UN confronts rise of climate change denial

This week the United Nations is to upgrade the probability that humans are radically altering the climate to ‘extremely likely’. But doubt about global warming is gaining ground.

Since the Industrial Revolution, we have burned around half a trillion tonnes of fossil fuels. The world’s average temperature has increased by roughly one degree celsius in the past century, while water levels have risen by 20cm. Climate change is real, humans are responsible, and it is going to get much worse.

These are some of the conclusions to be found in a report from the United Nations climate panel, the IPCC, which will be released this week. UN climate scientists have upgraded their confidence about whether man is responsible for climate change from ‘very likely’ to ‘extremely likely’. In the coming 100 years temperatures are expected to rise between 1.5°C and 6°C.

The report is not all bad news. While the IPCC’s warnings about the fact of global warming are more confident, scientists are slightly more optimistic than they were six years ago about how extreme the change will be. And the report acknowledges that climate change has slowed markedly over the past 15 years – although the authors emphasise that this is down to temporary natural fluctuation rather than a reversal of previous trends.

All of these estimations are based on computer models, which climate scientists admit are imprecise: the error margins in specific predictions about the effects of climate change tend to be fairly wide. But about the fundamental fact that the world is getting hotter, the report expresses no doubt.

Yet the public do not share this confidence. Far from it: according to a new survey, one in five people deny that temperatures are rising at all, with only just over 50% convinced that man-made climate change is real.

This attitude is regularly reflected in the media. Over the weekend, several British newspapers ran articles by climate change sceptics, who see global warming as a ‘scientific blunder’ and even a ‘scam’.

Sceptic uptick

Why, ask these commentators, should we trust a scientific community which has proved itself so error-prone in the past? The IPCC once predicted that by 2013 the Arctic would be totally melted in summer; instead, it has two million square miles of ice. This report is already an admission that some previous warnings were exaggerated, so why should we accept the ones that have replaced them? Perhaps, they say, it is time to give the minority a hearing.

That is dangerous talk, caution climate scientists. Of course the experts do not always get it right, but predicting the future is never an exact science. Nobody ever claimed otherwise. With such a wide consensus that global warming is real, this blithe scepticism is irresponsible – perhaps, for mankind, even suicidal.

You Decide

  1. Should global warming be the top priority of 21st century governments? If not, what should?
  2. Why do you think so many people are unconvinced that climate change is real?

Activities

  1. Write down three ways in which you could live in a more environmentally sustainable way. Compare your answers with the rest of the class.
  2. Draw a simple diagram explaining how global warming occurs.

Some People Say...

“Public opinion is irrelevant when it comes to science.”

What do you think?

Q & A

How scared of climate change should I be?
That’s a very tough question. While there’s a strong consensus on the reality of climate change, opinions vary on how bad it will be. But even the conservative predictions are chilling: crop failures will cause famine and spark a migration crisis, coastal cities like New York and Mumbai will experience devastating flooding and a third of Earth’s species could become extinct.
Is there anything I can do to prevent this?
Living a greener lifestyle is one way of doing your bit. Use as little energy as possible; cycle, walk or use public transport; recycle as much as you can. But since top-down change will also be necessary, it’s worth putting pressure on local politicians too. If you’re really committed, you could even consider a career in environmental law or developing green energy.

Word Watch

Industrial Revolution
A period of rapid social change which began in the late 18th century, sparked by technological innovations such as the invention of steam power. The factories that sprang up as a result of this burned fossil fuels, producing enormous amounts of carbon dioxide (a greenhouse gas which traps heat in the Earth’s atmosphere) as a by-product. The planet’s carbon dioxide levels have increased by roughly 40% in the last century.
IPCC
The Intergovernmental Panel on Climate Change has produced just five major reports since 1992, the last one coming six years ago.
Fluctuation
The Earth’s climate is constantly changing in subtle and intricate ways. First there are glacial and interglacial periods, which last for millions of years. Within those ages the temperature fluctuates from ice ages to warmer periods, and the planet also goes through hotter and cooler periods on a much smaller timescale. The slowdown of global warming since 1998 is apparently partly down to volcanic activity.
Error margins
Computer models have to account for many different variables which impact on the overall prediction, and each of these variables is impossible to predict exactly. Scientists put in the upper and lower limits of what they believe it is reasonable to expect for each piece of data. So these models produce a wide range of scenarios rather than one definitive prediction.

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