Marine Environments May Bear The Greatest Negative Effects Of Climate Change

sharks in the marine environment

Planning is necessary to promote the sustainable development of marine environments, just as there has long been spatial planning for activities on land.

Researchers from the University of Gothenburg and other institutions have now demonstrated that marine planning must now take climate change into account, which it does not currently. According to the researchers’ models, temperature and salt content changes may affect ecosystems and species more than all other environmental factors combined.

Since a few years ago, Symphony has been a digital tool for ecosystem-based marine spatial planning. It makes use of GIS maps to illustrate how significant ecosystems and species are distributed along Sweden’s coastlines and how environmental disturbances like nutrient pollution, boat traffic, and fishing affect them in various regions.

The maps are used to direct public authorities and other parties involved in marine planning when setting priorities and implementing various measures.

Adjusting For Temperature Changes

The current iteration of Symphony has the drawback of not taking future climate change into account. Researchers working on the ClimeMarine project have now examined what occurs when the tool is adjusted to account for anticipated changes in temperature and salt content.

“It showed that the anticipated climate changes will increase the total environmental impact by at least fifty percent, and in some areas, as much as several hundred percent,”

said co-author Per Jonsson, researcher at the University of Gothenburg.

The GIS maps demonstrate how the impacts of climate change differ for various regions.

“It’s a clear sign that we may need to reduce other impacts to lower the total rate of impact in some areas. For example, in areas with valuable eelgrass meadows, we might consider rerouting a shipping line or slowing the expansion of marinas and leisure boating,”

said Jonsson.

Reaction Of Ecosystems and Species

mpact maps for the Kattegat-Skagerrak, Baltic Proper, and the Gulf of Bothnia showing the percentage change between the baseline and the MEDIAN model ensemble
Impact maps for the analyzed area. Impact maps for the Kattegat-Skagerrak, Baltic Proper, and the Gulf of Bothnia showing the percentage change between the baseline and the MEDIAN model ensemble for RCP4.5 (a) and RCP8.5 (b). Embedded text boxes denote change of cumulative impact per area (over the calculated anthropogenic environmental impact from human activities), including values for MINIMUM, MEDIAN, and MAXIMUM model ensembles. The impact maps are based on the geographical distribution of ecosystem components and pressures, plus the sensitivity scores. The small map shows the Northern Europe and approximately the three analyzed areas covering the Swedish territorial water and EEZ. Note, the three different areas have been analyzed separately and are not directly comparable. Credit: Global Change Biology (2022). DOI: 10.1111/gcb.16312

The tool also makes it possible to pinpoint regions that are predicted to be less affected by climate change, such as so-called upwelling regions like those off the coast of Gotland, where deep, cold water rises and cools the water at the surface. These places can serve as climate refuges, allowing vulnerable species to survive.

“Marine reserves may be considered to protect these areas, where we ‘remove’ other factors that have an impact. Sweden has committed to establishing several new protected marine areas, and Symphony can help identify where they should be located.”

These forecasts naturally have flaws, as Per Jonsson points out. The mathematical models that are used to predict future temperatures and salt content are being developed and improved on all the time.

Additionally, we are unsure of what will transpire with our carbon dioxide emissions in the future. Political issues are challenging to evaluate.

“We also need to better understand how sensitive different ecosystems and species are to climate change. We need experimental studies that show what happens when the temperature rises and salt content decreases.”

He is certain that climate change will have an impact on marine environments in the future even without these, though.

Reference: Iréne Wåhlström et al, Projected climate change impact on a coastal sea—As significant as all current pressures combined, Global Change Biology (2022). DOI: 10.1111/gcb.16312