Why does a bit of snow bring Britain to a standstill?

Not gonna lie, only included this because it was my local station growing up. Image: Getty.

A couple of times a year, the UK is presented with the competing emotions of seeing children bouncing off the walls with excitement and the dread of the chaotic morning commute. It is snowing.

You might hear British people asking: “Why are we so bad at dealing with snow? Why can’t we just keep the child-like thrill of it without suffering the delayed flights, broken coccyx and battered bodywork? Why can’t we be like other countries and just take it in our stride? ”

There’s not actually a simple answer to this. The reality is that investing in the infrastructure and equipment to make it easier to cope with snow – heated runways, fancier snow ploughs and the rest – would be extremely expensive.

There is a cost-benefit analysis that would tell you how much the annual chaos of a day of snow costs compared with the investment needed to avoid it and the benefits of that. The UK Met Office, government and councils do exactly that, working out what level of investment is appropriate to mitigate occasional chaos.

In fact, because snow is relatively rare for the UK, it is possible that much of the chaos arises from not being well-practised in driving or walking in slippery conditions – and no amount of spending is going to cure that.

Every British driver could go and buy winter tyres for their cars. But this illustrates that the solutions developed for other countries do not necessarily translate directly to UK conditions. The British climate is benign: wet and relatively warm.

Winter tyres used in Sweden, Canada or the Switzerland will be optimised for much colder conditions – made from softer rubber to maintain grip well below freezing. This would just wear very quickly on typical UK winter days, which are not really very cold at all by comparison.


Unlike places well-versed in coping with snow, the UK rarely has extended of periods of cold with snow that freeze the ground so that the snow stays around. When snow falls, it usually lands on warmer ground and at least some of the snow melts straight away.

This combination of a little snow mixed with water creates the slushy conditions that really are very slippery. If the climate was colder then then snow would settle as drier snow and it would be much crunchier and grippier underfoot.

Yet when this powdery kind of snow does occur, it can cause just as much havoc as authorities are less used to dealing with it. This problem has led to the now famous excuse that Britain’s trains can quickly be brought to a standstill by the “wrong kind of snow”. This illustrates that no two snow showers are the same, and the closer to melting point the temperature is, the more variable and tricky the snow can be.

So while it might seem like Britain is ground to a halt by less extreme weather than other countries can deal with, in some ways the milder climate is actually harder to deal with. The Conversation

Barbara Turnbull is an associate professor in environmental fluid mechanics at the University of Nottingham.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

The IPPC report on the melting ice caps makes for terrifying reading

A Greeland iceberg, 2007. Image: Getty.

Earlier this year, the Intergovernmental Panel on Climate Change (IPCC) – the UN body responsible for communicating the science of climate breakdown – released its long-awaited Special Report on the Ocean and Cryosphere in a Changing Climate.

Based on almost 7,000 peer-reviewed research articles, the report is a cutting-edge crash course in how human-caused climate breakdown is changing our ice and oceans and what it means for humanity and the living planet. In a nutshell, the news isn’t good.

Cryosphere in decline

Most of us rarely come into contact with the cryosphere, but it is a critical part of our climate system. The term refers to the frozen parts of our planet – the great ice sheets of Greenland and Antarctica, the icebergs that break off and drift in the oceans, the glaciers on our high mountain ranges, our winter snow, the ice on lakes and the polar oceans, and the frozen ground in much of the Arctic landscape called permafrost.

The cryosphere is shrinking. Snow cover is reducing, glaciers and ice sheets are melting and permafrost is thawing. We’ve known this for most of my 25-year career, but the report highlights that melting is accelerating, with potentially disastrous consequences for humanity and marine and high mountain ecosystems.

At the moment, we’re on track to lose more than half of all the permafrost by the end of the century. Thousands of roads and buildings sit on this frozen soil – and their foundations are slowly transitioning to mud. Permafrost also stores almost twice the amount of carbon as is present in the atmosphere. While increased plant growth may be able to offset some of the release of carbon from newly thawed soils, much will be released to the atmosphere, significantly accelerating the pace of global heating.

Sea ice is declining rapidly, and an ice-free Arctic ocean will become a regular summer occurrence as things stand. Indigenous peoples who live in the Arctic are already having to change how they hunt and travel, and some coastal communities are already planning for relocation. Populations of seals, walruses, polar bears, whales and other mammals and sea birds who depend on the ice may crash if sea ice is regularly absent. And as water in its bright-white solid form is much more effective at reflecting heat from the sun, its rapid loss is also accelerating global heating.

Glaciers are also melting. If emissions continue on their current trajectory, smaller glaciers will shrink by more than 80 per cent by the end of the century. This retreat will place increasing strain on the hundreds of millions of people globally who rely on glaciers for water, agriculture, and power. Dangerous landslides, avalanches, rockfalls and floods will become increasingly normal in mountain areas.


Rising oceans, rising problems

All this melting ice means that sea levels are rising. While seas rose globally by around 15cm during the 20th century, they’re now rising more than twice as fast –- and this rate is accelerating.

Thanks to research from myself and others, we now better understand how Antarctica and Greenland’s ice sheets interact with the oceans. As a result, the latest report has upgraded its long-term estimates for how much sea level is expected to rise. Uncertainties still remain, but we’re headed for a rise of between 60 and 110cm by 2100.

Of course, sea level isn’t static. Intense rainfall and cyclones – themselves exacerbated by climate breakdown – can cause water to surge metres above the normal level. The IPCC’s report is very clear: these extreme storm surges we used to expect once per century will now be expected every year by mid-century. In addition to rapidly curbing emissions, we must invest millions to protect at-risk coastal and low-lying areas from flooding and loss of life.

Ocean ecosystems

Up to now, the ocean has taken up more than 90 per cent of the excess heat in the global climate system. Warming to date has already reduced the mixing between water layers and, as a consequence, has reduced the supply of oxygen and nutrients for marine life. By 2100 the ocean will take up five to seven times more heat than it has done in the past 50 years if we don’t change our emissions trajectory. Marine heatwaves are also projected to be more intense, last longer and occur 50 times more often. To top it off, the ocean is becoming more acidic as it continues to absorb a proportion of the carbon dioxide we emit.

Collectively, these pressures place marine life across the globe under unprecedented threat. Some species may move to new waters, but others less able to adapt will decline or even die out. This could cause major problems for communities that depend on local seafood. As it stands, coral reefs – beautiful ecosystems that support thousands of species – will be nearly totally wiped out by the end of the century.

Between the lines

While the document makes some striking statements, it is actually relatively conservative with its conclusions – perhaps because it had to be approved by the 195 nations that ratify the IPCC’s reports. Right now, I would expect that sea level rise and ice melt will occur faster than the report predicts. Ten years ago, I might have said the opposite. But the latest science is painting an increasingly grave picture for the future of our oceans and cryosphere – particularly if we carry on with “business as usual”.

The difference between 1.5°C and 2°C of heating is especially important for the icy poles, which warm much faster than the global average. At 1.5°C of warming, the probability of an ice-free September in the Arctic ocean is one in 100. But at 2°C, we’d expect to see this happening about one-third of the time. Rising sea levels, ocean warming and acidification, melting glaciers, and permafrost also will also happen faster – and with it, the risks to humanity and the living planet increase. It’s up to us and the leaders we choose to stem the rising tide of climate and ecological breakdown.

Mark Brandon, Professor of Polar Oceanography, The Open University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.