CLIMATE CLIMACTICS AGAIN

I know I have penned several items about climate change but I make no excuse for another on this most critical and alarming phenomenon of our time. On this occasion I am prompted by the latest UN report that exposes just how difficult it will be to meet the targets necessary to bring global warming under control, and by COP 25 in Madrid.

As we know, the general idea, agreed in the latest (2015) Paris Accord, is to bring warming below 1.5°C. It may not seem a lot but it is much harder than it might appear at first sight. The latest UNited Nations Environment Programme (UNEP) data show that we have to reduce emissions of greenhouse gases by 7.6% each year for the next ten years to achieve this goal. Taking the current CO₂ global annual emissions figure of 55.3Gt (Gt is gigatonnes – 1 gigatonne being 1,000,000,000 or 10⁹ tonnes), our global annual CO₂ emissions by 2030 must fall by 32Gt. Even a worst case scenario of maintaining global temperature increases below 2°C would mean an annual reduction of 15Gt!

So far, we have not even managed to move in the right direction, let alone approach the sort of performance that is required despite the remonstrations and extraordinary heft of Greta Thunberg and her young protesters’ army. And she is right – politicians need to stop faffing about and get real. We are likely to lose all our coral reefs, goodness knows how many other marine & terrestrial species (see below) and hit a tipping point of no return that will lead to a dystopian world of storms, inundation from rising sea levels, desertification and famine. Because earth’s systems are interconnected, this could happen much more quickly than we used to think. This is fact-based scientific projection, not hyperbole, whatever some politicians might try to have you believe!

Our seas and oceans are being hit hard by climate change, a major reason why the UN conference COP25 in Madrid, which is happening as I write this, is being called “Blue COP”. The alarming loss of oxygen in our oceans caused by climate change is creating marine “dead zones” where dissolved oxygen is virtually absent, making life impossible for most marine organisms other than some microbes able to survive in an anoxic habitat. Larger fish such as sharks, tuna and marlin are especially vulnerable. Since the 1960s, areas of dangerously depleted marine oxygen have increased dramatically. At least 700 marine areas where oxygen is dangerously low have been identified.

Ocean warming from climate change (warmer water holds less oxygen), pollution from eutrophic agricultural run-off, over-fishing and dumping of plastics are all factors that are leading to marine ecosystem collapse, a truly frightening prospect that will adversely impact the whole earth ecosystem. Oceans are expected to lose around 3% to 4% of their oxygen by the end of this century with the greatest impact in mid & high latitudes and in waters nearest the surface where so much of the marine life is!

COP25 is emphasising how essential the seas and oceans are in the way they protect us from climate turmoil because they soak up such huge amounts of excess atmospheric carbon dioxide and heat. By safeguarding the marine biota, we can improve oceanic ecological function in absorbing CO₂ and helping to mitigate rises in sea level and storm surges. Mangrove communities and coral reefs are an important part of that but both are currently under serious threat..

Marine dead zone illustration. (Reproduced under Creative Commons licence 2.0 Generic (CC BY 2.0),      thank-you.)

The next COP (COP26) will be in Glasgow in 2020. We must make significant progress by then.

I will end with a press release quotation from Dr Monica Verbeek, Executive Director of Seas at Risk who said, “A healthy ocean with abundant wildlife is capable of slowing the rate of climate breakdown substantially. … To date, the most profound impact on the marine environment has come from fishing. Ending overfishing is a quick, deliverable action which will restore fish populations, create more resilient ocean ecosystems, decrease CO₂ pollution and increase carbon capture ...” 

Wake up, people. It will very soon be too late.

© Betts Ecology