Kategorie: News
Three industry sectors have the potential to sustainably reduce underwater noise in the oceans
The Convention on the Conservation of Migratory Species (CMS) today releases a technical report on preventing and reducing underwater noise pollution, prepared by OceanCare expert Dr Lindy Weilgart.
Today, on World Oceans Day, the Convention on the Conservation of Migratory Species (Bonn Convention, CMS) released a technical report that provides an overview of technologies and practices that can reduce noise emissions from activities of three industries. These are commercial shipping, the oil and gas industry during oil and gas exploration, and the wind energy industry during the construction of offshore wind farms.
Author Dr Lindy Weilgart, an expert on underwater noise at the international marine conservation organisation OceanCare and associate professor at Canada's Dalhousie University, examined best practice examples for this study. These convincingly demonstrate that a significant reduction of noise emissions at the source is possible.
The concept of promoting the use of "best available technologies and best environmental practices" has been accepted and supported by governments from around the world for many years under numerous multilateral environmental agreements. These include the Convention on Biological Diversity (CBD), the Bonn Convention, as well as regional agreements such as the UNEP Mediterranean Action Plan, the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Ocean (ACCOBAMS) and the Agreement on the Conservation of Small Cetaceans of the North Sea, Baltic Sea, North Atlantic Ocean and Irish Sea (ASCOBANS).
"There is ample evidence that underwater noise pollution is a problem for many marine species - to date, impacts on at least 150 species have been documented. Technologies that reduce noise at source can best mitigate these negative impacts. Governments, such as those in Germany, have imposed noise limits, spurring technological innovations for quieter alternatives," says Dr Lindy Weilgart.
Recommendations of the CMS report
To make ships quieter, it is important to minimise cavitation - first and foremost through better maintenance and optimised adaptation of the propeller design to the ship's hull. This often also improves efficiency. The greatest effect is achieved when noise reduction measures are applied to the 10-15 % of the noisiest container and cargo ships. At the operational level, the most effective and immediately implementable measure is to reduce sailing speed. Slower shipping reduces noise emissions and also has other environmental benefits. Specifically, current modelling suggests that a 10% reduction in the sailing speed of the global shipping fleet would reduce noise from shipping by 40%.
"Some noise reduction methods, including reducing sailing speed, have additional environmental benefits, for example by reducing the risk of collisions with whales. These methods should therefore be particularly encouraged," says Dr Lindy Weilgart. If a ship sails more slowly, it consumes less fuel and emits fewer greenhouse gases. Taking all factors into account - weather conditions, possibly additional ships for the same transport performance at a lower speed, etc. - the calculations show on average that a speed reduction of 10% and 20% reduces CO2 emissions by 13% and 24%, respectively.
For seismic prospecting, quieter technologies such as Marine Vibroseis (MV), which could replace sonic cannons, are very promising, as much of the energy emitted by so-called airguns (the mid and high frequencies) only causes harm, but no benefit. A controlled sound source such as Marine Vibroseis, tailored to specific environmental conditions and without the harmful explosiveness of airguns, would also likely be gentler on marine life. MV has been known about since 2008, but until now its use has hardly been advanced by the industry.
In contrast to the oil and gas industry, the renewable energy sector shows that many new noise reduction technologies are being applied - e.g. alternative concepts to pile driving for offshore wind power have been developed. This trend has been triggered by mandatory requirements from some governments, such as Germany: Noise limits were prescribed and thus an action-determining standard for innovations and investments was set.
"Using existing technologies and learning from best practice experiences in different regions should actually be a matter of course. Unfortunately, however, this is not the case. The good news is that examples show that innovation and investment in less harmful technologies can be stimulated, for example by governments setting binding targets to reduce negative impacts on species," comments Nicolas Entrup, Head of International Cooperation at OceanCare, on why reports like this are invaluable.
While the report addresses technologies that could reduce noise from seismic exploration for new oil and gas deposits, OceanCare reminds us that we need to think beyond such technologies. "In the context of an increasingly pressing climate emergency, the best environmental practice with regard to fossil fuels is to leave them in the ground. On the net zero path, no new oil and gas fields are needed, as stated by the International Energy Agency (IEA) in its Net Zero by 2050 report," says Carlos Bravo, Ocean Policy Expert at OceanCare.
The report can be accessed here: Best Available Technology (BAT) and Best Environmental Practice (BET) for Mitigating Three Noise Sources: Shipping, Seismic Airgun Surveys and Pile Driving.
Further information:
oceancare.org/meeresschutz/unterwasserlaerm/
oceancare.org/stories_and_news/kollisionen-schifffahrt/
oceancare.org/stories_and_news/oelsuche_trotz_klimakrise/
oceancare.org/stories_and_news/tiefseebergbau-wale-gefaehrden/
About OceanCare
OceanCare is committed to working with regulators, policy makers and the private sector to develop solution-oriented policies and practices. The organisation has partner status with the Bonn Convention and contributes to achieving the Convention's objectives.
ICP
On Monday 5 June, Dr Weilgart presented some of the report's key recommendations at the United Nations Open Informal Consultative Process (ICP) this week (5-9 June 2023) at the UN compound in New York, "New Maritime Technologies: Challenges and Opportunities" as its theme.
Nicolas Entrup, Director of International Cooperation, is also invited as a panelist to the ICP session to present the results of the SAvE Whales project and discuss the most effective methods to mitigate ship collisions with endangered whales.
IMO
The 80th meeting of the Marine Environment Protection Committee (MEPC) of the International Maritime Organization (IMO) will discuss and is expected to adopt the revised guidelines for reducing underwater noise emissions from shipping. In this context, the CMS technical report provides complementary information underpinning both the need and the potential options for effective implementation.
IEA
The IEA Roadmap contains more than 400 milestones to guide the path to global net zero emissions by 2050. This includes no investment in new fossil fuel projects from the date of its publication: "Net Zero by 2050. A Roadmap for the Global Energy Sector", May 2021 report.