Switching off denial: a guide

Danny Chivers presents the New Internationalist guide to debunking the myths of the climate change deniers.

If you’re a sceptic, then I salute you.

Sceptics are people who don’t take things at face value; they demand facts, and are ready to change opinions based on the weight of evidence, even if that goes against personal preferences or beliefs. I like to think that I’m a bit of sceptic myself (although I’ll need a bit more evidence before I’m sure).

Deniers, on the other hand, refuse to accept evidence that conflicts with their personal beliefs, desires or ideology. People in denial gather reasons and excuses, however flimsy, that allow them to not believe in whatever unwelcome truth they’re trying to avoid.

No serious sceptic could doubt that human-caused climate change is real, and serious – the evidence is just too overwhelming. However, many people are still in a state of denial over climate change, for a wide range of reasons. Fortunately, opinion polls show that the majority of the public accept the reality of the climate problem1; however, the number of people who take climate change seriously seems to be slipping back in some countries.2 If we want to keep building a global movement for climate justice, then we need to face up to the problem of denial.

Here are some handy weapons for tackling climate change denial head-on.

Myths about the basic science

‘CO2 isn’t a greenhouse gas’

This is basic, well-established science that is difficult to deny – but some people still like to have a go. Carbon dioxide’s heat-trapping properties were first discovered by John Tyndall in the 1860s.3 The warming powers of CO2 can be demonstrated simply by filling a plastic bottle with the gas, shining a lamp on it and measuring its temperature compared to a bottle filled with ordinary air. The BBC do it in a two-minute video here: news.bbc.co.uk/2/hi/8394168.stm

‘When the climate changed in prehistoric times, the warming came first, then the CO2 rose afterwards’

Figure 1: Historic CO2 and temperature data from the Vostok ice core

Source: Petit et al 1999 Nature

Evidence from ancient ice cores, tree rings, coastlines, and the ocean’s depths provide us with a pretty decent picture of how temperatures, sea levels, and the amount of CO2 in the air have changed over the last few tens of millions of years. The results are fascinating – the Earth has swung periodically between colder and warmer periods over the eons (see Figure 1). These huge changes were initially triggered by tiny fluctuations in the Earth’s temperature – the sun might go through a slightly warmer or cooler phase,4 or kinks in the Earth’s orbit might take the planet out a little further or in a little closer.5 The planet would then warm or cool gradually, over hundreds or thousands of years. Then suddenly, this would transform into rapid change, switching the planet from cool to warm or vice versa.

Why the sudden flip into rapid change? Well, as the planet warms up, carbon dioxide and methane are released from plants, soils and oceans. These gases create a greenhouse effect which leads to more warming and thus the release of more CO2 and so on until the whole climate has changed completely. This explains why temperatures started to rise first, and then CO2 followed.

Imagine that a group of gibbons escape and run amok at a zoo. They cause plenty of chaos by themselves, but the zookeepers don’t round them up quickly enough and so the gleeful gibbons started releasing the chimpanzees from their cages, who then start letting the other animals loose, until the whole thing spirals completely out of control. Looking back on this afterwards, it’s true that the zoo was already in chaos before the chimpanzees escaped; but it doesn’t mean that it’s therefore fine to release as many chimpanzees into your own zoo as you like, without expecting any consequences…

‘Many scientists don’t agree with the consensus on climate change’

According to a 2009 survey, 97 per cent of published climate scientists believe that humanity is changing the climate.6 The basic underlying science linking humanity’s greenhouse gas emissions with climate change is as well-established as the link between smoking and lung cancer, or HIV and AIDS – some people still deny these connections, but no-one takes them seriously. There is disagreement and debate around the precise effects of climate change; but the facts that it’s happening, it’s serious, and it’s caused by humans are well established and agreed by all but a small handful of scientists.

Unfortunately, this small group gets a huge amount of attention, making them seem more numerous than they really are – and a lot of this is to do with the funding and support they receive. This isn’t to say that the climate contrarians are simply in it for the money. I’m sure most of them believe in the things they say. But they wouldn’t have such prominence and status without the backing of certain wealthy and powerful individuals, political groups, media outlets and corporations with a (short-term and profit-driven) interest in preventing action on climate change. The mainstream media have a tendency to set up head to head ‘debates’ between climate scientists/campaigners and climate change deniers, which creates the false impression that the science is still disputed. It’s about as useful as watching a debate on how to solve the African AIDS crisis between an experienced Ugandan health campaigner and someone who believes that HIV is spread by evil pixies and can be cured by eating spaghetti.

Quick snippets of falseness #1

‘So what if ships can get through the Arctic Northwest Passage? It was open in the early 1900s too!’

It’s true that the Northwest Passage – the icy stretch of Arctic Ocean linking the Atlantic and Pacific Oceans above North America – was first navigated by Roald Amundsen in 1903-1906. Note, however, that it took him three years to get through! This passage used to be completely impassable to ships for most of the year; now, climate change has melted enough Arctic ice to make it an economic shipping route, triggering sovereignty disputes between Canada and other countries.

Myths about temperature rise

‘The world isn’t really warming up’

Figure 2: Global warming since 1850, an average computed from ten different sources. The ‘0’ line is the 1990 - 2000 average temperature

Source: Adapted from a graph from www.skepticalscience.com under a CC licence

Figure 2 shows the global air temperature over the last 150 years; the second adds in the ocean temperature since 1950.

So the temperature changes we are feeling on land are small fry (if you’ll pardon the expression) compared to the heating of the oceans. Meanwhile, cyclical weather patterns like El Niño and La Niña move heat back and forth between the oceans and the air in an irregular fashion – a major reason why atmospheric temperatures aren’t rising in a nice neat line. For example, a strong El Niño shifted a lot of heat from the seas into the air in 1998, causing a spike in air temperatures. When temperatures in the following years reverted back, climate deniers started going on about how global warming had ‘stopped’. Of course it hadn’t – it was just that the heat was being stored in the ocean rather than the atmosphere, as Figure 3 clearly shows. The top ten hottest years in recorded human history all happened in the last twelve years, with 2005 and 2010 tied for the hottest ever.9

‘The world cooled down between 1940 and 1970’

This isn’t true, but is based on something genuinely interesting. Global warming did plateau for a bit between the 1940s and the 1970s, due to the phenomenon of ‘global dimming’ – a type of industrial pollutant called sulphate aerosols were partially blocking the sun’s rays. This lasted for a while until the ongoing build-up of greenhouse gases – combined, ironically enough, with a reduction in sulphate pollution from power stations – eventually swamped the dimming effect and the temperature began to rise once more.10 You can see this flattened period on the graph in Figure 2.

‘The temperature data are fixed/flawed/manipulated’

Figure 3 – Total Earth heat content from 1950

Sources: Murphy et al 20097, Domingues et al 20088, graph by skepticalscience.com under a CC licence

To somehow tamper with or subvert the data from around 7,000 different measurement stations and satellites, which are processed via three different major organizations with hundreds of staff, would require an utterly fantastic level of conspiracy. Nonetheless, in 2010 a procession of (mostly online) commentators claimed that a series of hacked emails from the Climate Research Unit at the UK’s University of East Anglia contained evidence of just such a conspiracy (which they imaginatively dubbed ‘Climategate’). Three separate independent enquiries trawled through the emails and found evidence of nothing more than a few scientists occasionally being a bit rude about some of their colleagues, using some unhelpful jargon and having the odd moan about incessant public requests for information.11 However, there was one useful outcome: much more of the raw temperature data has since been made public, to avoid similar accusations in the future.12

‘But it’s cold today…’

Although the average global temperature is rising, that doesn’t mean that everywhere is getting hotter at the same rate. The global climate system is complicated; some places are heating faster than others, and some may even cool down depending on ocean currents and wind patterns.

The difference between climate and weather is important here. Climate change is a gradual, long-term process; weather is about short-term, day-to-day changes due to local patterns of wind, evaporation and ocean currents, and is more unpredictable. A few weeks of cold weather in one location tells us little about long-term global temperature change – that’s why we need all those thousands of temperature measurement stations taking decades’ worth of readings. Those measurements are telling us that every time there’s a bit of unusually cold weather somewhere in the world, it’s being outweighed by many more examples of unusually hot weather elsewhere, and so the overall trend is of a warming planet.

Quick snippets of falseness #2

‘The glaciers are growing, not shrinking!’

In any given year, some glaciers will grow a bit, because of local cold weather or extra snow. Professional deniers point at this minority of growing glaciers and pretend that all the rest don’t exist. Once you look at all the world’s glaciers at once, the shrinking trend is clear – they’ve lost over 20% of their mass since 194526.

Myths about other things that might be causing it

‘Volcanoes produce more CO2 than humans’

This one’s just nonsense – humanity is responsible for at least 60 times the CO2 of volcanoes.13 This point was firmly underlined when the Icelandic volcano Eyjafjallajokull erupted in March 2010; the resulting ash cloud led to the grounding of planes across Europe for several weeks, preventing far more carbon dioxide than the volcano was emitting. It created a net saving of around 50,000 tonnes of CO2 per day.14

‘It’s caused by the sun’

Figure 4: Global temperature (red) and Total solar irradiance (blue)

Source: Data from NASA, Solanki and PMOD16, graph compiled by www.skepticalscience.com under a CC licence

The sun does occasionally go through periods of increased activity, where it puts out a bit of extra heat. However, all the extra sun activity of the last 150 years can only account for a small amount of the warming we’ve seen in that time – the rest must be due to something else. Sun activity has remained roughly level since the 1960s, and has, in fact, been cooler than usual since 2003 – see Figure 4. This is all well-measured and non-controversial.15 So it can’t be due to the sun alone.

‘It’s caused by cosmic rays/something else’

There are other ‘theories’ out there, but with little or no evidence to back them up. Of course, in order to overturn the existing theory of human-made global warming, they’d need to have a mountain of contrary evidence that explains why the current scientific explanation isn’t correct. For example, if you decided that the real reason why leaves fall off trees in winter is that they’re being tugged off by mischievous squirrels, you’d need a bit more evidence than a photo of a squirrel sheepishly clutching an oak leaf. None of the other supposed explanations for climate change can provide the evidence (for example, the ‘cosmic rays’ idea comes from a handful of largely discredited scientific papers about the possible effect of cosmic rays on cloud formation17).

Quick snippets of falseness #3

‘There’s a new study that says the climate scientists were wrong’

New research is being done all the time to improve our understanding of the details of climate change. Sometimes this will contradict earlier ideas about certain climate change effects – for example, we now know that global warming isn’t likely to produce more frequent tropical storms, just more powerful ones. But it doesn’t contradict the underlying theory of human-made climate change – it just helps us to improve our understanding of its effects.

Myths about the effects of climate change

‘The Antarctic ice is growing, not shrinking’

This is true for certain areas of Antarctica – and, intriguingly, it actually gives us more evidence for global warming. Increased evaporation caused by higher temperatures has led to more snowfall in some parts of Antarctica, and thus thicker ice cover in these areas (usually inland). Closer to the sea (which is warming faster than the air) the ice is retreating.

‘Climate change has good effects, not just bad ones!’

True – up to a point. Warmer winters in some countries will mean fewer people die from cold. Increased temperatures have made it easier to grow crops in some regions. Sadly, these small pockets of positive effects are hugely outweighed by the negative ones.18 We have built almost all our settlements in places that are comfortable and fertile in our current climate, and our ways of growing food are carefully adapted to the weather we’ve been used to for thousands of years. Rapid changes in the Earth’s climate are already starting to throw this out of kilter – hence increasing deaths from storms, floods and famines. Even if climate change makes some places more comfortable to humans, do we expect everyone to migrate to the limited number of places where this is so?

‘Climate change is a problem, but there are bigger problems that we need to tackle first’

This argument offers a false choice – we can (and should) tackle the problems of climate change, poverty, healthcare etc all at the same time. Many of these problems have the same root causes – the relentless pursuit of profit and economic growth over people’s real needs – so it makes sense to work on them all together.

Climate change is making many of the world’s problems much worse – Kofi Annan’s Global Humanitarian Forum19 found that climate change threatens all eight of the Millennium Development Goals20 and is making it much harder to tackle global poverty and disease. Any progress we make in these areas will be swept away by climate change, unless we act to prevent its worst effects.

‘We can’t trust the computer models’

While the ‘big picture’ climate change predictions (increased temperatures, more evaporation, melting ice caps and rising seas) are based on observed results and the prehistoric record, the more detailed projections (how much climate change, where, and by when) are based on computer models. These models are constantly checked and improved, and tested against real-life scenarios to make sure they’re as accurate as possible, but there are always going to be some uncertainties. This is why climate scientists talk in terms of probabilities and risks; no-one knows all the details of what’s going to happen as the climate changes, but these models can show us the most likely trends and give us some useful indications and warnings.

Some use this uncertainty to argue against taking action to tackle climate change and spending money on climate solutions, saying that it might not be as bad as we think. The problem with this argument is that we do know it’s going to be bad. We know because it’s already bad – people are suffering in floods and droughts, we’re losing species left, right and centre, and over 300,000 people are dying every year as a result of climate change.21 We don’t need the models to tell us that if we keep on pumping out the polluting gases that caused this mess, things are going to keep getting worse.

Quick snippets of falseness #4

‘CO2 makes plants grow faster, which will slow down global warming’

There’s no sign of this ‘fertilizer feedback’ actually taking place on any significant scale. This is probably because CO2 only speeds up plant growth if the plant also has everything else it needs to grow bigger – water, soil nutrients, light, space etc. Plants are the size they are probably because they’re lacking one of these other factors, not because they don’t have enough CO2 (and climate change is likely to make things worse by reducing the amount of water available to many plants).

Other distraction tactics

‘It’s too late, we need to adapt to climate change instead’

We’re already committed to a certain level of climate change, and so some adaptation will be absolutely vital. If we’re serious about climate justice then the nations most responsible for causing climate change should be providing funds and technology to the people on the receiving end, to help them cope with rising sea levels and more serious floods, storms and droughts.

However, adaptation cannot be a replacement for reducing greenhouse gas emissions. ‘Adapting’ to more serious levels of climate change would involve coping with mass food shortages, the loss of dozens of major cities, finding new homes for hundreds of millions of people and countless deaths from starvation, conflict and disease. Runaway climate change could leave us with a largely uninhabitable planet.

Even if it were possible, adaptation on this scale wouldn’t be cheaper or easier than cutting CO2 emissions – even conservative estimates like the British government’s Stern Review place the costs of climate impacts far higher than the costs of prevention. It’s like saying ‘it’s just too much effort to hit the brakes, I’m sure my car can adapt to that brick wall’.

Leading climate scientists are telling us that we still have a decent chance of avoiding runaway climate change, but only if we act fast. Telling ourselves it’s too late is just another form of denial – an excuse to avoid action.

‘It’s all about population growth’

It’s true that the more people there are on the planet, the fewer resources there are to go around. However, birth rates in most Northern nations are low; most population growth is occurring in poorer countries. The current per capita consumption rate in these countries is very small – for example, the average Canadian uses the same amount of energy per year as 20 Tanzanians. The wealthiest 20 per cent of the world’s people use over 70 per cent of the energy. With regard to climate change it is far more urgent to reduce consumption levels in the North than birth rates in the South.

High birth rates are strongly associated with poverty, hunger and a lack of access to healthcare. They are also connected to a lack of women’s rights and restricted access to health information and contraception. If we want the world’s population to stabilize sooner rather than later, we need to support people around the world – especially women – to claim more rights, greater dignity and full control over their lives. However, we also need to urgently reduce emissions in the North!

‘Scientists exaggerate the risks of climate change to get more funding’

This is completely back to front – if a scientist found real evidence that contradicted the accepted theory of human-made climate change, do you think they’d have any difficulty finding funding? Successful climate change deniers can already rake in hundreds of thousands of dollars just to present their opinions, without the backing of any reputable science.22

A survey of climate scientists by the Union of Concerned Scientists in 2007 found that 58 per cent of respondents had experienced political pressure to water down their scientific findings.23 The 2007 Intergovernmental Panel on Climate Change (IPCC) report was stripped of many ‘undesirable’ passages by politicians before it could be published, including warnings about the likely impacts of climate change on North America and references to the risk of runaway climate change.24 More recently, the outspoken IPCC chair Rajendra Pachauri has endured a barrage of false claims of fraud and corruption from climate deniers.31 There is plenty of pressure on climate scientists to change their research – but nearly all of it is pushing them to tone down their message, and not to speak out.

How to talk to a climate change denier

If they’re just misinformed, or don’t want to believe it for personal reasons, then you may have a chance of changing their mind. Don’t expect to win them over all in one go – be sensitive, explain the facts as simply and clearly as you can and try not to get frustrated. Remember that the reality of climate change is a huge and scary thing to get our heads around – it’s a complex, decentralized and enormous threat that can’t be easily blamed on any one single organization or person. Accepting it fully means we need to make genuine changes in our lives and start working actively to stop it, which is a significant responsibility to take on.

Try being gently challenging rather than staying on the defensive – do they have a coherent argument as to why climate change isn’t happening, or isn’t serious? Most people don’t – they have a collection of soundbites or excuses that they use to justify not thinking about the problem properly. Don’t be too confrontational though – the aim is to make them seriously think the matter through and change their minds by themselves, rather than for you to ‘win the argument’. Be sympathetic rather than accusatory – make it clear that the fault doesn’t lie with the person you’re speaking to, but the public misinformers and their corporate funders.

If you’re debating with a ‘hardline’ denier – someone with a strong vested interest, or who’s being paid to spout an anti-science line – you need to be aware that you’re not likely to win them over! The only time it’s worth doing this is when there are other people watching – for example, at a public debate, on an internet message board, or in a media interview. In these cases, remember that it’s the audience, not the denier, that you’re trying to win over – and so coming across well is just as important as having the right arguments.

Stay calm, confident and polite. Counter their nonsense as best you can, but don’t just be reactive – ask them which bits of the basic science they disagree with. Do they not believe CO2 is a greenhouse gas, or that the planet is warming up? Ask them what evidence they have for these extraordinary claims that contradict 150 years of science and tens of thousands of temperature measurements. If they claim it’s not a big problem, give them some real-life examples of what floods, droughts and storms are already doing to people all over the world. Professional deniers love to pick at details but often struggle when challenged on the overall picture, because their cherry-picked criticisms don’t add up to anything coherent.

Danny Chivers is a climate change researcher, activist, carbon footprint analyst and performance poet. He is author of the all-new No-Nonsense Guide to Climate Change, published by New Internationalist – a handy pocket guide to the latest climate change science, targets, solutions, politics, activism, and the way forward.

For the latest scientific debunking of contrary climate arguments, keep an eye on www.realclimate.org and www.skepticalscience.com

  1. nin.tl/gxGtbg ; nin.tl/ggpkmK and nin.tl/e1rSrU
  2. nin.tl/fTzx3y
  3. Tyndall, J (1861), ‘On the absorption and radiation of heat by gases and vapors, and on the physical connexion of radiation, absorption, and conduction’ Philosophical Transactions of the Royal Society of London, Vol 151, Part I.
  4. nin.tl/bk59Hd
  5. nin.tl/d4vx46
  6. Doran, P. T. and M. Kendall Zimmerman (2009), ‘Examining the Scientific Consensus on Climate Change’, EOS, Transactions of the American Geophysical Union 90: 22.
  7. Murphy et al (2009), ‘An observationally based energy balance for the Earth since 1950’, Journal of Geophysical Research, 114. See also www.skepticalscience.com ‘It hasn’t warmed since 1998’
  8. Domingues et al (2008) ‘Improved estimates of upper-ocean warming and multi-decadal sea-level rise’, Nature, 453.
  9. National Oceanic and Atmospheric Administration
  10. See for example Stanhill, G. and S. Cohen (2001), ‘Global dimming: a review of the evidence for a widespread and significant reduction in global radiation with discussion of its probable causes and possible agricultural consequences’, Agricultural and Forest Meteorology 107.
  11. The House of Commons Science and Technology Committee (31 March 2010), the Science Assessment Panel (14 April 2010), and the Independent Climate Change Email Review chaired by Sir Muir Russell (7 July 2010).
  12. ‘Release of global-average temperature data’, Met Office press release, 5 December 2009. nin.tl/dyuKWv
  13. Figures from UNESCO/SCOPE/UNEP Report ‘The Human Perturbation of the Climate Cycle’, available at nin.tl/bc7rhm. Gigatonnes of carbon converted into billions of tonnes of CO2 by my own calculation (multiplied by 3.67).
  14. nin.tl/9N4i5B
  15. IPCC Fourth Assessment Report, Working Group 1, Section 2.7.
  16. nin.tl/ gYpVgj
  17. nin.tl/ekctai
  18. There’s an excellent list of the positive and negative effects of climate change, with links to the relevant scientific research, at nin.tl/bBzYPb
  19. Global Humanitarian Forum (2009) The Anatomy of a Silent Crisis, available online at nin.tl/awh8nC
  20. A set of globally-agreed targets to improve health and fight poverty and hunger. See www.un.org/millenniumgoals/
  21. Global Humanitarian Forum (2009) The Anatomy of a Silent Crisis.
  22. The Noosa Journal, ‘Global warming skeptic takes his message to Noosa’, 11 January 2010. See also www.prwatch.org/node/8686
  23. Union of Concerned Scientists and Government Accountability Project, February 2007, Atmosphere of Pressure: Political Interference in Federal Climate Science.
  24. Roger Harrabin, 6 April 2007, The Today Programme, BBC Radio 4. David Wasdell, February 2007, ‘Political Corruption of the IPCC Report?’.
  25. J Vidal, ‘If Rajendra Pachauri goes, who on Earth would want to be IPCC chair?’ The Guardian, 3 September 2010.
  26. UNEP, www.grid.unep.ch/glaciers/