Can I blame the miserable spring on a slowing Gulf Stream?
The chat around the office kettle is again about how long this winter has felt. It's practically May. Apart from a week when temperatures were heading towards 30 degrees, it feels like we've been cold and wet for months. The cyclists among us have been soaked through more often than we can remember. The sky, for the most part, is the colour of a steel bucket. Today in London it's 6 degrees.
We’re not alone. Farmers in the north of England have reported lambs dying and crops failing in waterlogged fields. Some say it’s their worst spring for 25 years. March brought the Beast from the East. Dog owners have been warned about Alabama foot rot being spread by the unusually muddy state of parks. Bird-watchers claim chiffchaffs – which some say mark the true arrival of spring – broke into song 20 days later than in 2017.
And then there’s the big scary news that the Gulf Stream is slowing down. So that explains the never-ending winter, right? Well…
What has the Gulf Stream ever done for us?
As we know, the Gulf Stream keeps the UK warmer than it would otherwise be.
This colossal oceanic system known as the Atlantic Meridional Overturning Circulation bears warm water from the equatorial region of the Atlantic for thousands of miles, via the Gulf of Mexico, towards the North Pole. On the way it kisses the British Isles before heading further north where it cools, sinks and returns southward.
As a result of that warm visit, our winters are relatively mild compared to countries on a similar latitude.
Think of Canada's major cities and you perhaps think of snow – Quebec, Toronto, Montreal, Vancouver: yet all are further south than London. London is also north of all of Japan, most of China, and the majority of Mongolia. Then there’s New York City, which gets on average 2 foot of snow a year. We have the Gulf Stream, they get the snow.
Thanks in part to the Gulf Stream, the west coast of Scotland is rich in wild flowers even in winter. The Isle of Arran has up to 50 species of wild flowers in the winter, the most common being gorse. Its flowering season starts in November and peaks in late spring.
In fact, the Gulf Stream keeps the UK around 5 degrees centigrade warmer than it would otherwise be. Without it the UK could see average winter temperatures (December-February) around freezing. Much of the precipitation during this period would fall as snow.
The UK famously almost grinds to a standstill after a flurry of snow. So it’s hard to imagine us coping with freezing temperatures for months on end. And even if we could, much of our native wildlife probably couldn’t.
What's happening to the Gulf Stream?
But is that where we’re heading? Is the Gulf Stream slowing down? And is it to blame for the miserable so-called spring we’ve had this year?
As far as scientists can tell – we haven’t been monitoring it for thousands of years – the Gulf Stream really is slowing down.
Two papers were recently published in the prestigious academic journal 'Nature'. Basically, both said that a warmer planet slows the Gulf Stream. Global warming lessens the cooling of the water in the current, and melting ice is adding fresh water at the northern end of the system; fresh water is less dense than salt water, and this is weakening the current.
One of the papers in 'Nature' said the Gulf Stream had slowed by around 15% mostly as a result of man-made climate change. The other said that the slowdown began with the end of the last mini-ice age (around the middle of the 19th century), which was caused by the sun going through a weaker period of activity.
It seems clear that the Gulf Stream is not going to collapse as abruptly as it did in the sci-fi thriller The Day after Tomorrow. But a weakening Gulf Stream is likely to, and perhaps already could be, disrupting weather patterns says Levke Ceaser, lead author of one of the papers.
Which does imply that allowing global warming to go unchecked could continue to affect the strength of the Gulf Stream, which in turn could affect weather patterns.
But it would be a brave or foolish scientist who would speculate that the miserable spring we’ve been having is due to the slow-down in the Gulf Stream.
We just don’t yet know enough about the implications of a slower Gulf Stream. And anyway weather patterns show significant variability.
The line from the Met Office on our bad winter is anything but dramatic. December to February “generally was rather unsettled” it says. Admittedly the mean temperature for the period was a tad lower than the 1981-2010 average. But – get this - rainfall in those 3 months was also slightly lower and, we actually had more hours of sunshine than the average for the period. We’ll have to wait a while to see officially how bad or good spring has been.
We need to curb climate change
So don’t rush to blame climate change or a weakening Gulf Stream for this apparently wet and cold spring.
Right now there is something tangible to focus on. We already know with a high degree of certainty that by warming the planet we’re playing a deadly serious game of roulette with the lives of future generations.
The best way to call time on this game is to ensure we leave oil, gas and coal in the ground. Stop drilling for oil, skip fracking and switch to renewables.
Please support Friends of the Earth’s efforts to limit climate change and protect generations to come and our wonderful wildlife.