… It is, according to this story in Carbon Brief.
Never mind what BP did to the Gulf, never mind the Exxon Valdez. Never mind over-fishing, pollution, de-oxygenated blooms at the mouths of rivers worldwide.
The Carbon Brief story references a paper just published in Nature Communications titled “Spatial and temporal changes in cumulative human impacts on the world’s ocean.”
The paper says “Globally, increases in climate change stressors (sea surface temperature anomalies, ocean acidification and ultraviolet radiation) drove most of the increase in cumulative impact, confirming the need to address climate change to maintain and sustain marine ecosystems globally.”
However, they also write “Nearly 66% of the ocean experienced increases in cumulative impact over the 5-year study span Increases tended to be located in tropical, subtropical and coastal regions, with average increases in 77% of all exclusive economic zones.” That would suggest that other human contributions might be more significant.
And in fact, according to the paper, “Overall, countries with greater increases in coastal population had larger 5-year changes in cumulative impacts.”
Well, okay–they suckered me in. Let’s look at sea surface temperatures, which, according to the European Environmental Agency are 1 degree Celsius higher than they were 140 years ago.
Here is how they describe the impacts:
“Some organisms are now appearing earlier in their seasonal cycles than in the past.”
“The consequences include increased vulnerability of North Sea cod and stocks to over-fishing”
“Fish and plankton have expanded their geographical distribution further north in response to increasing temperatures. Depending on the species this expansion occurs at an average rate of 30 -100 km per year.”
My problem with the paper is that they lump together various potential impacts–sea surface temperatures, acidification and UV radiation–and assign it a score that is hard to disambiguate. The only impacts I have seen discussed with regards to acidification are to coral reefs, and it appears that impacts are being re-evaluated as the reefs show surprising resilience–as soon as other human impacts, such as dynamite fishing, are removed from the picture.
I have seen no discussion of the impacts of UV radiation. Perhaps a better-informed reader will guide me.
The upshot appears to be that 1C of warming sea surface temperatures have changed seasonal movement and growth patterns in some species, very similar to what has happened on land.
Until there is greater visibility on how their metrics are defined I will remain of the opinion that climate change has had far less impact on our oceans than pollution, over-fishing and introduction of alien species. Just as it has been on land.