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On the processes of renewal of the North Atlantic deep water in the Irminger Sea
748
Oceanographic Abstracts
measured in and around the nets with a thermister-type current meter. Observations were also made o n the shape of the nets in situ and the stream-lines. The current velocities inside the net were mostly equal to, or somewhat faster than, those at the mouth. As compared to the latter, slower speeds were nearly always measured close to the outer surfaces of the net, along the sides and on the rear. The influx of water running towards the sides of the net can be divided into two parts. The major one passes out through the meshes and is transformed into eddies along the outside of the net, with a gradually reduced speed. The minor part continues to run along the inside of the net and accelerates the current velocity in the core of the net. The current velocity at any given point inside the net is theoretically given in the following formula : A o V 0 - - ( A 0 - - A ) F" 1/ A W CSsin 0 where, Ao is the area of the net mouth, 11"0the current velocity at the net mouth, A the cross area of the net as a given point inside the net C a coetticient of the current velocity at a mesh, S the total area of meshes per unit length, 0 the angle of inclination of the net against the current direction, and V' denotes the average current velocity outside the net. The values calculated after the formula roughly coincide with the measurements. HmSCH P. and A. M. CARTER, 1965. Mathematical models for the prediction of SOFAR propagation effects. J. Acoust. Soc. Amer., 37 (1): 90-94. Various analytical models for the acoustic speed-versus-depth profile of the ocean near the soundchannel axis are examined with a view toward predicting the characteristic features of SOFAR transmission, especially the time dispersion of the multiple SOFAR arrivals. It is found that these features are accounted for only by very specific models. In particular the one analytically tractable model that leads to the observed results appears to be given by : c 2 = c 0 2 ( 1 - 1 ~ z l ~ ) -1, w i t h l < / 3 < 2 . Hot.z~ F., G. ~ u s E and G. Sir~tza, 1964. On the processes of renewal of the North Atlantic deep water in the Irminger Sea. Deep-Sea Res., 11 (6): 881-890. Observations o f temperature and electrical conductivity by a recording, in situ salinometer are discussed in respect to the physical processes connected with the renewal of North Atlantic deep water. The measured fine structure of the layering suggests that the downward movement of cooled surface water is combined with horizontal mixing down to more than 1000 m depth. This is confirmed by the existence of water elements which have slightly different temperature and salinity. Curves of temperature, conductivity, and salinity and T - S diagrams are shown. HtrNrdr~s K. L., 1965. Tide and storm surge observations in the Chukchi Sea. Limnol. Oceanogr., 10 (1): 29-39. Sea level heights were recorded with a tide gauge at Fletcher's Ice Island (T-3) while it was aground in the Chukchi Sea at 71 ° 55'N lat, 160° 20'W long. Harmonic analyses of the data were made for five tidal components. The tidal hour (M2) was 9.11 at this location, in good agreement with the cotidal chart of Sverdrup (1926). Mean spring tide range was 12.5 cm. Storm surges at this location on the continental shelf had a range of about 40 cm. During relatively stationary atmospheric conditions, the storm surge heights tended to follow the inverted barometer. However, under moving pressure systems, the storm surge heights developed an asymmetry that deviated from the inverted barometer. A one-dimensional flow model with characteristics similar to a profile through the storm provides some understanding of these asymmetric storm surge heights. J~SSEN A., 1964. Chandier's period in the mean sea level. Tellus, 16 (4): 513-516. The constants of the Chandierian oscillation in the mean sea level are calculated for nine ports a n d the results compared with those of the International Latitude Service. The Chandler period is clearly observed and the amplitudes are large enough. The phase differences greatly depend upon the selected localities. I~r, rDIG P. M. and H. J. Cr.ARr~, 1965. Experimental liquid-filled transducer array for deepocean operation. J. Acoust. Soc., Amer., 37 (1): 99-104. A small experimental transducer array was designed, constructed, and tested to demonstrate the feasibility of enclosing the elements in a liquid-filled housing that requires no pressure-release materials. The transducer consists of four dumbell-type, lead zirconate titanate transducer elements t h a t are set in close-fitting cavities in a high pc metal block. The entire housing is filled with a silicone fluid and provision is made to maintain the inside pressure equal to the pressure on the outside at all times. Presentation of frequency-response curves, electrical-input impedances, and efficiencies demonstrate that the transducer characteristics are relatively insensitive to ambient pressures up to 1000psi, the maximum pressure available for test. The transducer is further
Oceanographic Abstracts
measured in and around the nets with a thermister-type current meter. Observations were also made o n the shape of the nets in situ and the stream-lines. The current velocities inside the net were mostly equal to, or somewhat faster than, those at the mouth. As compared to the latter, slower speeds were nearly always measured close to the outer surfaces of the net, along the sides and on the rear. The influx of water running towards the sides of the net can be divided into two parts. The major one passes out through the meshes and is transformed into eddies along the outside of the net, with a gradually reduced speed. The minor part continues to run along the inside of the net and accelerates the current velocity in the core of the net. The current velocity at any given point inside the net is theoretically given in the following formula : A o V 0 - - ( A 0 - - A ) F" 1/ A W CSsin 0 where, Ao is the area of the net mouth, 11"0the current velocity at the net mouth, A the cross area of the net as a given point inside the net C a coetticient of the current velocity at a mesh, S the total area of meshes per unit length, 0 the angle of inclination of the net against the current direction, and V' denotes the average current velocity outside the net. The values calculated after the formula roughly coincide with the measurements. HmSCH P. and A. M. CARTER, 1965. Mathematical models for the prediction of SOFAR propagation effects. J. Acoust. Soc. Amer., 37 (1): 90-94. Various analytical models for the acoustic speed-versus-depth profile of the ocean near the soundchannel axis are examined with a view toward predicting the characteristic features of SOFAR transmission, especially the time dispersion of the multiple SOFAR arrivals. It is found that these features are accounted for only by very specific models. In particular the one analytically tractable model that leads to the observed results appears to be given by : c 2 = c 0 2 ( 1 - 1 ~ z l ~ ) -1, w i t h l < / 3 < 2 . Hot.z~ F., G. ~ u s E and G. Sir~tza, 1964. On the processes of renewal of the North Atlantic deep water in the Irminger Sea. Deep-Sea Res., 11 (6): 881-890. Observations o f temperature and electrical conductivity by a recording, in situ salinometer are discussed in respect to the physical processes connected with the renewal of North Atlantic deep water. The measured fine structure of the layering suggests that the downward movement of cooled surface water is combined with horizontal mixing down to more than 1000 m depth. This is confirmed by the existence of water elements which have slightly different temperature and salinity. Curves of temperature, conductivity, and salinity and T - S diagrams are shown. HtrNrdr~s K. L., 1965. Tide and storm surge observations in the Chukchi Sea. Limnol. Oceanogr., 10 (1): 29-39. Sea level heights were recorded with a tide gauge at Fletcher's Ice Island (T-3) while it was aground in the Chukchi Sea at 71 ° 55'N lat, 160° 20'W long. Harmonic analyses of the data were made for five tidal components. The tidal hour (M2) was 9.11 at this location, in good agreement with the cotidal chart of Sverdrup (1926). Mean spring tide range was 12.5 cm. Storm surges at this location on the continental shelf had a range of about 40 cm. During relatively stationary atmospheric conditions, the storm surge heights tended to follow the inverted barometer. However, under moving pressure systems, the storm surge heights developed an asymmetry that deviated from the inverted barometer. A one-dimensional flow model with characteristics similar to a profile through the storm provides some understanding of these asymmetric storm surge heights. J~SSEN A., 1964. Chandier's period in the mean sea level. Tellus, 16 (4): 513-516. The constants of the Chandierian oscillation in the mean sea level are calculated for nine ports a n d the results compared with those of the International Latitude Service. The Chandler period is clearly observed and the amplitudes are large enough. The phase differences greatly depend upon the selected localities. I~r, rDIG P. M. and H. J. Cr.ARr~, 1965. Experimental liquid-filled transducer array for deepocean operation. J. Acoust. Soc., Amer., 37 (1): 99-104. A small experimental transducer array was designed, constructed, and tested to demonstrate the feasibility of enclosing the elements in a liquid-filled housing that requires no pressure-release materials. The transducer consists of four dumbell-type, lead zirconate titanate transducer elements t h a t are set in close-fitting cavities in a high pc metal block. The entire housing is filled with a silicone fluid and provision is made to maintain the inside pressure equal to the pressure on the outside at all times. Presentation of frequency-response curves, electrical-input impedances, and efficiencies demonstrate that the transducer characteristics are relatively insensitive to ambient pressures up to 1000psi, the maximum pressure available for test. The transducer is further