We think of Canada as a long way north – but half its population lives south of Milan

Toronto: same latitude as Nice. Who new? Image: Getty.

This article was originally posted on David Taylor's data visualisation blog Prooffreader.com in November 2013. David very kindly agreed to let us repost it here, which is pretty lovely of him.

Canada is farther north than the United States: everybody knows this, and for the most part it's true.

But an article in Monitor on Psychology says people tend to take these geographical mental shortcuts too far: most Americans are surprised to find that all of Florida is farther south than the Mexican border, for example.

So let's see how much of the United States is below Canada's most southerly city, Windsor, Ontario (I won't cheat and count the little islands in Lake Erie that belong to Canada):


For the record, the red area comprises 22 per cent of the surface area of the contiguous United States (38 per cent if you include Alaska), and 15 per cent of its population. Windsor is just 25 km further north than the California-Oregon border.

The paper also states that both Americans and Canadians tend to imagine Europe to be more southerly than it is in relation to them: they equating Spain's latitude with the southern states, for example. Let's have a look, without that pesky Atlantic Ocean in the way:


Once again using the online tool Mapfrappe, I've marked the Latitudes of Windsor and of the 60th parallel, which divides the Prairie provinces from Northern Canada.

You'll notice Windsor, which has some cold winters, is even with northern Spain, which decidedly doesn't. That's another mental shortcut we all share: north = cold. But it's not that simple when you have a nice Gulf Stream warming your coastline, as Europe does.

The geographical comparison was less surprising to me than the demographic one. In 2013, I posted a blog about Canadian population by latitude, whose data was a little coarse because Canada Post and Statistics Canada have copyrighted the most finely detailed geographical boundaries used in the census.

But a wonderful reader pointed me to the ISLCP II Project, which lists the population of the entire planet for every quarter-degree of latitude and longitude (albeit from 1995, but I'll take it). Have a look at the relative populations by latitude of the United States, Canada and Europe:

The most northerly Canadian city with a population of over 500,000 is Edmonton, Alberta: it's at about the same latitude as Dublin, Manchester and Hamburg. Around 15 per cent of Europeans live farther north than this. (The demarcation of Europe and Asia is fuzzily defined; I chose it as including Istanbul and Moscow, which is north of Edmonton.)


In fact, the median latitude of population in Europe is nearly 4 degrees higher than in Canada – that's around 400km.

Thanks to these histograms I realized I'm as susceptible to that misfiring geography heurism as anyone: in my mind, Hawaii was about the same latitude as Sacramento, California. But it's over 500km farther south than the mainland United States.

David Taylor is a Montreal-based writer, who runs the data visualisation blog Prooffreader.com.

Editor's note: the calculation that the median Canadian lives at between 45 and 46 degrees latitude, roughly on a par with Milan, is CityMetric's own. If we've screwed up, it's our error, not David's.

 
 
 
 

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.