An analytical study of measured radiometric data. Volume 2 - Sea water data
Microwave radiometer analysis of sea water, salines, quartz sand, and crushed limestone - sea water plots and printout
Porter, R. A.↗
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Study of the possible role of pollution in the prevalence of sea nettles in the Chesapeake Bay and the development of a census taking method
A study of the effect of pollutants on the sea nettle population of Chesapeake Bay was conducted. The effects of pollutants on the polyp stage of the nettle were stressed. Methods of detecting adult sea nettles by remote sensing are discussed. The effects of phosphate, nitrate, ammonium, and combinations of these pollutants were investigated.
Source record↗
Aircraft measurements of microwave emission from Arctic Sea Ice
Measurements of the microwave emission from Arctic Sea ice were made with aircraft at 8 wavelengths ranging from 0.510 cm to 2.81 cm. The expected contrast in emissivities between ice and water was observed at all wavelengths. Distributions of sea ice and open water were mapped from altitudes up to 11 km in the presence of dense cloud cover. Different forms of ice also exhibited strong contrasts in emissivity. Emissivity differences of up to 0.2 were observed between two types of ice at 0.811 cm wavelength. The higher emissivity ice type is tentatively identified as having been formed more recently than the lower emissivity ice.
Wilheit, T. T.↗
The stopping rate of negative cosmic-ray muons near sea level
A production rate of 0.065 + or - 0.003 Ar-37 atom/kg min of K-39 at 2-mwe depth below sea level was measured by sweeping argon from potassium solutions. This rate is unaffected by surrounding the solution by paraffin and is attributed to negative muon captures and the electromagnetic interaction of fast muons, and not to nucleonic cosmic ray component. The Ar-37 yield from K-39 by the stopping of negative muons in a muon beam of a synchrocyclotron was measured to be 8.5 + or - 1.7%. The stopping rate of negative cosmic ray muons at 2-mwe depth below sea level from these measurements and an estimated 17% electromagnetic production is 0.63 + or - 0.13 muon(-)/kg min. Previous measurements on the muon stopping rate vary by a factor of 5. Our value is slightly higher but is consistent with two previous high values. The sensitivity of the Ar-37 radiochemical method for the detection of muons is considerably higher than that of the previous radiochemical methods and could be used to measure the negative muon capture rates at greater depths.
Spannagel, G.↗
Use of a spacecraft borne altimeter for determining the mean sea surface and the geopotential
An experiment is proposed to test a first generation spacecraft-borne radar altimeter's capability to measure the topography of the sea surface. The initial radar altimeter will have an instrumental error of one meter and an overall accuracy to two to five meters. This instrument will thus improve the accuracy of the geoid from the present 10 to 20 meters to better than 5 meters. In order to detect storm surges, tidal forces, and ocean currents, an altimeter with an overall accuracy of at least ?1 meter will be required. The overall accuracy of the initial radar altimeter will thus primarily provide geodetic information and possible oceanographic information such as sea state.
Kahn, W. D.↗
Microwave emission of Arctic Sea ice
The feasibility of carrying microwave radiometers on Nimbus E and F missions for sea ice surveys was studied in the arctic using aircraft. It was found that passive microwave signatures of Arctic Sea ice relate specifically to the structure and type of ice. It is concluded that a new tool for conducting ice surveys from aircraft and satellites with remote sensors was discovered.
Gloersen, P.↗
Estimation of sea surface temperature from remote measurements in the 11-13 micron window region
The Nimbus-4 IRIS data was examined in the spectral region 775 to 1250/cm (8-13 microns) for useful information to determine the sea surface temperature. The high spectral resolution data of IRIS was degraded to low resolution by averaging to simulate a multi-channel radiometer in the window region. These simulated data show that within the region 775-975/cm (12.9-10.25 microns) the brightness temperatures are linearly related to the absorption parameters. Such a linear relationship is observed over cloudy as well as clear regions and over a wide range of latitudes. From this linear relationship it is feasible to correct for the atmospheric attenuation and get the sea surface temperature, accurate to within 1 K, in a cloud free field of view. The information about the cloud cover is taken from the TV pictures and BUV albedo measurements on board the Nimbus-4 satellite.
Prabhakara, C.↗
A multispectral method of determining sea surface temperatures
A multispectral method for determining sea surface temperatures is discussed. The specifications of the equipment and the atmospheric conditions required for successful multispectral data acquisition are described. Examples of data obtained in the North Atlantic Ocean are presented. The differences between the actual sea surface temperatures and the equivalent blackbody temperatures as determined by a radiometer are plotted.
Shenk, W. E.↗
Airway structure and alveolar emptying in the lungs of sea lions and dogs.
Investigation of the effects of various cycles of compression and decompression on the alveolar volumes of the excised lungs of sea lions and dogs. The results obtained include the finding that, in comparison to dog lungs, sea lion lungs empty more completely on mild compression and much more completely on severe compression. These findings support Scholander's (1940) hypothesis that some marine mammals are protected from decompression sickness by cartilaginous reinforcement of the small airways which permits alveolar emptying during a dive, so isolating compressed gas from pulmonary capillary blood.
Denison, D. M.↗
A multispectral technique to determine sea surface temperature using Nimbus 2 data.
Three channels of the Nimbus 2 five-channel Medium Resolution Infrared Radiometer have been employed in the development of a technique to determine sea surface temperature. Two of the channels in the 0.2-4.0 and 6.4-6.9 micron spectral regions are used to indicate a cloud-free line of sight and the third, a high signal-to-noise window channel (10-11 microns), measures the equivalent blackbody temperature (Tbb) which is a function of the thermal emission from the sea surface and the intervening atmosphere. Equivalent blackbody temperatures and normalized reflectance thresholds were established using frequency distributions from the 6.4-6.9 and 0.2-4.0 micron channels, respectively, to determine the existence of cloud-free conditions. The window Tbb's were compared with ship ocean temperature measurements for a one-month period over the western North Atlantic. This comparison revealed a plus or minus 1.5 K dispersion about the mean difference between the ship temperatures and window Tbb's between 31-34 N.
Shenk, W. E.↗
Radar pulse compression and high resolution sea reflectivity
The state-of-the-art in radar pulse compression as it applies to spacecraft altimetry is summarized. It is illustrated how in the next few years vertical resolutions to 0.5 to 2.0 ft. can be obtained with relative accuracies of 5 to 10% of these values if the nature of the sea surface is known. Data are also given that show when high accuracy is desired, second order effects such as the asymmetries in the sea surface reflectivity may be taken into account.
Nathanson, F. E.↗
Remote Sensing of Sea Ice from Earth Satellites
The application of meteorological satellite data for mapping ice fields is discussed. The characteristics of the photographic records of sea ice formations are described. The derivation of the composite minimum brightness chart by computer processing of the mapped satellite vidicon data for several successive days is explained. The factors which create a quantitative delimiting of the sea ice conditions are explained.
Mcclain, E. P.↗
Remote Sensing of Sea Surface Temperature from Earth Satellites
Techniques for measuring sea surface temperature using remote sensors in earth orbiting satellites are discussed. Specific reference is made to the infrared sensors carried by the TIROS Operational Satellite. The development of a method to examine a large number of measurements in order to differentiate the temperature effects of clouds is described. It is stated that the system used is completely objective and minimizes the influence of atmospheric absorption, cloud contamination, and instrumental noise on the inferred sea surface temperatures.
Rao, P. K.↗
Transequatorial effects of sea surface temperature anomalies in a global general circulation model
The global response of the atmosphere to a persistent anomalous pool of warm sea surface temperatures in the extratropical Pacific Ocean is examined in terms of the meridional pole-to-pole profile of the zonally-averaged 600 mb surface for periods up to 90 days. Following an initial hydrostatic inflation of the isobaric surface in the latitude of the warm pool, effects spread poleward within the hemisphere, then begin to appear after about two to three weeks in high latitudes of the opposite hemisphere, but with little or no response in the tropics. The same sea temperature anomaly field generates a stronger response in winter than in summer, and a very different reaction when located in the Southern Hemisphere than when in the Northern Hemisphere.
Spar, J.↗
Mapping Arctic sea ice from the Earth Resources Technology Satellite
The author has identified the following significant results. Methods of detecting ice and for distinguishing between ice and clouds are discussed, and examples of ERTS-1 data showing ice distributions in northern Hudson Bay, M'Clure Strait, the eastern Beaufort Sea, and the Greenland Sea are presented. The results of the initial analysis of ERTS-1 data indicate that the locations of ice edges and ice concentrations can be accurately mapped, and that considerable information on ice type can be derived through use of the various spectral bands. Ice features as small as 80 to 100 m width can be mapped.
Barnes, J. C.↗
Studies of the inner shelf and coastal sedimentation environment of the Beaufort Sea from ERTS-1
The author has identified the following significant results. Northward flowing rivers of Alaska inundate extensive areas of sea ice during spring breakup. This process has been studied under the ERTS-1 program. Drainage of large volumes of fresh water through the ice at holes and cracks (strudel) causes scour depressions, over 4 m deep, and up to 20 m across in the sea floor below. Strudel scours occur within 30 km of river mouths, generally in areas where ERTS-1 imagery shows less potential for drifting ice to scour the bottom than elsewhere. The shapes and distribution patterns of strudel scours correspond with those of strudel seen in the ice canopy. Densities of scours are highest in the inner areas of overlfow. But strudel scours also occur outside of overflow areas mapped during the last several years. These must be very old. One strudel scour investigated by diving is surrounded by a rim, has vertical walls exposing a tundra horizon, and terminates at a gravel layer 4 m below the lagoon floor. Another terminates at a semi-consolidated layer of silty clay. The gravel and silty clay are pre-Holocene deposits. Mixing of Holocene marine with older sediments by vertical strudel flow causes great variability in sediment types over small areas. These observations complicate interpretation of shallow water deposits of cold climates.
Reimnitz, E.↗
Synthetic sea water - An improved stress corrosion test medium for aluminum alloys
A major problem in evaluating the stress corrosion cracking resistance of aluminum alloys by alternate immersion in 3.5 percent salt (NaCl) water is excessive pitting corrosion. Several methods were examined to eliminate this problem and to find an improved accelerated test medium. These included the addition of chromate inhibitors, surface treatment of specimens, and immersion in synthetic sea water. The results indicate that alternate immersion in synthetic sea water is a very promising stress corrosion test medium. Neither chromate inhibitors nor surface treatment (anodize and alodine) of the aluminum specimens improved the performance of alternate immersion in 3.5 percent salt water sufficiently to be classified as an effective stress corrosion test method.
Humphries, T. S.↗
Sea ice and surface water circulation, Alaskan Continental Shelf
The author has identified the following significant results. The boundaries of land-fast ice, distribution of pack ice, and major polynya were studied in the vicinity of the Bering Strait. Movement of pack ice during 24 hours was determined by plotting the distinctly identifiable ice floes on ERTS-1 imagery obtained from two consecutive passes. Considerably large shallow area along the western Seward Peninsula just north of the Bering Strait is covered by land fast ice. This ice hinders the movement of ice formed in eastern Chukchi Sea southward through the Bering Strait. The movement of ice along the Russian coast is relatively faster. Plotting of some of the ice floes indicated movement of ice in excess of 30 km in and south of the Bering Strait between 6 and 7 March, 1973. North of the Bering Strait the movement approached 18 km. The movement of ice observed during March 6 and 7 considerably altered the distribution and extent of polynya. These features when continually plotted should be of considerable aid in navigation of ice breakers. The movement of ice will also help delineate the migration and distribution of sea mammals.
Wright, F. F.↗