Understanding Nord Stream Methane Leaks: Environmental Impacts, Action Plans Identified

The submerged Nord Stream 1 and 2 pipelines, which are located close to Sweden and Denmark, were found to have methane leaks last week. To better understand the phenomenon, a group of combined Earth observation satellites equipped with radar and optical imaging instruments was used.

One of the most hazardous gases for climate change on Earth is methane.

As a result of four ruptures in the underwater Nord Stream 1 and 2 pipelines carrying natural gas beneath the Baltic Sea, it is believed that record amounts of it are currently leaking into the atmosphere.

According to scientists, the Nord Stream leaks are a catastrophe for climate change and the world needs to move quickly to reduce methane emissions.

Methane Gas

According to Australia's New South Wales Environment Protection Authority, methane is an odorless, flammable gas made of carbon and hydrogen. It is one of several greenhouse gases that warm the Earth's atmosphere, causing climate change.

According to the UNEP and Climate and Clean Air Coalition's Global Methane Assessment report, human activity (or anthropogenic) in three sectors is responsible for nearly half of methane emissions worldwide. These include the extraction of fossil fuels, such as oil, gas, and coal, as well as the agriculture sector and the waste industry, which includes landfills and wastewater. Methane is also the known primary element of natural gas.

Pressurized Methane

Even though it partially dissolves in water and is later released as carbon dioxide, methane is not toxic, but it is the second most prevalent anthropogenic greenhouse gas causing climate change in our atmosphere. The size of the gas bubbles grew larger as the pressure decreased as the pressurized gas leaked out of the broken pipe and quickly moved towards the sea surface.

The large gas bubbles above the pipeline rupture had rippled through the sea surface when they reached the surface. From space, there are several ways to detect the presence of gas wafting through the ocean's surface. A few days later, as the gas from the pipelines filled up, it was observed that the estimated radius of the disturbance of methane on the surface of the water had significantly decreased.

Methane Through the Clouds

Synthetic Aperture Radar (SAR) instruments, which are incredibly sensitive to movements in the sea surface on such a scale, are more likely to detect backscatter as a result of the 'roughening' of the sea surface caused by disturbances like these. The first New Space company to take part in the Copernicus Contributing Missions fleet, ICEYE, has instruments on board the Copernicus Sentinel-1 and constellation.

Craig Donlon, Scientist for Ocean and Ice at ESA, said that active microwave radar systems have the advantage over optical systems where they can observe the signatures of bubbling methane through the clouds over a large area and with high spatial resolution, overcoming one of their main drawbacks.

One of the ruptures took place southeast of Bornholm, the Danish Island of Bornholm. But on the evening of September 28, an ICEYE satellite passing over the region captured an image that showed a disruption to the sea surface above the rupture.

Monitoring Methane

GHGSat assigned its high-resolution (approximately 25 m) satellite constellation the task of measuring the Nord Stream 2 gas pipeline leak. While optical satellites can tell us how far the methane bubbles are from the water, they don't tell us much about how much of the gas has been emitted into the atmosphere. Since water absorbs the majority of sunlight in the shortwave infrared wavelengths needed for methane remote sensing, monitoring methane over water is extremely challenging.

The first methane concentration survey made by GHGSat Europe was 79,000 kg per hour, making it the biggest point-source methane leak ever discovered by GHGSat. This rate is incredibly high, especially given that it has been four days since the initial breach and that there are only four places where the Nord Stream pipeline can rupture. Methane concentration readings produced by this pipeline leak were provided by the Copernicus Sentinel-2 satellite.

Environmental Impact

The two Nord Stream stems, which were shut off at the time, had enough gas in them to release 300 000 tonnes of methane, more than twice the amount that California's Aliso Canyon leak for over several months from 2015 to 2016 had released.

Despite its size, the Nord Stream release is nothing compared to the 80 million tonnes of emissions produced annually by the oil and gas sector. The most recent release is comparable to an average day's worth of global methane emissions.

The Sentinel-5P satellite can monitor methane emissions from powerful point sources worldwide in areas with elevated concentrations. A near-infrared spectrometer will be aboard the upcoming atmospheric Copernicus Anthropogenic Carbon Dioxide Monitoring mission (CO2M) to measure atmospheric carbon dioxide as well as methane with high spatial resolution.

Yasjka Meijer, Scientist for Copernicus Atmospheric Missions at ESA, commented that the CO2M Mission will offer worldwide coverage and include a special mode above water to boost observed radiances by aiming toward the sunglint spot, but it will also be constrained by clouds.

Methane as a Pollutant

According to UNEP, methane is a greenhouse gas so "powerful," it has an 80-fold greater potential for global warming than carbon dioxide over 20 years.

Methane has been a contributing factor to global warming for about 30% of human history. The amount of methane in the atmosphere is also increasing at its fastest rate since records have been kept, which dates back to the 1980s.

Natural gas is frequently referred to as a "bridge fuel" to renewable energy by the energy sector since it emits half as much carbon per kilowatt as coal when it is burned.

However, scientists worry that the extent of methane gas leaks from the gas and oil industry may mean that natural gas is more harmful to the climate than coal.

123 oil and gas sites, including those in Hungary, Germany, and Poland, were found to be releasing methane into the atmosphere, according to a recent study by the climate change organization Clean Air Task Force.

World Economic Forum vs. Air Pollution

National ambient air quality standards have been established in more than 50% of countries, but more must be done to safeguard people and the environment. The Clean Air Fund introduced the first global private sector effort to combat air pollution during COP26. The Alliance for Clean Air's founding members is dedicated to tracking and reducing their emissions of air pollution to improve the health of communities everywhere.

Members of the Alliance of Clean Air

Within a year, members of the Alliance for Clean Air hope to establish air pollution footprints for particulate matter, nitrogen oxides, and sulfur oxides. They also seek to identify the locations from which these emissions are coming to monitor human exposure, and they set ambitious goals with a well-defined action plan to reduce air pollution emissions.

The members also serve as advocates for clean air by educating coworkers, clients, and communities about the dangers of air pollution. Additionally, they will support them as they take steps to lessen pollution and assist them in reducing their exposure.

The participants will creatively utilize their resources to speed up clean air solutions.

Read also: The Nord Stream Gas Leaks Raise Climate Concerns, but the Damage Is Difficult to Measure; Germany Suspects Sabotage 

Climate and Clean Air Coalition, Stockholm Environment Institute, and IKEA

The Stockholm Environment Institute, Climate and Clean Air Coalition, and IKEA are introducing a practical framework for businesses on how they can measure air pollution throughout value chains at COP26. The manual will assist businesses in comprehending their effect on air quality and in taking the necessary steps to reduce their emissions.

According to scientists, it is imperative to reduce methane levels immediately to limit global warming to 1.5°C above pre-industrial levels.

Methane begins to decompose after about 10 years, according to the UNEP, whereas carbon dioxide remains in the atmosphere for hundreds to thousands of years. As a result, reducing methane emissions will have a much quicker effect on halting global warming and climate change than reducing CO2 emissions.

What is the world doing about methane?

The Global Methane Pledge, a commitment to reduce methane emissions by 30% by 2030, has been signed by more than 120 nations.

The United States and the EU announced the pledge at the COP26 United Nations Climate Change Summit in Glasgow in 2021.

The Global Methane Pledge Energy Pathway, which hopes to reduce methane emissions generated by the oil and gas sector, is one of its initial initiatives. Speeding up methane mitigation innovations and putting an end to routine flaring are examples of actions. National Public Radio, an American news organization, explains that this is the time when unsold gas is burned.

According to UNEP, adopting a plant-based diet and finding alternate protein sources can aid in lowering methane emissions from agriculture.

The UK imposed a landfill tax in 1996, and the European Commission's Landfill Directive, which set landfilling restrictions in place in 1999, were two of the EU's efforts to cut methane emissions from waste. A joint press release from the EU and the White House on the Global Methane Pledge states that methane emissions from landfills in Europe have nearly decreased by half since 1996, The European Sting reports.

Related article: Why the Nord Stream Methane Leak Can Threaten the Environment