Originally posted at Skeptical Science on 31 October 2013

We think we have done more than we have done and we haven’t understood how much we have to do. Hans Rosling

Hans Rosling is a Swedish medical doctor and statistician who is determined (in his own words) “to fight devastating ignorance with a fact-based worldview that everyone can understand”.

Here is a video of him giving a talk on September 28th, 2013 at a public forum that introduced the latest IPCC report. The meeting was hosted by the International Geosphere-Biosphere Programme in Stockholm.

During the talk he asks a couple of questions, one on how many more children there will be in the year 2100 compared to today and another on what percentage of world energy is produced by solar and wind. I was in the minority that got the first one correct, but only because I had already seen one of Rosling’s earlier talks. On the second question, I was among the majority that got the answer wrong. How will you do?

Here are the main points that stood out for me:

• He commends the IPCC AR5 report as being “as good as science can do”. He says the difficulties of communicating the uncertainties in climate science are far greater than for other science communication problems that he has been involved in professionally, such as smoking and cancer. He goes as far to say that, in this regard, climate science will be a model for other sciences. That’s high praise indeed from one of the world’s expert science communicators.

• Using sea-level rise as an example, he points out how the effects of climate changewill be felt very differently in different parts of the world. In northern Sweden, post-glacial rebound means that the land may rise faster than the sea level and no effect will be felt at all this century. On the other hand, in Bangladesh, sea level rise will be catastrophic, displacing millions from their homes and farms unless extraordinary adaptation measures are taken. (3:15)

• He places human development and population in historical perspective. He shows how rising prosperity, driven in large part by coal, has reduced the appalling levels of child mortality that existed prior to industrialization. He says: “There is a myth that humans used to live in ecological balance … they died in ecological balance”.  (7:15)

• Despite the economic emergence of China over recent decades, the Chinese today produce less CO2 per capita than Americans or Britons did in 1900. (11:45)

• Extreme poverty today results in the deaths of seven million children per year. According to Rosling, this is, for now, a much bigger problem than climate change. “If you burn coal, you save children”. (16:10)

• He places the responsibility for dealing with climate change firmly on the shoulders of the rich countries. How can Swedes tell Mozambique not to build coal power stations, when the there is still a coal power station operating just one kilometre from the Swedish Academy? (13:00) And how can we dare tell the emerging economies like China that they cannot aspire to live like we do? (16:30)

We, all of us, have areas of “devastating ignorance” that need to be filled in with facts and new perspectives. Listening to a Hans Rosling is always entertaining, but it can also be rather unsettling.

As for the two quiz questions:

1) According to Rosling, we have already reached “Peak Child” with about 2 billion people 15 years old or younger. Although the population will continue to grow to 10 or 11 billion, the absolute number of children is likely to stay steady. Only about 10% of the public in Sweden and the UK know that, Most people in those countries assume that the number of children will greatly increase.(8:15)

2) Less than 1% of the world’s energy is currently generated by wind and solar power. In a survey of the UK public, 70% of people believe that the amount is five times or more that. (18:00)

There are more quiz questions on this BBC website

Thomas Stocker’s talk on the IPCC AR5 WGI Summary for Policymakers report followed Rosling’s talk and is also well worth watching.

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