The environmental impact of the Nord Stream leak

Sustainable Leaders | Europe

By Nicolette Thomson, Freelance writer

Published February 7th, 2023

On September 26th 2022, subsequent explosions on the Nord Stream 1 and 2 pipelines caused several large methane gas leaks in the Baltic Sea. This unprecedented leak has raised concerns in the international community about the event's environmental impact.

The twin Nord Stream pipelines can transport up to 55 billion cubic metres of natural gas per year, running 1,224 kilometres from Russia to Germany. Whilst the pipelines were closed during the time of the leak, due to the ongoing war in Ukraine, there was still enough gas stored to release up to 300,000 tonnes of methane into the atmosphere—making it the most significant anthropogenic release of methane gas in history.

The explosions on Nord Stream pipelines released methane gas into the Baltic Sea, which bubbled up to the surface, captured by satellite image. | © ESA/Rosetta/NavCam – CC BY-SA IGO 3.0, ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO, ESA/ Copernicus Sentinel-2

Using radar and optical imaging, satellites detected the gas bubbles at the surface of the Baltic Sea. The disturbances in the water measured from 500 to 700 metres in diameter. This area decreased slowly over a few days after the leak was first detected.

Three underwater robots were deployed by the University of Gothenburg to monitor the impacts of the gas in the surrounding area. In the short term, the methane leak will likely cause direct harm to the surrounding aquatic ecosystem through decreased oxygen intake by organisms. In the long term, however, this leak is just a drop in the bucket of the massive powerhouse of the energy industry.

The amount caused by the leak pales in comparison to the amount of methane released each year by the energy industry. According to the International Energy Agency (IEA), approximately 135 million tonnes of methane were estimated to have been released by the energy sector in 2021.

The underwater robots collected data on how the chemicals in the sea change due to the methane leak. For fifteen weeks, they monitored salinity, temperature, and the amount of chlorophyll and oxygen content in the water. Additionally, one of the three robots monitored the methane levels. Two of the three robots have remained in the water and will continue to monitor the water quality.

‘Approximately 135 million tonnes of methane were estimated to have been released by the energy sector in 2021.’

All of this information will help scientists paint a clear picture of how the water and wildlife are affected. However, it may take some time before we can understand the ramifications of this vast release of methane gas.

The construction of the Nord Stream 2 pipeline was vehemently opposed by the West and several European countries. Latvia and Poland were particularly vocal out of fear that the pipeline would create destabilising geopolitical consequences, such as by making the role of Eastern European pipeline transit states redundant.

Its construction doubled the natural gas imports from Russia to the EU, giving Russia control over a large portion of the European gas market and tilting the power of energy in their favour. In 2009, Ukraine experienced a nationwide gas crisis due to the halt of gas exports from Russia—a move that Russia has mirrored with its recent actions. Russia has cut-off large amounts of gas supplies to Europe in response to the sanctions put in place due to the ongoing conflict in Ukraine.

A recent investigation has claimed that the explosions on the Nord Stream pipelines may have been caused by the Russian government, in an attempt to sabotage further energy supply to Europe. To better understand what was in the water at the time of the leak, sources have told CNN that the United States is considering using advanced sonar reading technology to analyse audio recordings of the site from the time of the explosion.

This claim has been strongly denied by Russian officials—raising an important question, how do we hold countries accountable for the deliberate destruction of the environment?

Countries are working together to investigate the cause of the Nord Stream pipeline methane leaks. | Markus Winkler / Unsplash

As we move closer to a green-powered world, natural gas has been hailed as a vital transition energy source, as it releases less carbon during production compared to coal or oil. However, The IEA warns that gas stores are expected to decrease from 95% full in 2022 to 65% full in 2023. Immediate actions must be taken towards increasing energy efficiency and expanding renewable energy markets, in order to lessen the reliance on natural gas from international countries.

Additionally, despite being regarded as ‘cleaner’ than coal or oil, any methane that has leaked from Nord Stream natural gas pipeline will have further contributed to the greenhouse gas (GHG) effect, which acts like a blanket that traps heat within the atmosphere. Compared to carbon, methane is a particularly potent greenhouse gas.

While carbon is nearly 200 times more prevalent than methane, the latter has contributed to nearly one-third of the observed global warming rate. It has over 80 times the warming power of carbon dioxide in its first 20 years and nearly 30 times its warming power after a 100-year period.

Although improving technologies, such as satellite optical and radar imaging, provide more accurate predictions of methane leakage, the exact magnitude being released into the atmosphere is uncertain. According to the environmental defence fund, in 2012 the United States released up to 60% more methane into the atmosphere than official estimates first suggested.

‘Gas stores are expected to decrease from 95% full in 2022 to 65% full in 2023.’

In a recent analysis, the IEA found that methane emissions from the energy sector are 70% greater than estimates given by the national government. This highlights a dangerous trend in the government of miscalculating the consequences of natural gas usage.

Without accurate predictions, policymakers also run the risk of underestimating the impact of the natural gas sector on the environment and will lack the tools needed to properly plan for the reduction of these emissions.

More than 120 countries have pledged to reduce methane emissions by 30% by 2030 at the UN global climate conference in June of 2022. The Global Methane Energy Pledge Pathway aims to reduce methane emissions by using cost-effective methane mitigation technologies in the oil and gas sector and eliminate routine flaring as soon as possible. Not only is reducing methane necessary, but it is also cheap too.

The IEA estimates that a 75% reduction of methane emissions in the oil and gas sector is possible using technologies that already exist today. Additionally, countries have announced nearly USD $60 million in funding towards reaching these goals.

2016 greenhouse gas emissions by CO2, methane gas and other gases. | Hannah Ritchie and Max Roser / Wikimedia Commons

Despite this pledge, methane emissions have increased by 6% in the past year. If countries are serious about reaching these and other clean air targets, immediate and effective actions need to be taken.

Featured Image: Jay Sterling Austin | Flickr

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