When one plunges into the ocean off Mayo, the extreme marine heatwave being experienced in the North Atlantic is not immediately obvious. To a fair-weather swimmer like me at least, the shock of the icy water is still intense.
It can be hard to believe that Ireland is experiencing one of the most extreme marine heatwaves on earth. The data is stark and even more difficult to fathom. An “unheard of” marine heatwave – defined as a period of persistent anomalously warm ocean temperatures, which can disrupt ecosystems – off the coast of Ireland and the UK has raised sea temperatures by four to five degrees.
The marine heatwave in our North Atlantic waters is classified as “extreme” by the US National Oceanic and Atmospheric Administration (NOAA), which is predicting – based on experimental forecasts – that half of the world’s oceans may experience marine heatwave conditions by September. In April, May and June, global sea temperatures already reached all-time highs.
A five-degree anomaly doesn’t sound too bad, surely?
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In Ireland, which has so far avoided the large death tolls experienced in other parts of Europe in recent years, heatwaves are sometimes glibly greeted as good news, evoking images of 99s and days on the beach.
Apart from a more enjoyable swimming experience, the scale and implications of this heatwave are nearly impossible for us to conceive. Met Éireann reports that, in June, Ireland experienced a “category-four heatwave in parts of the North Atlantic off the coast of Ireland … with some hotspots hitting category five … conditions which are ‘beyond extreme’.” It warns that both the intensity and frequency of marine heatwaves will increase for the next few decades. Yet this is garnering relatively limited media coverage, and notably lacking the political haymaking and public outrage that accompanies any other risk to the Irish fishing industry.
This ocean heatwave is a brewing disaster for the fishing industry in Ireland, both in the short and long term, as Pacific marine heatwaves have shown. The NOAA warns of “mass die-offs of fish, marine mammals and seabirds, [the potential to] disrupt food webs and fisheries, bleach corals, spur harmful algal blooms and wipe out seaweeds. Billions of dollars are lost in such events around the world each year.”
Marine heatwaves pose a greater threat to Irish fishing than any Brexit quota row ever was. Warming seas drive fish in search of cooler waters, disrupt reproduction cycles, cause mass deaths and kill off kelp forests which are valuable nurseries to all manner of life. Smaller boats will be the first to feel these effects as fish move into deeper waters and historical breeding grounds are abandoned. In the medium term, this means fewer jobs in coastal communities; in the longer term, a loss of identity for entire communities.
Island communities
Marine heatwaves also mean more extreme coastal storms which, for anybody who has ever experienced waves battering their house or heard the unholy roar of a storm engulfing a coastal town or village, is a terrifying prospect. Politicians arrive the following morning and walk around looking at the debris from a storm, but taking action now to prevent increasingly extreme storms is not a political priority. With sea levels rising more rapidly and more severe storms a certainty, the fate of many coastal areas is already sealed. Even now, insurers are refusing to cover homes in some areas for flooding.
In island communities such as Achill, where I live, the ocean has a hand in shaping everything from where houses are built to what sort of farming is practised and how people earn money. Places such as Achill have developed over decades with a fairly steady and predictable ocean system. We are entirely unprepared for the changes that are happening now. It is not an exaggeration to say that homes will be destroyed and entire coastal economies based on fishing and tourism will suffer. The homes and livelihoods I am talking about are those belonging to my family, my neighbours and the people I grew up with. The lack of political urgency around the collapse of our ocean systems is a clear political message to communities such as Achill that our future is not worth fighting for.
[ The sea is unusually warm off Irish coasts. We should be worriedOpens in new window ]
People will move away, jobs will be lost, schools will close, piers and roads will fall into disrepair, entire communities that go back generations will become entirely seasonal or will be broken up and dispersed.
Various factors, including less dust from the Sahara and El Nino conditions, have been blamed, but the real cause of this marine heatwave is the oil and gas industry. Yes, there have always been anomalies in weather but we cannot now speak about extreme record-breaking weather events without talking about climate change. As the regular comparison goes, talking about extreme weather events without mentioning climate change is like talking about an athlete who wins gold without mentioning they’re on steroids.
Climate collapse can sometimes feel like it’s something that cannot be stopped, but at every stage there is a person making decisions that affect us all. The executives of oil and gas companies have known for decades that emissions from fossil fuels are causing the earth to heat up, and still they are expanding operations, drilling more, polluting more and earning eye-watering sums.
Unlike the issue of quotas, the necessary short-term response to marine heatwaves is to reduce fishing to give marine life a chance at survival. Fishing is not responsible for the heatwave, but a halt on fishing would give respite to fish trying to deal simultaneously with extreme heat stress, pollution and death by fishing net.
More long term, the obvious answer is the development of proper marine protected areas where no destructive human activity takes place, alongside the well overdue phasing out of greenhouse gas emissions. Marine protected areas act as safe havens for sea life, allowing fish and shellfish to grow larger and produce more offspring, which has knock-on positive effects for the ocean surrounding the protected area. This in turn has been shown to improve the number and size of fish caught in surrounding fisheries.
Currently 8.3 per cent of Ireland’s waters are designated as protected – but functionally none of them is. Beyond what they are worth to the fishing industry, fish, marine life and the oceans have intrinsic value in and of themselves.
We need to step back and give the oceans a break and the chance to recover from the extreme heat that has been caused by emissions arising mainly from oil and gas. If we don’t take action, then we are all like fish in slowly boiling waters.
Saoirse McHugh is an environmental activist from Achill Island