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Posted December 02, 2018 09:07:33 Photo: High temperatures are forecast for Sunday. (ABC News: Shelley Lloyd) Residents in bushfire-affected areas of Queensland are being reminded to stay alert, with temperatures in parts of the state set to soar into the mid-40s today. Key points: Fire crews bracing for a testing 24-48 hours, with no rain…

The summer of 2023 saw a surprising increase in global temperatures, even within the context of the ongoing greenhouse gas-driven warming trend. Many scientists were flummoxed. Their simulations didn't show this kind of spike.

As global temperatures rise and arctic ice melts, more ships are taking advantage of expedient, yet dangerous ocean routes that are opening in the polar region.

Coast guard leaders from the U.S., Russia and other Arctic nations are meeting to strengthen cooperation in northern seas, where warming temperatures are opening new waterways to boat traffic.

President Donald Trump will meet Saturday with Chinese President Xi Jinping in Buenos Aires. | Amilcar Orfali/Getty Images South China Morning Post Language used in statements issued after the two leaders meet will offer clues as to the temperature in the room - so what does it all mean? By TEDDY NG I SOUTH CHINA…

Transportation and warmer ocean temperatures could play a role.

* Anadromous Dolly Varden from Canada's Arctic enter the BEAUFORT Sea in approximately mid-June. * Canadian Dolly Varden occupy offshore areas of the BEAUFORT Sea. * Location of sea-ice and 5-10 °C sea surface temperatures affects species spatial distribution. * Plume from large MacKENZIE Delta influences marine habitat-use. * Species distribution overlaps conservation, oil and gas lease, and shipping areas

Internal seawater systems (ISS) are critical to the proper functioning of maritime vessels. Sea water is pumped on board ships for a broad array of uses, primarily for temperature control (e.g., engine and electrical systems), cooling capacity (e.g., air conditioners and refrigeration), and water provision (e.g., drinking, firefighting, steam, and ballast). Although sea water may spend only a brief period within ISS of a vessel, it can carry microorganisms and larval stages of macroorganisms throughout the system leading to biofouling accumulation that can impair system function or integrity. ISS can also act as a sub-vector of species translocations, potentially facilitating biological invasions. This review describes ships' ISS with a focus on operational impacts of biofouling and current drivers and barriers associated with ISS biofouling management. As ISS internal components are difficult to access, reports and studies of ISS biofouling are uncommon and much of the dedicated literature is decades old. The impact of biofouling on ISS and vessel operations is based on increased surface roughness of pipework and equipment, restricted water flow, corrosion and subsequent component impingement, reduced surface functional efficiency, and potential contamination by pathogens that can affect human and aquatic animal health. Biofouling management is primarily achieved using antifouling coatings and marine growth prevention systems, but independent and accessible data on their efficacy in ISS remain limited. Further research is required to resolve the extent to which biofouling occurs in ISS of the modern commercial fleet and the efficacy of preventive systems. Such information can ultimately inform decisions to improve operational efficiency for vessel operators and ensure any biosecurity risks are appropriately managed.

Marine environmental DNA (eDNA) is an important tool for biodiversity research and monitoring but challenges remain in scaling surveys over large spatial areas, and increasing the frequency of sampling in remote locations at reasonable cost. Here we demonstrate the feasibility of sampling from commercial vessels (Mediterranean ferries) while underway, as a strategy to facilitate replicable, systematic marine eDNA surveys in locations that would normally be challenging and expensive for researchers to access. Sixteen eDNA samples were collected from four fixed sampling stations, and in response to four cetacean sightings, across three cruises undertaken along the 300 km ferry route between Livorno (Tuscany) and Golfo Aranci (Sardinia) in the Ligurian/Tyrrhenian Seas, June-July 2018. Using 12SrDNA and 16SrDNA metabarcoding markers, we recovered diverse marine vertebrate Molecular Operational Taxonomic Units (MOTUs) from teleost fish, elasmobranchs, and cetaceans. We detected sample heterogeneity consistent with previously known variation in species occurrences, including putative species spawning peaks associated with specific sea surface temperature ranges, and increased night time abundance of bathypelagic species known to undertake diel migrations through the water column. We suggest commercial vessel based marine eDNA sampling using the global shipping network has potential to facilitate broad-scale biodiversity monitoring in the world's oceans.

Sound speed distribution, represented by a sound speed profile (SSP), is of great significance because the nonuniform distribution of sound speed will cause signal propagation path bending with Snell effect, which brings difficulties in precise underwater localization such as emergency rescue. Compared with conventional SSP measurement methods via the conductivity-temperature-depth (CTD) or sound-velocity profiler (SVP), SSP inversion methods leveraging measured sound field information have better real-time performance, such as matched field process (MFP), compressed sensing (CS) and artificial neural networks (ANN). Due to the difficulty in measuring empirical SSP data, these methods face with over-fitting problem in few-shot learning that decreases the inversion accuracy. To rapidly obtain accurate SSP, we propose a task-driven meta-deep-learning (TDML) framework for spatio-temporal SSP inversion. The common features of SSPs are learned through multiple base learners to accelerate the convergence of the model on new tasks, and the model's sensitivity to the change of sound field data is enhanced via meta training, so as to weaken the over-fitting effect and improve the inversion accuracy. Experiment results show that fast and accurate SSP inversion can be achieved by the proposed TDML method.

Warming temperatures and melting sea ice increase fog in the Arctic, creating a costly obstacle for trans-arctic shipping.

A new study in Science Advances led by UMBC's Tianle YUAN used satellite data from 2003 - 2020 to determine the effect of fuel regulations on pollution from cargo ships. The research team's data revealed significant changes in sulfur pollution after regulations went into effect in 2015 and 2020. Their extensive data set can also contribute to answering a bigger question: How do pollutants and other particles interact with clouds to affect global temperatures overall?

Surface atmospheric temperatures over the Arctic Ocean are rising faster than the global average, and sea-ice coverage has declined, making some areas newly accessible to ocean-going ships. Even so, Arctic waters remain hazardous to ships, in part, because of the highly variable nature of sea-ice formation and drift in some areas. In this study, we investigated interannual variability in polar class (PC) ship accessibility in the northern BERING Sea and seas north of the BERING Strait (East Siberian, Chukchi, Beaufort) from February 2012 to February 2022. We used sea-ice charts from the U.S. National Ice Center and calculations of the Risk Index Outcome (RIO) for PC3, PC5, and PC7 ships to characterize spatiotemporal trends in PC ship accessibility during the months of February, June, September, and November over the last 10 to 11 years. We also characterized shipping activity on select days in 2021. Overall, PC ship accessibility during the months of February and June increased over the last decade, especially for PC7 ships. However, areas that became more accessible over time did not support heavy ship traffic, possibly because they were not located on preferred transit routes or because they were surrounded by unnavigable ice, which made them inaccessible in practice. Ship accessibility was highly variable in the northernmost, offshore regions of the study site. During June, PC7 ship accessibility was interannually variable in waters south of the BERING Strait, and ships were active in those regions (most were fishing vessels), indicating potentially hazardous conditions during this time of year. Accessibility was considerably less variable over space and time (months, years) for PC5 (ice capable) ships and for PC3 ships (heavy icebreakers). Information from this study can be used by PC ship operators planning safe and successful shipping routes and by coastal states preparing emergency services to protect the maritime community. As governments and the private se

Promoting the sustainable development of marine environments requires planning, just as we have long had spatial planning for land-based activities. Now researchers from the University of Gothenburg and elsewhere are showing that marine planning must take climate change into consideration - something that it does not currently do. The researchers' models show that changes to temperature and salt content may impact ecosystems and species as much as all other effects on the environment combined.

Although shipping is a relatively energy-saving and environmentally friendly mode of transportation, the growth rate of its energy consumption and carbon emissions far exceeds that of other industries. As an important response to climate change, shipping decarbonization is not only an important part of achieving the temperature control goal of the Paris Agreement but is also an important direction for the future development of China's ecological civilization construction. China has formulated and promulgated legislation and policies on shipping decarbonization both at the national and local levels. The proposal in 2020 of the goal of carbon peaking and carbon neutrality has accelerated this process. In this context, this paper aims at reflecting on legislation and policies for decarbonization of shipping under China's "double carbon" target, and proposing suggestions for improvement. Firstly, we systematically review China's legislation and policies on shipping decarbonization to outline the normative system of China's shipping carbon reduction. Secondly, this paper evaluates China's legislation and policies on shipping decarbonization from the perspective of both achievements and challenges. Finally, this paper proposes that China's legislation and policies for decarbonization of shipping should be further improved from two aspects: enhancing mandatory force and expanding normative content.

Since the industrial revolution the ocean has become noisier. The global increase in shipping is one of the main contributors to this. In some regions, shipping contributed to an increase in ambient noise of several decibels, especially at low frequencies (10 to 100 Hz). Such an increase can have a substantial negative impact on fish, invertebrates, marine mammals and birds interfering with key life functions (e.g. foraging, mating, resting, etc.). Consequently, engineers are investigating ways to reduce the noise emitted by vessels when designing new ships. At the same time, since the industrial revolution (starting around 1760) greenhouse gas emissions have increased the atmospheric carbon dioxide fraction x(CO2) by more than 100 μmol mol-1. The ocean uptake of approximately one third of the emitted CO2 decreased the average global surface ocean pH from 8.21 to 8.10. This decrease is modifying sound propagation, especially sound absorption at the frequencies affected by shipping noise lower than 10 kHz, making the future ocean potentially noisier. There are also other climate change effects that may influence sound propagation. Sea surface warming might alter the depth of the deep sound speed channel, ice melting could locally decrease salinity and more frequent storms and higher wind speed alter the depth of the thermocline. In particular, modification of the sound speed profile can lead to the appearance of new ducts making specific depths noisier. In addition, ice melting and the increase in seawater temperature will open new shipping routes at the poles increasing anthropogenic noise in these regions. This review aims to discuss parameters that might change in the coming decades, focusing on the contribution of shipping, climate change and economic and technical developments to the future underwater soundscape in the ocean. Examples are given, contrasting the open ocean and the shallow seas. Apart from the changes in sound propagation, this review will also d