Eurasian Large-Scale Hazes in Summer 2016

Izvestiya, Atmospheric and Oceanic Physics - The technique for constructing the spatial distribution of maximum aerosol optical depth (MAOD) has been used to estimate the optically dense haze...     

Reflection of long internal waves of small amplitudes from an underwater slope

The dynamics of long waves in the vicinity of a transition point of a two-layer flow into a single-layer one is studied within the linear theory of shallow water. The analogy between this problem and the classical problem of surface wave runup on the shore is shown. Conditions for breaking internal waves on a slope are discussed.     

Hydrophysical state of the Large Aral Sea in the autumn of 2013: Thermal structure,currents, and internal waves

This paper is focused on the hydrophysical state of the western basin of the Large Aral Sea in its present conditions of ecological crisis. The investigation is based on the direct observations carried out during a field survey in the Aral Sea in October of 2013. The analysis of the distribution of the temperature values across the western basin is given. Time series of the water currents variability were recorded at four mooring stations. The pattern of the basin-scale circulation response to the wind forcing was described. Based on the in situ measurements of the time variability of the temperature fields, the principal characteristics of the internal waves were specified for the present-day Aral Sea for the first time.     

Analysis of the economic benefits associated with the recovery of threatened marine mammal species in the Canadian St. Lawrence Estuary

This paper examines Canadians' willingness to pay to recover the populations of three marine mammal species found in the St Lawrence Estuary. The valuation approach utilized a stated preference tool that is somewhat a hybrid between contingent valuation and a choice experiment with multiple species recovery program options and choices framed as referenda. Program options involved the use of a marine protected area and restrictions on whale watching and shipping industries. The estimated willingness to pay (WTP) for different levels of marine mammal recovery ranged from $77 to $229 per year per household and varied according to the species affected and the recovery program effort. A series of tests revealed that people would be willing to pay more for programs that contribute to greater increases in marine mammal populations, but the additional value of programs that improve a species status beyond the “at risk” threshold is relatively small.     

Applicability of Individual Transferable Quotas (ITQs) in Japanese fisheries: A comparison of rights-based fisheries management in Iceland, Japan, and United States

ITQs have not yet been introduced by the Government of Japan. In coastal areas, fishery cooperative associations have traditionally played an important role in managing fisheries through self-imposed rules and peer-monitoring systems. Recently, however, the economic competitiveness of Japanese fisheries in the international market is being questioned. In this paper, a detailed examination of the pros and cons of the current system in Japan is compared to the current fishery management measures of Iceland and the United States, where attaining economically or biologically efficient outcomes may be prioritized in making fisheries management decisions. For many coastal fisheries in Japan, maintaining a management scheme in which stakeholders play an active role in determining fisheries measures seems more relevant if their priority is to maintain the stability of coastal communities and equity of stakeholders. Intensive dialog among stakeholders would be necessary to identify shared objectives of their fishery operations and to make decisions to establish specific steps toward the goal of increasing economic efficiency, environmental sustainability, or stability of communities and equity of stakeholders.     

The first network of marine protected areas (MPAs) in the high seas: The process, the challenges and where next

Marine protected areas (MPAs) are increasingly being established to protect and rebuild coastal and marine ecosystems. However, while the high seas are increasingly subject to exploitation, globally few MPAs exist in areas beyond national jurisdiction. In 2010 a substantial step forward was made in the protection of high seas ecosystems with 286,200 km² of the North-East Atlantic established as six MPAs. Here a summary is presented of how the world's first network of high seas marine protected areas was created under the OSPAR Convention, the main challenges and a series of key lessons learned, aiming to highlight approaches that also may be effective for similar efforts in the future. It is concluded that the designation of these six MPAs is just the start of the process and to achieve ecological coherence and representativity in the North-East Atlantic, the network will have to be complemented over time by additional MPA sites.     

Computerized detection of seamounts from Seasat type geodetic data

Abstract

Geoid heights and vertical deflections derived from satellite radar altimetry contain characteristic signals that may be reproduced and explained by simple models for seamount gravitation acting on the sea surface. Computer algorithms capable of automatic operation and able to detect, approximately locate, and estimate parameters constraining the shape of actual sea‐mounts were written and tested. The computer program which utilized a digital high‐pass filter combined with a roughness sensor was effective in separating the seamount produced geoid undulation/vertical deflection pattern from the remaining data track features, simultaneously detecting and locating along the track such signals. Tests of the algorithm on several SEASAT passes over known bathymetry produced mixed results. Meaningful shape constraints were obtained by matching the geoid anomaly calculated from the seamount model to the actual mean sea level pattern for some seamounts. Results for other seamounts were poor and possible reasons for the failure are discussed. It is concluded that a computerized seamount detection program for radar altimetry data is feasible, but it will have to be more complex than the present one for fully successful operation.     

Accurate GPS measurement of the location and orientation of a floating platform

Abstract

This article describes the design and initial tests of the GPS portion of a system for making seafloor geodesy measurements. In the planned system, GPS antennas on a floating platform will be used to measure the location of an acoustic transducer, attached below the platform, which interrogates an array of transponders on the seafloor. Since the GPS antennas are necessarily some distance above the transducer, a short‐baseline GPS interferometer consisting of three antennas is used to measure the platform's orientation.

A preliminary test of several crucial elements of the system was performed at the Scripps Institution of Oceanography (SIO) in December 1989. The test involved a fixed antenna on the pier and a second antenna floating on a buoy about 80 m away. GPS measurements of the vertical component of this baseline, analyzed independently by two groups using different software, agree with each other and with an independent measurement within a centimeter.

The first test of an integrated GPS/acoustic system took place in the Santa Cruz Basin off the coast of southern California in May 1990. In this test a much larger buoy, designed and built at SIO, was equipped with three GPS antennas and an acoustic transducer that interrogated a transponder on the ocean floor. Preliminary analysis indicates that the horizontal position of the transponder can be determined with a precision of about a centimeter. Further analysis will be required to investigate the magnitude of systematic errors.