Archive for February, 2010

Worldmapper selection

February 28, 2010

Worldmapper has moved on a lot since I last looked — which was at least a couple of years ago. These are the cartograms which “re-size each territory according to the variable being mapped”. There’s now a huge selection of maps and a handful of animations. Here are a few good ‘uns. You need to have at least a rough mental idea of these two maps (land area and population) to make sense of the others:

Land area

Total population

© Copyright 2006 SASI Group (University of Sheffield) and Mark Newman (University of Michigan). Same goes for all maps below the fold.

I’ll resist the temptation to provide commentary, as most of these speak for themselves.


Haiti— there was a tsunami?

February 25, 2010

The BBC says so:

Localised, but 3-metre waves and three deaths. Generally wouldn’t expect this from a magnitude 7.0 earthquake with an onshore epicentre, but the quake was close enough to a sufficiently steep submarine ridge to set off some ‘local landslides’.

The audio clip on the BBC page has more detail.

Of course not very significant compared to the onshore devastation and loss of life, but at least it provided a good test for the Noaa’s DART tsunami warning system. It also revealed a worrying— but presumably remediable— lack of tsunami awareness in some of the local population, who were busy taking pictures rather than getting out of the way.

And following on from the 2004 Indian Ocean Boxing Day earthquake, it might act as a reminder that major tsunamis have happened in the Caribbean before and might (or might not) happen again.

Meningitis in Africa

February 21, 2010

In the developed world, meningococcal meningitis is mostly a ‘sporadic’ disease. About 10% of us carry Neisseria meningitis as resident bacteria at the back of our throats. If we’re very unlucky, a few cells may find their way into the blood and circulate to the membranes lining the brain- the meninges– and establish a breeding population.

When this happens, it’s bad news.

Although readily treatable with antibiotics, mortality rates from meningococcal meningitis are relatively high, even in western countries. Thankfully it’s rare. Occasionally, short-lived outbreaks of the disease occur in situations where groups of people live in close proximity and share respiratory or throat secretions (intentionally or otherwise). These infrequent disease clusters typically occur in schools or universities, but don’t usually affect more than a handful of people at a time.

In some parts of the world, however, meningoccal meningitis behaves very differently. The worst affected of these regions is the so-called meningitis belt of sub Saharan Africa, where the disease can occur in devastating seasonal waves which sweep through the population. The worst ever epidemic— in 1996— killed around 25,000 people. The 2009 season was a bad one, too; despite vigorous control efforts there were over 1500 deaths.

Why does the disease occur in epidemics in Africa, but not in Europe or North America— and why are these epidemics seasonal? And what can we do about it? These are interesting questions if you have interests in both health and the Earth sciences. If you haven’t, stop reading now.

News/Death Ratios

February 14, 2010

Back in May 2009 Hans Rosling introduced the world to a new indicator for media hype: the News/Death ratio. His example compares the frenzied media reporting of swine flu to deaths from tuberculosis over the same thirteen day period; the point being that the former was attracting extensive news coverage despite a trivial impact on global mortality, while the latter was responsible for numerous under-reported deaths. So why not extend his idea and look at some other stuff?

MMR and climate change: the missing link

February 7, 2010

Andrew Wakefield’s comeuppance part 1 seems very likely to be followed by part 2 (“the strike-off”) later this year.

I’ve just read some of the detail of the recent findings: it won’t be a minute too soon. He is not, of course, the only party at fault. The Lancet published a shoddy paper— twelve patients! Twelve selected patients!— with the retraction last week amounting to an historically belated stable door closure. The government and the medical profession were patronising, clumsy and ineffectual in their efforts to reassure the public. But perhaps the biggest villain of the piece is what Ben Goldacre says. The meeja.

Meanwhile, someone at GQ magazine has written this.