Reports

The effects of the Icelandic demersal trawling fleet renewal on product carbon footprint / Áhrif endurnýjunar fiskiskipaflotans á kolefnisspor afurða

Published:

27/05/2025

Authors:

Guðrún Svana Hilmarsdóttir, Jónas R. Viðarsson, Birgir Örn Smárason, Sæmundur Elíasson, Ólafur Ögmundarson

Supported by:

The AVS fund, the Icelandic Food Innovation Fund / Matvælasjóður and the Research fund of the University of Iceland

Contact

Jónas Rúnar Viðarsson

Sviðsstjóri rannsókna

jonas@matis.is

This report presents the background, implementation, results and discussions connected to a peer-reviewed scientific journal article published in the Journal of Cleaner Production in November 2024. Scientific journals have strict requirements regarding the length of articles, and therefore it was not possible to present all the details that the authors would have liked in the paper. This report therefore provides additional information that was not included in.
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There has been a major renewal of the Icelandic trawler fleet since the turn of the century, while the number of such vessels has decreased by almost half. It has been claimed that the new vessels are much more fuel-efficient and that the carbon footprint of the products must therefore have decreased as results. Data on oil imports to fishing vessels seem to support these claims.

To better analyse the impacts of the fleet renewal on the carbon footprint of fish catches, several representatives from the Icelandic bottom trawler sector joined forces with experts from Matís, the University of Iceland and the University of Akureyri that work on assessing the environmental impacts in production systems. Data was collected from 11 trawlers over a 10-year period and a Life Cycle Assessment (LCA) methodology was applied to analyse their carbon footprint per unit of catch, and then a comparison was made between older and newer vessels to examine if there is a statistically significant difference. The vessels in the sample were chosen to provide a good cross-section of the Icelandic bottom-trawl fleet in terms of size, age, catch composition and location around the country. The sample included four new vessels that were purchased to replace older vessels, i.e. a comparison was made between old and newer vessels from the same fishing company, with the same catch quotas and even the same crew.

The results of the analysis revealed that the renewal of the trawl fleet alone has not had a significant impact on the carbon footprint per unit of catch. Three of the four new vessels examined did not show lower carbon footprint than the older vessels they replaced. The fourth vessel, however, showed a significant reduction in the carbon footprint, but that may be because it replaced two older vessels. The most likely explanation is therefore that since the catch quotas of two vessels were combined on one new vessel, it is the quota status and fishing pattern that had the dominant effect, rather than the age of the vessels. These results consistent with previous studies in Iceland, which have shown that the state of fish stocks, catch quotas, and fishing patterns are by far the most important factors when it comes to greenhouse gas emissions per unit of catch. Thus, the concentration of catch quotas and the reduction in the number of vessels have had a decisive effect on reducing the carbon footprint, rather than fleet renewal. However, it is worth bearing in mind that comparisons between years can be difficult as stock abundance and distribution, as well as catch patterns can vary greatly from year to year.

The results of the life cycle analysis also provided information on the average carbon footprint per unit of catch for the vessels in the sample. This is very important information, as such a comprehensive analysis of the carbon footprint of bottom-trawl catches has not been carried out in Iceland before. Previous data only covered individual trawlers over much shorter periods. The results show that the carbon footprint of a landed cod catch is 0.7 kg CO2 equivalent/kg catch, 0.8 kg when the carbon footprint is allocated to the edible part of the catch, and 4.5 kg when it is allocated to protein content of the edible parts. Similar results were shown for haddock and saithe, but the carbon footprint of redfish is much higher as the fishing itself is more energy-intensive and the utilisation for human consumption is much lower. These results are similar to comparable studies that have been conducted in recent years in the countries the Icelandic seafood industry prefers to compare with. When these values are compared to other protein sources, it is clear that Icelandic bottom-trawl catches are among the protein sources in the world with the lowest carbon footprint. For example, poultry has more than 12 times the carbon footprint per protein unit than the Icelandic cod, pork has 17 times the footprint, and beef has 80 times the footprint. It should be noted, however, that these are global averages.

It should be noted that the life cycle analysis only covered the fishing part of the value chain and that it did not take into account the effects that have been shown in previous studies to have a negligible effect on the carbon footprint of trawling. It also did not take into account the effects of trawling on the seabed, although in recent years it has been suggested that trawling releases large amounts of CO2 that is captured in bottom sediments. However, the scientific community has not agreed on what these effects actually are. The analysis was carried out in accordance with international standards, ISO 14044, and the results are therefore fully comparable with other studies where the same standards have been followed.

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Peer-reviewed articles

Greenhouse gas emissions of environmentally sustainable diets: Insights from the Icelandic National Dietary Survey 2019–2021

Abstract

Background

Health authorities are increasingly integrating environmental sustainability considerations into food-based dietary guidelines. However, concerns persist about the accuracy of the data used to assess environmental impacts, as well as the extent to which these guidelines are followed in practice.

Aim

To compare dietary greenhouse gas (GHG) emissions estimates using different top-down and bottom-up life cycle assessment (LCA) databases; and to estimate GHG emissions of food consumption within the ranges set for meat and dairy in recently proposed environmentally sustainable diets.

Methods

Dietary GHG emissions were estimated for participants in the 2019–2021 Icelandic National Dietary Survey (n = 822) using three publicly available LCA databases from Denmark, the US, and France. GHG emissions among participants whose consumption was aligned with the EAT-Lancet diet, the 2021 Danish food-based dietary guidelines and the 2023 Nordic Nutrition Recommendations were also quantified.

Results

The mean dietary GHG emissions among participants were 6.3, 6.1, and 6.1 kg CO2-eq/day based on the Danish (top-down), US (bottom-up), and French (bottom-up) databases, respectively. The relative ranking of foods was also consistent across all three databases. For example, the relative contribution of total CO2-eq (% range for the three databases) was highest for red meat (39–51%), followed by dairy (10–17%) and beverages (9–13%). The contribution from plant-based foods (6–10%), seafood (4–11%), and poultry/eggs (<5%) was modest. The dietary habits of most participants (86%) were outside the ranges for meat and dairy consumption as set by the three sustainable diets. However, participants reporting consumption within the ranges for meat and dairy had mean GHG emissions ranging between 4.2 and 4.7 kg CO2-eq/day, depending on the diet. In comparison, the mean for participants not adhering to the sustainable diets was 7.7 kg CO2-eq/day. These results are higher than those reported in other Nordic and European studies, likely due to high consumption of lamb, beef, and dairy, and low consumption of plant-based food.

Conclusion

All three LCA databases provided similar estimates for total dietary GHG emissions and relative ranking of different food groups. Based on current dietary habits in Iceland, adherence to environmentally sustainable diets would lead to a substantial reduction in dietary GHG emissions.

Reports

Life Cycle Assessment on fresh Icelandic cod loins

Published:

01/09/2014

Authors:

Birgir Örn Smárason, Jónas R. Viðarsson, Gunnar Þórðarson, Lilja Magnúsdóttir

Supported by:

AVS (R13 042‐13)

Contact

Birgir Örn Smárason

Research Group Leader

birgir@matis.is

Life Cycle Assessment on fresh Icelandic cod loins

With growing human population and increased fish consumption, the world's fisheries are not only facing the challenge of harvesting fish stocks in a sustainable manner, but also to limit the environmental impacts along the entire value chain. The fishing industry, like all other industries, contributes to global warming and other environmental impacts with consequent marine ecosystem deterioration. Environmentally responsible producers, distributors, retailers and consumers recognize this and are actively engaged in mapping the environmental impacts of their products and constantly looking for ways to limit the effects. In this project a group of Icelandic researchers and suppliers of fresh Icelandic cod loins carried out Life Cycle Assessment (LCA) within selected value chains. The results were compared with similar research on competing products and potentials for improvements identified. The project included LCA of fresh cod loins sold in the UK and Switzerland from three bottom trawlers and four long‐ liners. The results show that fishing gear has considerable impact on carbon footprint values with numbers ranging from 0.3 to 1.1 kg CO2eq / kg product. The catching phase impacts is however dominated by the transport phase, where transport by air contributes to over 60% of the total CO2 emissions within the chain. Interestingly, transport by sea to the UK emits even less CO2 than domestic transport. Minimizing the carbon footprint, and environmental impacts in general, associated with the provision of seafood can make a potentially important contribution to climate change control. Favoring low impact fishing gear and transportation can lead to reduction in CO2 emissions, but that is not always practical or even applicable due to the limited availability of sea freight alternatives, time constrains, quality issues and other factors. When comparing the results with other similar results for competing products it is evident that fresh Icelandic cod loins have moderate CO2 emissions.

Along with high population growth and increased fish consumption, the global fisheries sector now faces the important task of utilizing fish stocks sustainably at the same time as they need to minimize all the environmental impact of fishing, processing, transport and other links in the value chain. The fishing industry, like any other industry, contributes to global warming and also has a number of other environmental impacts that have a detrimental effect on the marine environment. Companies that want to show social and environmental responsibility in their operations are fully aware of this and therefore seek to better monitor the environmental impact of their production and look for ways to reduce it. With this in mind, a group of Icelandic researchers, fisheries companies and sales and distributors joined forces to carry out an LCA analysis of selected value chains of fresh cod necks. The results were then compared with the results of comparable studies that have been conducted on competitive products, as well as ways to reduce the environmental impact within the aforementioned value chains were examined. The study included fresh Icelandic cod necks sold in the UK and Switzerland. The saddles were made from the catch of three trawlers and four longliners. The results show that the type of fishing gear has a great influence on the footprint / carbon footprint of the products, as the longliners came out considerably better than the trawlers. The footprint of individual vessels in the study ranged from 0.3 to 1.1 kg CO2eq / kg product, which must be considered quite low compared to previous studies. When it comes to looking at the entire value chain, however, it is the transport component or mode of transport that is by far the most important, i.e. that part is responsible for over 60% of the footprint when the product is exported by air. If, on the other hand, it is exported by ship, the footprint of the transport part will be very small and then domestic transport will become more important than the transport across the sea. Minimizing the environmental impact of fishing, processing and distributing marine products can make a significant contribution to the fight against global warming. By choosing fishing methods and modes of transport with regard to the footprint, it is possible to significantly reduce carbon emissions, but it must also be borne in mind that it is not always possible or realistic to choose only the options with the lowest footprint. The results of this study and a comparison with the results of comparable studies show that fresh Icelandic cod fillets that have been marketed in the UK and Switzerland have a modest footprint and are fully competitive with other fish products or animal proteins.

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Reports

Comparison of transport modes and packaging methods for fresh fish products - storage life study and life cycle assessment

Published:

01/10/2012

Authors:

Björn Margeirsson, Birgir Örn Smárason, Gunnar Þórðarson, Aðalheiður Ólafsdóttir, Eyjólfur Reynisson, Óðinn Gestsson, Emilía Martinsdóttir, Sigurjón Arason

Supported by:

AtVest (Atvinnuþróunarfélag Vestfjarði)

Contact

Birgir Örn Smárason

Research Group Leader

birgir@matis.is

Comparison of transport modes and packaging methods for fresh fish products - storage life study and life cycle assessment

There is a great benefit in improved control of the value chain of exports of fresh fish knuckles for distribution in retail chains in the UK. Improved packaging methods could increase the shelf life of a product, which is fundamental to this business. With an airtight container, it would be possible to transport the product in a sludge tank with a low temperature (down to -1 ° C), which would both reduce the transport cost significantly and could also extend the shelf life of the product. The method also provides the option of packaging with consumer information, which makes further packaging abroad unnecessary. In air transport, it would be possible to pack all goods in a 12 kg foam box instead of 3 kg, as is most common today, thus saving significant transport costs. Temperature measurements, sensory evaluation, chemical and microbial measurements and life cycle analysis were used to compare different packaging solutions for sea and air transport. Fresh haddock pieces in vacuum-packed containers in a container with slush ice, which were stored at a typical temperature in container transport, turned out to have a shelf life of 3-4 days longer than the other experimental groups, probably mainly due to better temperature control. Consistency between the results of sensory evaluation and microbiological measurements was generally good. The lowest environmental impact of all groups was the pot group with sea-transported, vacuum-packed packaging, but this design could be further improved with regard to the mixing of the ice scraper and fish temperature control and thus the shelf life.

The aim of the project was to compare alternative packaging methods of fresh fish loins to the traditional packaging. Comparison was made between packages in terms of temperature control and product storage life by simulating air and sea transport from Iceland to UK in air climate chambers. The evaluation was made by the sensory panel and microbialand chemical analysis by the Matís laboratory in Reykjavík. Furthermore, the environmental impact of the aforementioned transport modes and packaging methods was assessed by means of LCA (Life Cycle Assessment). About 70–75% of Iceland's exports of fresh fillets and loins are transported by air and the rest by container ships. Increased knowledge on the advantages and disadvantages of the packages used for this fresh fish export will facilitate the selection of packages and improve the quality and storage life of the products. By using vacuum-packaging it is possible to use 12 kg packages in air freight instead of the traditional 3– 5 kg packages; but the market is increasingly demanding smaller individual packages. Sea transported larger packages use less space in shipping, lowering freight cost and environmental impact. Vacuum packed haddock loins immersed in slurry ice in a fish tub stored at sea transport temperature conditions proved to have a 3–4 day longer storage life than all the other experimental groups, probably mainly because of better temperature control. Good agreement was obtained between the sensory- and microbial evaluation. Finally, the sea transport-tub-group was found to be the most environmentally friendly and could be improved with regard to product temperature control and thereby storage life.

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EN