Friday, 3 May 2013

An End to Magical Thinking on Climate Change?

Mickey Mouse (c) Disney
Quick quiz: What's the link between the recent measles outbreak in the UK, fiscal austerity as a way to restart economic growth, and the news that global CO2 emissions are about to surpass the 400 parts per million mark for the first time in millennia?

Answer: All three reflect the dominance of magical thinking - or rather, the willingness of citizens and policy makers to make decisions based on supposition and gut feel rather than an understanding of cause and effect or relying on data.

Humans are notoriously bad at math.  It is extremely challenging for most people to identify more than five items in a group without counting them out.  We can rarely perform more than the most basic calculations in our heads.  Statistics, percentages, data analysis - these concepts do not come naturally.

This is a problem because society needs to base its important decisions on sound information.  When we make major decisions using bad information, the results can be catastrophic. As a result, we need to be very careful when we make decisions that affect the rest of society. Science and data are the order of the day, checking and double-checking, not gut feel or wishful thinking.  Unfortunately, that does not always happen.

In 1998, news outlets in the UK reported the results of a study that claimed a link between the measles-mumps-rubella (MMR) triple vaccination and autism.  Other researchers immediately questioned the study, and no one demonstrated a verifiable cause-and-effect relationship between the vaccine and the condition. It didn't matter.  Thousands of parents, responding to screaming headlines, refused to have their children immunised, believing that somehow avoiding vaccinations would make them safer.

Fast forward to 2013.  The original report has been thoroughly repudiated, and the doctor who published the research has been struck off the General Medical Council register. Meanwhile, over 1,000 children have contracted measles, a dangerous and easily preventable illness and many more are at risk.  The British government is now spending vast sums on a massive vaccination "catch up" campaign to halt the spread of measles, as well as mumps and rubella. These are diseases that were nearly wiped out in Western countries a generation ago.  They have made a comeback  thanks to over-reliance on shoddy data, and now all of us are paying to clean up the mess, not least the families of children who have contracted this horrible disease.

In 2010, Harvard economists Carmen Reinhart and Kenneth Rogoff published a research paper claiming a link between countries' national debt levels and economic growth. In particular, they argued that growth falls dramatically when debt levels exceed 90%.  No matter that the paper had not undergone peer review, that other economists questioned the report and that other researchers were unable to replicate the results.  And no matter that it was hard to work out a cause-and-effect mechanism that would kick in only above a certain threshold.  The report was seized upon by fiscal hawks at think tanks and in governments across Europe and in the United States to justify massive government spending cuts.  The resulting "age of austerity" has seen a change of  government in Italy, riots on the streets of Athens, cuts to public services and benefits in the United Kingdom, and across-the-board budget cuts in everything from air traffic control to national parks in the United States.  One might argue that politicians would have embarked on these measures in any event, but the fact remains that this paper provided intellectual cover and was cited far and wide to justify fiscal cutbacks.

Fast forward to 2013. The original report claiming a link between debt levels and economic growth has been debunked due to questionable methodological techniques and a particularly glaring Excel formula error.  Even the International Monetary Fund, which championed "structural adjustment" and similar austerity measures for developing countries in the  1980s and 1990s, has begun to rethink its initial support of fiscal austerity.  In the meantime, economic output remains anaemic, unemployment has skyrocketed across southern Europe, and in the UK slow growth means that government debt has risen not fallen.

Whether it's in social sciences like economics and sociology, or in the physical sciences like biology and physics, we can make the most confident predictions when there is a logical link between cause and effect, when the research is subject to peer review, and when other resaerchers using the same data reach similar conclusions. To quote the late astronomer Carl Sagan,

"What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence."

And so to climate change.

Scientists have for decades been researching the link between human-induced greenhouse gas emissions, rising global temperatures, and changes to the global and regional climate. Every ten years, the UN-mandated Intergovernmental Panel on Climate Change (IPCC) publishes a summary of these research findings, along with recommendations for government action.  The IPCC is comprised of thousands of the world's best climate scientists - physicists, meteorologists, chemists, computer modelers.  Their research is published and subject to international peer review.  They flag past errors and describe how they have subsequently updated their findings.  The findings and recommendations represent the consensus view of  over 120 governments, are cautiously worded and full of caveats regarding potential uncertainties.

The IPCC assessments reports are a triumph of science and data over gut feel.  The process is slow, methodical and cautious.  After all, climate change is a global problem that affects almost every aspect of how we live, work and play.  It is important to make sound decisions based on good information.

So what to make of the news that global CO2 concentrations are about to exceed 400 parts per million for the first time since the Pliocene Era, 3.5 to 5 million years ago?

More magical thinking, I'm sorry to say.  Politicians worry that setting ambitious targets to tackle climate change will cause economic hardship and continue to subsidise fossil fuels, ignoring the costs of climate related disasters like heatwaves and drought, floods and storms, and irreparable damage to our forests and other ecosystems.  Journalists looking for balance have given equal voice to a handful of climate skeptics and recognised scientists who quote the peer reviewed IPCC data.  And the general population, unable to see directly the link between their lifestyles and rising global temperatures and lacking any direct incentives to take action, refuses to change its behaviour.

But all is not lost.  The sudden push to vaccinate children in the United Kingdom shows that we can overcome magical thinking to make rational decisions.  The rapid shift in opinion against a once ubiquitous study on debt and economic growth shows that people can change their minds and consider alternatives when new data becomes available.

The IPCC 5th Assessment Report will be released in late October 2013.  As the impacts of climate change become more apparent to people around the world, I'm hopeful that governments, businesses, communities and individuals will review the IPCC findings, abandon gut feel, and seize this latest opportunity to tackle climate change and embrace a lower-carbon future.

Previously: Science- It Works on Mars and on Earth
Previously: Welcome to the Reality-Based Majority