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Inside SALT: Carl Höjman on Filling the Knowledge Gap on Marine Litter

Updated: May 18, 2023

In a conversation with SALT’s acting manager on marine litter, Carl Höjman, he shares his thoughts on the urgency to learn more about marine litter, so that well-informed decisions on prevention and mitigation can be made. Höjman said that “Ogoori is quite unique in its ambitions to create financial value from marine litter found on beaches in Norway, which makes it extra exciting to be part of!”

Portrait photo: Espen Mortensen. Background photo: SALT Lofoten AS.

Ogoori is collaborating with SALT, where they will develop a protocol which ensures that the marine litter gets collected in fractions that best accommodates for the waste treatment that will take place later in the value chain. SALT will collaborate closely with both the collectors of the marine litter as well as with partners on waste management.

Carl Höjman’s biography on SALT reads that he has “accumulated in-depth experience as a consultant in corporate environmental responsibility, climate measures and sustainability reporting.” Whilst also adding “a taste of Sweden's southern coast to the SALT crew.”

SALT is focused on advisory and research services related to the marine environment and coastal communities. They have a thorough track record of knowledge creation around marine litter, particularly macroplastics, in a Norwegian and Arctic setting.

Dead Giant Sea Turtles on Adam’s Bridge

In 2017, Carl Höjman and his partner travelled to Sri Lanka to work on their desktop whilst also volunteering as sustainability advisors for Kitesurfing Lanka for half a year. They had already a relationship to Sri Lanka after several visits for studying, working and leisure.

What they witnessed there was the “staggering” abundance of marine litter that was “right in their faces”. They were disturbed and deeply worried about the general public’s rapidly increasing use and littering of plastic packaging in combination with a dysfunctional and outdated waste management system.

“We got involved with arranging clean-up actions together with the many like-minded tourists. Also, we got to know this guy Dilsiri from Kitesurfing Lanka, a very environmentally conscious entrepreneur, running one of the biggest kite surfing resorts in Sri Lanka.”

The kitesurf resort is located right at the foot of the legendary sand bar “Adam’s Bridge”, that has connected India and Sri Lanka in recent geological time.

“The gigantic sand bridge was just covered with litter. As I was jogging along the shores, I counted 17 giant sea turtles lying in the sand - dead. And on a 7 km stretch. I came to the point where I was returning, and I just stood there screaming out in the air. I was really frustrated. Why was there so much litter in this remote and special nature reserve? Where did it come from, and for what causes? The whole situation of mass death, natural paradise turned to wasteland, and lack of knowledge, really got me worried.”

Photo: SALT Lofoten AS.

Marine Litter Knowledge Gaps

Höjman was already engaged in environmental issues since 2006, the time when he was studying environmental science at Lund University; and bearing witness to the dead sea turtles, he felt the sheer urgency to tackle the issue of marine littering, as it is closely linked with “so many other important societal and environmental issues, such as loss of biodiversity, water and sanitation, jobs and circular economy, etc.”

“We need to build a better understanding about marine litter. This is what SALT is doing, and we work closely together with clean-up organisations, fisheries industry and others to gain insights on how much, where, what and why there is marine litter. Is the litter new or old, and hence is the littering still going on? Our insights can feed into decision-making on many levels.”

SALT has already collected large data sets along the coasts of East Agder region, Lofoten, Vesterålen and parts of Finnmark. And a range of new areas will be covered in the year to come.

“Without robust and reliable information, we will not be able to make well-informed decisions on prevention and mitigation. SALT aims to fill in as many of these knowledge gaps as possible!”

Better Monitoring of Marine Litter

SALT wants to contribute to establishing new protocols that can be used for monitoring marine litter nationally, and maybe even internationally, which can feed into policy work. Höjman explained that the authorities are on the hunt for such methods and protocols. As with other important environmental issues, marine litter deserves well-established and efficient monitoring and management programs. This is now clearly in the making.

Photo: SALT Lofoten AS.

“So a lot of attention and resources has gone into encouraging voluntary clean-up actions, which is great. But we need to widen the attention to professionalize, expand and make efforts more efficient.”

SALT Research Says Cleanup Has Local Impact

SALT has recently published a scientific paper based on public beach cleaning data, showing that the amount of marine litter has gone down in Lofoten in the period from 2011 to 2018. They analysed volunteer cleanup data, such as total weight and counts of select litter types, from over 200 locations. They revealed a decline in 25 kg stranded marine litter per 100 metre beach-stretch from the beginning to the end of the period.

“The reason for the decline was not possible to uncover, but is likely a combination of clean-up actions and decreased input of litter to the environment,” says Höjman.

Where to Focus Efforts on Marine Litter

“Many million tonnes of litter enter the ocean every year, a number that is rapidly increasing. If anything, we should focus on preventing that from happening in the first case. But, the damage is already done, and we cannot let the litter out there just lay around for centuries and accumulate. We also need to focus efforts on efficiently picking it up and bring it back to be treated as waste should be. But where to best focus our clean-up efforts?”

Höjman argues that getting as close to the source as possible is true for riverine plastics that have not yet entered the oceans. But after getting out on the open sea, things get difficult.

“Oceans are huge, and even at the centre of the litter accumulating gyre of the ‘Great Pacific Garbage Patch’, only 100 kilograms of litter per square kilometre has been recorded according to the best available science. That’s a very sparse soup in a very remote and large area. However, coastlines show much higher concentrations of litter, whilst being more accessible and removable.”

The team at SALT is currently reviewing all available scientific literature on macro litter, to result in a peer review paper summarizing current scientific knowledge. The review will be published this coming fall and can possibly help the global community to gain a better perspective on the distribution of macro litter in river systems, the ocean and along shores.

Read more about their work:

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