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Seasonal variations in currents and water properties in northwestern Baffin Bay, 1978–1979
750
A. Physical Oceanography
OLR (1982) 29 (12)
Nine satellite-tracked, drifting surface buoys were deployed in the Kuroshio region. Position accuracy was very high, and effects of wind on the speed and course of the buoys were negligible. While composite trajectories showed classical ocean circulation, heretofore unknown mesoscale features (e.g., a cold eddy east of Okinawa) were discovered. Qualitatively, the experiment proved the long-term usefulness of drifting buoys for surface current measurement, particularly in areas where conventional ship observation is ineffective. Maritime Safety Agency, Tokyo, Japan. (jch)
Nearshore tidal currents can be considerably stronger due to internal tides. Evidence of inertial oscillations was present in the records from uppermost moored current meters; typical amplitudes were 10 to 20 cm/s, with speeds as high as 35 cm/s. Magnitude decreases rapidly with depth; at 250 m, inertial oscillations are difficult to resolve from semi-diurnal tidal currents. They resulted, in large part, from changes in local surface wind; at times of solid ice cover, amplitudes were markedly reduced. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada.
82:5904 Whitfield, Michael, 1982. Seawater under extreme pressure. Nature, Lond., 297(5867):p.538.
82:5908 Fissel, D.B., D.D. Lemon and J.R. Birch, 1982. Major features of the summer near-surface circulation of western Baffin Bay, 1978 and 1979. Arctic. 35(1): 180-200.
information about the properties of seawater and the reactions of its constituents in-situ is rapidly becoming available. A new equation of state for seawater has been established, and data on ionic molal volumes and compressibilities over oceanic temperature and pressure ranges have been compiled. Mar. Biol. U.K., Plymouth, PL1 2PB, UK. (dlf)
A40. Area studies, surveys 82:5905 De Maio, Arturo, Mauro Moretti, Emilio Sansone, Giancarlo Spezie and Mario Vultaggio, 1978/79. Dynamics of the waters in the Gulf of Naples: maps of temperature and salinity at standard depths. Annali Ist. nay. Napoli, 47/48:215-231. (In Italian, English abstract.) Ist. Univ. Navale, Napoli, Italy. 82:5906 Dhanalakshmi, S., 1982. Wave refraction and nearshore circulation at Visaldmpatnam [east India]. Indian J. mar. Sci., 11(2):153-158. Waves, nearshore circulation and currents in a region influenced by the outer harbour were investigated. All regions of wave convergence prior to construction of the outer harbour have become regions of either mild divergence or mild convergence. The shoreline is generally in better equilibrium than before. Dept. of Geogr., Andhra Univ., Waltair 530 003, India. 82:5907 Fissel, D.B., 1982. Tidal currents and inertial oscillations in northwestern Baffin Bay. Arctic, 35(1): 201-210. Offshore, the largest diurnal and semi-diurnal tidal currents were in all cases < 8 cm/s in amplitude.
The near-surface circulation is dominated by the southward-flowing Baffin Current which is largely confined to within 100 km of the coast. It varies in both intensity and width, with strongest flows occurring where the current follows a cyclonic intrusion into and out of eastern Lancaster Sound; here in the core of the current the median nearsurface speeds are 75 cm/s, decreasing with depth. East of Devon, Bylot and Baffin islands, the current is well-defined, but generally less intense. Transient large-scale meanders and anticyclonic eddies of ~ 2 0 km diameter were observed. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada. 82:5909 John, V.C. and K.S. Pal, 1982. Tidal current fluctuations in Bombay Harbour. Indian J. mar. Sci., 11(2):159-166. Engrs. India Ltd., Post Box No. 730, New Delhi 110 001, India. 82:5910 Lakshmanan, P.T., C.S. Shynamma, A.N. Balchand, P.G. Kurup and P.N,K. Nambisan, 1982. Distribution and seasonal variation of temperature and salinity in Cochin Backwaters [west India]. Indian J. mar. Sci., 11(2):170-172. Nambisan: Dept. of Mar. Sci., Univ. of Cochin, Cochin 682016, India. 82:5911 Lemon, D.D. and D.B. Fissel, 1982. Seasonal variations in currents and water properties in northwestern Baffin Bay, 1978-1979. Arctic, 35(1):211-218. Significant seasonal changes in current speed and direction, temperature and conductivity closely followed seasonal sea-ice cover. General winter weakening of near-surface currents (by a factor of 2
OLR (I982)29 (12)
A. PhysicalOceanography
or more) was observed; deeper currents exhibited a smaller decrease, resulting in a general decrease in baroclinicity (except off the north coast of Bylot Island, where the deep currents reversed). A salinity increase with freezing winter temperatures was observed in the upper water column; at some sites this uniform layer appeared to deepen at a rate of 40-50 m per month to a maximum depth from 200-250 m. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada. 82:5912 Tanaka, Iori, 1982. Direct measurements of horizontal divergence in the surface layer of the subarctic open sea in summer. Bull. Fac. Fish. Hokkaido Univ., 33(1):24-34. (In Japanese, English abstract.)
Horizontal divergence measurements revealed 2 main components, one with periodicity 1.5-4 hr and another trending linearly over a wide range; magnitude of the former is well explained by internal waves. The measurement site exhibited a layered structure with a seasonal pycnocline. Lab. of Oceanogr. & Meteorol., Hokkaido Univ., Hokkaido, Japan.
A 5 0 . G e n e r a l h y d r o g r a p h y (distribution of c o m m o n oceanic properties) 82:5913 Clancy, R.M. (comment), T.M. Dillon and T.M. Powell (reply), 1982. A comment on observations of a surface mixed layer. Deep-Sea Res., 29(5A): 655-657. 82:5914 Evans, D.L., 1982. Observations of small-scale shear and density structure in the ocean. Deep-Sea Res., 29(5A):581-595.
Three North Atlantic locations near Bermuda, in the Gulf Stream, and midway between, were sampled. Mean square vertical shear correlated well with the square of the mean Brunt-V~tisal~t frequency over 100-m segments of the profiles; a change in slope of the vertical wavenumber spectrum of the vertical shear was observed at ~0.1 cpm. Richardson numbers computed over 2 m were of order 1. Tentative calculation of vertical eddy diffusivity yielded values of 0.1~).4 cm2/s for the non-Gulf Stream sites; Gulf Stream values were somewhat higher. Grad. Sch. of Oceanogr., Univ. of Rhode Island, Kingston, RI 02881, USA.
751
82:5915 Knysh, V.V., 1982. Multi-element four-dimensional analysis of the major hydrophysicul fields of the ocean. Fiz. Atmosf. Okeana, 18(4):391-398. (In Russian, English abstract.)
A90. Currents 82:5916 Hammond, R.R. and W.J. Wallace, 1982. Seabed drifter movement in San Diego Bay and adjacent waters. Estuar. coast. Shelf Sci., 14(6):623-634.
Results from 500 woodhead-type seabed drifters in San Diego Bay and adjacent waters distinguished 4 'significant bottom drift regimes': main bay channel, off-coast, open and semi-enclosed docking basins. A northward bottom current off-coast caused a net bottom-water inflow into the main channel. From the docking basins to offshore regions, the mean residual bottom drift ranged 04). 17 km/d. Effects of the cooling water intakes and heated effluents of local power plants on the overall circulation need quantitative investigation. Naval Ocean Systems Center, San Diego, Calif. 92152, USA. (isz) 82:5917 Heathershaw, A.D., 1982. Some observations of currents in shallow water during a storm surge. Estuar. coast. Shelf Sci., 14(6):635-648.
During a storm surge in Swansea Bay (Bristol Channel), residual flows may be five times higher than during quiescent flow periods. The observed flow regime suggests that while the residual circulation may be influenced by strong SW winds blowing onshore, offshore winds from the N W have a more significant effect, possibly as a result of wind-induced setdown in the bay head. Observed bottom currents can be predicted by a simple constant eddy viscosity model in which tidal mixing is dominant. Inst. of Oceanogr. Sci., Taunton, Somerset, UK. 82:5918 Mariette, V., G. Rougier, J.C. Salomon and B. Simon, 1982. Tidal currents in the Mer d'lrolse [NW France]. Oeeanologica Acta, 5(2): 149-159. (In French, English abstract.)
Tidal observations from British and French ports and from open sea points were used in a mathematical model that permitted calculation of currents for every nautical mile in the area and for every 3 minutes of time. Results were generally satisfactory although comparison between measured and calculated currents is difficult. Univ. de Bretagne
A. Physical Oceanography
OLR (1982) 29 (12)
Nine satellite-tracked, drifting surface buoys were deployed in the Kuroshio region. Position accuracy was very high, and effects of wind on the speed and course of the buoys were negligible. While composite trajectories showed classical ocean circulation, heretofore unknown mesoscale features (e.g., a cold eddy east of Okinawa) were discovered. Qualitatively, the experiment proved the long-term usefulness of drifting buoys for surface current measurement, particularly in areas where conventional ship observation is ineffective. Maritime Safety Agency, Tokyo, Japan. (jch)
Nearshore tidal currents can be considerably stronger due to internal tides. Evidence of inertial oscillations was present in the records from uppermost moored current meters; typical amplitudes were 10 to 20 cm/s, with speeds as high as 35 cm/s. Magnitude decreases rapidly with depth; at 250 m, inertial oscillations are difficult to resolve from semi-diurnal tidal currents. They resulted, in large part, from changes in local surface wind; at times of solid ice cover, amplitudes were markedly reduced. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada.
82:5904 Whitfield, Michael, 1982. Seawater under extreme pressure. Nature, Lond., 297(5867):p.538.
82:5908 Fissel, D.B., D.D. Lemon and J.R. Birch, 1982. Major features of the summer near-surface circulation of western Baffin Bay, 1978 and 1979. Arctic. 35(1): 180-200.
information about the properties of seawater and the reactions of its constituents in-situ is rapidly becoming available. A new equation of state for seawater has been established, and data on ionic molal volumes and compressibilities over oceanic temperature and pressure ranges have been compiled. Mar. Biol. U.K., Plymouth, PL1 2PB, UK. (dlf)
A40. Area studies, surveys 82:5905 De Maio, Arturo, Mauro Moretti, Emilio Sansone, Giancarlo Spezie and Mario Vultaggio, 1978/79. Dynamics of the waters in the Gulf of Naples: maps of temperature and salinity at standard depths. Annali Ist. nay. Napoli, 47/48:215-231. (In Italian, English abstract.) Ist. Univ. Navale, Napoli, Italy. 82:5906 Dhanalakshmi, S., 1982. Wave refraction and nearshore circulation at Visaldmpatnam [east India]. Indian J. mar. Sci., 11(2):153-158. Waves, nearshore circulation and currents in a region influenced by the outer harbour were investigated. All regions of wave convergence prior to construction of the outer harbour have become regions of either mild divergence or mild convergence. The shoreline is generally in better equilibrium than before. Dept. of Geogr., Andhra Univ., Waltair 530 003, India. 82:5907 Fissel, D.B., 1982. Tidal currents and inertial oscillations in northwestern Baffin Bay. Arctic, 35(1): 201-210. Offshore, the largest diurnal and semi-diurnal tidal currents were in all cases < 8 cm/s in amplitude.
The near-surface circulation is dominated by the southward-flowing Baffin Current which is largely confined to within 100 km of the coast. It varies in both intensity and width, with strongest flows occurring where the current follows a cyclonic intrusion into and out of eastern Lancaster Sound; here in the core of the current the median nearsurface speeds are 75 cm/s, decreasing with depth. East of Devon, Bylot and Baffin islands, the current is well-defined, but generally less intense. Transient large-scale meanders and anticyclonic eddies of ~ 2 0 km diameter were observed. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada. 82:5909 John, V.C. and K.S. Pal, 1982. Tidal current fluctuations in Bombay Harbour. Indian J. mar. Sci., 11(2):159-166. Engrs. India Ltd., Post Box No. 730, New Delhi 110 001, India. 82:5910 Lakshmanan, P.T., C.S. Shynamma, A.N. Balchand, P.G. Kurup and P.N,K. Nambisan, 1982. Distribution and seasonal variation of temperature and salinity in Cochin Backwaters [west India]. Indian J. mar. Sci., 11(2):170-172. Nambisan: Dept. of Mar. Sci., Univ. of Cochin, Cochin 682016, India. 82:5911 Lemon, D.D. and D.B. Fissel, 1982. Seasonal variations in currents and water properties in northwestern Baffin Bay, 1978-1979. Arctic, 35(1):211-218. Significant seasonal changes in current speed and direction, temperature and conductivity closely followed seasonal sea-ice cover. General winter weakening of near-surface currents (by a factor of 2
OLR (I982)29 (12)
A. PhysicalOceanography
or more) was observed; deeper currents exhibited a smaller decrease, resulting in a general decrease in baroclinicity (except off the north coast of Bylot Island, where the deep currents reversed). A salinity increase with freezing winter temperatures was observed in the upper water column; at some sites this uniform layer appeared to deepen at a rate of 40-50 m per month to a maximum depth from 200-250 m. Arctic Sci. Ltd., 1986 Mills Rd., R.R. 2, Sidney, BC V8L 3S1, Canada. 82:5912 Tanaka, Iori, 1982. Direct measurements of horizontal divergence in the surface layer of the subarctic open sea in summer. Bull. Fac. Fish. Hokkaido Univ., 33(1):24-34. (In Japanese, English abstract.)
Horizontal divergence measurements revealed 2 main components, one with periodicity 1.5-4 hr and another trending linearly over a wide range; magnitude of the former is well explained by internal waves. The measurement site exhibited a layered structure with a seasonal pycnocline. Lab. of Oceanogr. & Meteorol., Hokkaido Univ., Hokkaido, Japan.
A 5 0 . G e n e r a l h y d r o g r a p h y (distribution of c o m m o n oceanic properties) 82:5913 Clancy, R.M. (comment), T.M. Dillon and T.M. Powell (reply), 1982. A comment on observations of a surface mixed layer. Deep-Sea Res., 29(5A): 655-657. 82:5914 Evans, D.L., 1982. Observations of small-scale shear and density structure in the ocean. Deep-Sea Res., 29(5A):581-595.
Three North Atlantic locations near Bermuda, in the Gulf Stream, and midway between, were sampled. Mean square vertical shear correlated well with the square of the mean Brunt-V~tisal~t frequency over 100-m segments of the profiles; a change in slope of the vertical wavenumber spectrum of the vertical shear was observed at ~0.1 cpm. Richardson numbers computed over 2 m were of order 1. Tentative calculation of vertical eddy diffusivity yielded values of 0.1~).4 cm2/s for the non-Gulf Stream sites; Gulf Stream values were somewhat higher. Grad. Sch. of Oceanogr., Univ. of Rhode Island, Kingston, RI 02881, USA.
751
82:5915 Knysh, V.V., 1982. Multi-element four-dimensional analysis of the major hydrophysicul fields of the ocean. Fiz. Atmosf. Okeana, 18(4):391-398. (In Russian, English abstract.)
A90. Currents 82:5916 Hammond, R.R. and W.J. Wallace, 1982. Seabed drifter movement in San Diego Bay and adjacent waters. Estuar. coast. Shelf Sci., 14(6):623-634.
Results from 500 woodhead-type seabed drifters in San Diego Bay and adjacent waters distinguished 4 'significant bottom drift regimes': main bay channel, off-coast, open and semi-enclosed docking basins. A northward bottom current off-coast caused a net bottom-water inflow into the main channel. From the docking basins to offshore regions, the mean residual bottom drift ranged 04). 17 km/d. Effects of the cooling water intakes and heated effluents of local power plants on the overall circulation need quantitative investigation. Naval Ocean Systems Center, San Diego, Calif. 92152, USA. (isz) 82:5917 Heathershaw, A.D., 1982. Some observations of currents in shallow water during a storm surge. Estuar. coast. Shelf Sci., 14(6):635-648.
During a storm surge in Swansea Bay (Bristol Channel), residual flows may be five times higher than during quiescent flow periods. The observed flow regime suggests that while the residual circulation may be influenced by strong SW winds blowing onshore, offshore winds from the N W have a more significant effect, possibly as a result of wind-induced setdown in the bay head. Observed bottom currents can be predicted by a simple constant eddy viscosity model in which tidal mixing is dominant. Inst. of Oceanogr. Sci., Taunton, Somerset, UK. 82:5918 Mariette, V., G. Rougier, J.C. Salomon and B. Simon, 1982. Tidal currents in the Mer d'lrolse [NW France]. Oeeanologica Acta, 5(2): 149-159. (In French, English abstract.)
Tidal observations from British and French ports and from open sea points were used in a mathematical model that permitted calculation of currents for every nautical mile in the area and for every 3 minutes of time. Results were generally satisfactory although comparison between measured and calculated currents is difficult. Univ. de Bretagne