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This paper presents a geometric stochastic channel model designed for analyzing maritime communication and navigation services between moving ships using the C-band or sub-6 GHz spectrum, which aligns with the focus of emerging 5G networks on land. The channel model is validated through channel measurements conducted both on the sea and land. A software tool has been developed to integrate and analyze these measurements, which is included with this publication. The main challenge in developing the channel model for maritime services lies in the dynamic nature of the sea surface, leading to constantly changing reflection conditions due to varying reflectors and scatterers on the water. Additionally, the motion conditions of the transmitter and receiver on ships change in all three dimensions, depending on the sea state. To address these complexities, data from several measurement campaigns in diverse areas were collected. The analysis involved examining the propagation conditions over the sea with variations in sea surface roughness, antenna heights, and used bandwidths. Moreover, additional propagation conditions over nearby land were also taken into account. The study demonstrates that the changing antenna height on the ship, influenced by sea conditions, significantly affects the reflection and scattering conditions. The research aims to develop reliable, high-data rate, and broadband marine communication systems. Therefore, a measurement bandwidth of 120MHz was employed to derive the propagation model. This model not only offers absolute timing information but can also be used for time-based ranging or positioning systems. The proposed geometric stochastic channel model provides valuable insights into the complex maritime communication and navigation environment. By accounting for the continuously evolving sea surface and its impact on antenna height, the model offers a robust framework for studying and optimizing marine communication systems. The availability of

A new paper from WCS (Wildlife Conservation Society), in partnership with researchers and practitioners from National Oceanic and Atmospheric Administration, U.S. Coast Guard, Space Quest, Google, and SkyTruth, reviews the use of a maritime vessel communication and navigational safety system that is not only effective in protecting people, but wildlife such as whales, walruses, and other wildlife species as well. With improvements, say the authors, the system will ultimately result in greater engagement by vessel companies and operators in the conservation of marine resources.

The IMO's sub-committee on Navigation, Communications and Search and Rescue will meet on February 29, and the International Maritime Rescue Federation (IMRF) is asking the committee to consider some important changes to search and rescue requirements.

The Protocol on Environmental Protection of the Antarctic Treaty stipulates that the protection of the Antarctic environment and associated ecosystems be fundamentally considered in the planning and conducting of all activities in the Antarctic Treaty area. One of the key pollutants created by human activities in the Antarctic is noise, which is primarily caused by ship traffic (from tourism, fisheries, and research), but also by geophysical research (e.g., seismic surveys) and by research station support activities (including construction). Arguably, amongst the species most vulnerable to noise are marine mammals since they specialize in using sound for communication, navigation and foraging, and therefore have evolved the highest auditory sensitivity among marine organisms. Reported effects of noise on marine mammals in lower-latitude oceans include stress, behavioral changes such as avoidance, auditory masking, hearing threshold shifts, and-in extreme cases-death. Eight mysticete species, 10 odontocete species, and six pinniped species occur south of 60°S (i.e., in the Southern or Antarctic Ocean). For many of these, the Southern Ocean is a key area for foraging and reproduction. Yet, little is known about how these species are affected by noise. We review the current prevalence of anthropogenic noise and the distribution of marine mammals in the Southern Ocean, and the current research gaps that prevent us from accurately assessing noise impacts on Antarctic marine mammals. A questionnaire given to 29 international experts on marine mammals revealed a variety of research needs. Those that received the highest rankings were (1) improved data on abundance and distribution of Antarctic marine mammals, (2) hearing data for Antarctic marine mammals, in particular a mysticete audiogram, and (3) an assessment of the effectiveness of various noise mitigation options. The management need with the highest score was a refinement of noise exposure criteria. Environment

Beluga whales are highly social and vocal marine mammals. They use acoustics to navigate, find prey, avoid predators and maintain group cohesion. For Alaska's critically endangered COOK Inlet beluga population, these crucial communications may compete with a cacophony of noise from human activities.

China to enhance communication ability in Northeast Passage of Arctic.

One direct consequence of Arctic warming is the expansion of navigable portions of the Arctic Ocean. As a result, vessel traffic and the accompanying threats of spills, strikes and disturbance is intensifying throughout the Arctic. In the BERING Sea, these threats to the environment, wildlife and to the people who rely on marine resources for food and cultural continuity, are acute. We examined the spatial relevance of an Area To Be Avoided (ATBA), a shipping-risk mitigation measure, established around St. Lawrence Island with respect to seabirds, as sentinel species, habitat use. We studied four seabird species (common murre Uria aalge, thick-billed murre U. lomvia, crested auklet Aethia cristatella, black-legged kittiwake Rissa tridactyla) breeding at St. Lawrence Island in the northern BERING Sea. GPS tracking data from 47 at-sea foraging trips showed that both murre species and crested auklets distributed outside the ATBA, during at least one stage of the breeding season. A larger dataset based on the birds' red blood cell isotopic signatures confirmed that for murres, the tracked individuals covered the broad niche exploited by these species. Habitat modelling further showed that the birds' most suitable marine habitats were associated with seasonal surface chlorophyll blooms, and largely extended beyond the ATBA on the shelf north of the island. Data on the murres' diet and diving behavior emphasized the importance of the shelf as a foraging habitat for these birds. We suggest that extending the ATBA to the north by only 35 km, would include areas of maximal habitat suitability. This extension would better protect seabirds, their foraging habitats and the cultural continuity of St. Lawrence Islanders, against growing threats stemming from Arctic warming.

Horror on the High Seas.

'Pirates' raid Japanese trawler off Peru coast.