observations to calculate the current relative to the level of no-motion. Exact
geostrophic motion would result in stationary flow. In reality apparently
geostrophic flow changes gradually, so there is a small deviation from the
balance. These conditions are called quasi-geostrophic motion.
geothermal heat flow heat flow from the inner earth. It can usually be neglected
in heat calculations, compared with the other fluxes, but it is used in geophysical and geological research as a way to obtain information of the subbottom structure. Its average over the whole earth is 1.2 10- 6 cal cm-2 S-I.
German Deep-Sea Expedition ~Valdivia Expedition.
Gilbert epoch, -chron ~magnetostratigraphy.
gill nets ~nets.
glacial epoch (syn. ice age) any part of geologic time in which the climate was
significantly colder than today. Glacial epochs are characterized by widespread glaciers (~ice shelf and ~ice sheet) which moved from the poles
towards the equator and covered a much larger area than today. The maximum of the most recent glacial epoch was 18000 years ago.
glaciation the formation and advancement of glaciers and ice sheets towards lower
altitudes, and action on the earth's surface by glacial activity.
glacier large mass of ice formed, at least in part, on land by compaction and
recrystallization of snow and surviving from year to year. Glaciers are able
to flow by creep under the influence of gravity. The term includes not only
the small mountain glaciers but also ice sheets, ice caps, and ice shelves.
glaciomarine sediments sediments transported in or on glaciers or floating ice
and deposited at the sea floor. Sediments transported in this way are often
very poorly sorted in grain size. Because of their particular character they are
easily distinguished from other marine sediments.
140
large number of US Institutions and a few in Europe. Results were published
in a set of atlases.
geostrophic balance if the Coriolis force on a moving fluid is fully compensated by
the pressure force, the fluid is in geostrophic balance. In that case the current is parallel to the isobars, clockwise around high pressure centers in the
northern hemisphere and anticlockwise in the southern hemisphere. BuysBallot's (1817-1890) law in meteorology is the consequence of geostrophic
balance. In the open ocean the assumption of geostrophic balance is often
applied to the pressure field derived from the temperature and salinity
observations to calculate the current relative to the level of no-motion. Exact
geostrophic motion would result in stationary flow. In reality apparently
geostrophic flow changes gradually, so there is a small deviation from the
balance. These conditions are called quasi-geostrophic motion.
geothermal heat flow heat flow from the inner earth. It can usually be neglected
in heat calculations, compared with the other fluxes, but it is used in geophysical and geological research as a way to obtain information of the subbottom structure. Its average over the whole earth is 1.2 10- 6 cal cm-2 S-I.
German Deep-Sea Expedition ~Valdivia Expedition.
Gilbert epoch, -chron ~magnetostratigraphy.
gill nets ~nets.
glacial epoch (syn. ice age) any part of geologic time in which the climate was
significantly colder than today. Glacial epochs are characterized by widespread glaciers (~ice shelf and ~ice sheet) which moved from the poles
towards the equator and covered a much larger area than today. The maximum of the most recent glacial epoch was 18000 years ago.
glaciation the formation and advancement of glaciers and ice sheets towards lower
altitudes, and action on the earth's surface by glacial activity.
glacier large mass of ice formed, at least in part, on land by compaction and
recrystallization of snow and surviving from year to year. Glaciers are able
to flow by creep under the influence of gravity. The term includes not only
the small mountain glaciers but also ice sheets, ice caps, and ice shelves.
glaciomarine sediments sediments transported in or on glaciers or floating ice
and deposited at the sea floor. Sediments transported in this way are often
very poorly sorted in grain size. Because of their particular character they are
easily distinguished from other marine sediments.