New Internationalist books and publications

World Development book case study: Climate Sceptics

Is climate change really happening?

The Great Green Con no. 1

The hard proof that finally shows global warming forecasts that are costing you billions were WRONG all along.  

The Mail on Sunday today presents irrefutable evidence that official predictions of global climate warming have been catastrophically flawed.
The graph on this page blows apart the ‘scientific basis’ for Britain reshaping its entire economy and spending billions in taxes and subsidies in order to cut emissions of greenhouse gases. These moves have already added £100 a year to household energy bills.
The graph shows in incontrovertible detail how the speed of global warming has been massively overestimated. Yet those forecasts have had a ruinous impact on the bills we pay, from heating to car fuel to huge sums paid by councils to reduce carbon emissions. The eco-debate was, in effect, hijacked by false data. The forecasts have also forced jobs abroad as manufacturers relocate to places with no emissions targets.

Daily Mail March 16th 2013

Anybody who has any interest in issues affecting world development will take a keen interest in arguments about climate change. The majority of climate scientists have supported the view that climate change is a man made process that is causing complex changes to the earth’s atmosphere resulting in a global rise in temperature. There have always been climate sceptics who have argued that this is not true and their views have been promoted by the fossil fuel industry and other groups who claim that climate change is a myth that is harming global economic progress. That view received unexpected support from global temperature statistics released by several climate research institutions including the UK Met Office and the Climate Research Department of the University of East Anglia. They show that average surface temperatures have hardly risen (+0.1o C) over the last decade. Carbon emissions have continued to rise and the mismatch between increased global greenhouse gas emissions and stable temperatures has made the debate over the existence of man made climate change even more heated. Climate change deniers have been quick to take the opportunity to attack the climate warming lobby as misguided and misinformed.

According to Met Office predictions, the pause in temperature increases will last to at least 2017 and global surface temperatures will fall below even the lowest temperature increases predicted by climate change models. Does this mean that climate change predictions are all wrong and the skeptics were right all along? The IPCC’s Fifth Assessment Report (published September 30th 2013) year admits that there has been no statistically significant surface temperature increase since January 1997. Climate change skeptics claim that this is conclusive evidence that the threat of global warming has been exaggerated by environmentalists driven by the desire to justify new eco-taxes, get more money and guarantee more work for themselves. On the other hand, over 800 scientists who contribute to the work of the IPCC are more convinced than ever that global climate change represents a major threat to man. How can people reach such different conclusions when they have access to the same evidence? There is no doubt that the complexity of the global climate mechanism makes scientific investigation very difficult.

Where do you start?

Different models

One of the major reasons for the discrepancy in views is the use of different models to predict what is likely to happen in the future. The model used by the IPCC and other research centres is a GCM (Global Circulation Model). This type of model divides the earth and its atmosphere into a grid system and uses mathematics to imitate the climate system and all the multiple factors that may have an impact on climate in each of the grids. The complexity of the climate system means that there are thousands of equations used to try and imitate the climate process and predict climate change. The strength of the models is the detailed information that is included in setting up the model. The weakness is the sensitivity the model has to the accuracy of the information about the processes and feedbacks and its inability to respond to what is actually happening to surface temperatures.

The IPCC research has mostly been based on models that use a type of GCM and their predictions of the range of surface temperature increases in their Fourth Assessment Report (2007) suggested that doubling the carbon concentrations in the atmosphere would mean that “the equilibrium climate sensitivity…is likely to be in the range 2°C to 4.5°C with a best estimate of about 3°C and is very unlikely to be less than 1.5°C. Values higher than 4.5°C cannot be excluded.” The implications of a rise of 3°C are profound and the figure was widely used to urge governments to act to reduce carbon emissions. The Fifth Assessment Report does slightly alter that key figure from the earlier study. The temperature range given for a doubling of CO2 in the atmosphere has been changed to 1.5C to 4.5C which scientists say reflects improved understanding, better temperature records and new estimates for the factors driving up temperatures.

Another type of model widely used by climate scientists to predict future climate change is the energy balance model. This type of model of the earth’s climate system does not use complex equations. The earth is treated as a whole or sometimes two hemispheres. Only a few factors are considered such as changes in greenhouse gases, volcanic aerosols and data on global temperatures. The weakness of this model is that it does not imitate the complexity of the climate but it does use current temperature data to estimate the sensitivity of the climate system. The model responds to actual climate observations. The results posted by research groups using the energy balance model generally predict lower climate sensitivity to increased greenhouse gases than GCMs. A Norwegian government funded team predicted a range of temperature rise of 1.2-2.9°C with a most likely increase of 1.9°C. Other studies have published similar results. Only long term comparison of results from the different types of models will reveal which is the more accurate. However both models predict a rise in global temperatures that will have a huge impact on life on earth.

How sensitive is the earth’s climate to increased CO2?

Global greenhouse gas emissions are still rising and determining the sensitivity of the climate to increased greenhouse house gases in the atmosphere is at the heart of the climate change debate. The issue deserves much more examination than this short case study and there is a huge amount of written material available. Individual climatic influences and feedback loops can amplify and sometimes moderate climate change. One of the most complex and contentious is the impact of clouds. The amount of cloud cover that we experience is partly a function of atmospheric temperature which makes predicting the amount and type of cloud cover that will occur in the future hugely important but very difficult. In all models clouds are assumed to increase global warming but in its most recent report the IPCC state that “the cloud feedback remains the most uncertain radiative feedback in climate models.” Some types of cloud may actually reduce warming and if that is the case, increasing cloud may be a partial explanation for a slowing down of the rise in surface temperatures.

Clouds and aerosols are the single largest source of uncertainty in simulating the climate change of the next 50 to 100 years. Models have a hard time simulating clouds and it is not well understood how clouds interact with human-produced aerosols such as pollution haze.
Chris Bretherton - Lead author IPCC Fifth Report

Another major factor that makes climate change prediction so difficult is the impact of the oceans. Only 1% of the increased heat trapped by our increased carbon missions goes into warming the atmosphere. The vast majority (93%) is absorbed by the oceans. The rest goes into heating the land and melting polar ice. The oceans have an enormous heat capacity and some scientists believe that they have already absorbed extra energy as a result of climate change and potentially helped to mask the impact of increased carbon emissions.

We don’t yet know exactly how much the climate will warm from the CO2 already in the air. There is a delay of several decades between forcing and final response. Until an equilibrium temperature is reached, present day observations will not tell us the exact value of the climate’s sensitivity to CO2.

The reason for this is primarily the large heat capacity of the oceans. The enhanced greenhouse effect from higher CO2 levels is indeed trapping energy in the climate system according to expectations, but the enormous quantity of water on earth is absorbing most of the resulting heat. Due to water’s high heat capacity, this absorbed energy shows up as only a modest ocean warming, which in turn dampens the temperature change on land and lowers the global average trend.

This is commonly referred to as the climate system’s thermal inertia. According to model experiments and consistent with data from past climate changes, this inertia results in a lag of several decades between the imposition of a radiative forcing and a final equilibrium temperature.
Coby Beck –

Periodic changes in ocean currents could also be a factor. El Nino is a naturally occurring phenomenon characterised by complex changes in global ocean currents. During an El Nino period heat is pumped from the oceans into the air increasing average global temperatures. The counterpart of El Nino, La Nina, has a cooling effect and has been dominant over El Nino for eight of the past fifteen years. El Nino has been the stronger factor for only two of those fifteen years. Many scientists believe that factors such as the decline in El Nino, and a decline in the solar cycle since its peak in 2002, explain why there has been a pause in the global temperature rise during the last seventeen years. That is why it is so important to consider temperature fluctuations over a longer time scale.

Just a quick look at some of the factors that may influence climate makes it clear why accurate predictions are so difficult. However the overwhelming majority of scientists involved in climate research support the view that climate change is happening and the cause is human activity. The Fifth IPCC Report concludes that it is ‘95% certain’ that there is a link between climate change and human activity.

The IPPC concludes there is a 50-50 chance that global temperatures will exceed 4C this century if carbon emissions are not curbed. Such a rise would have catastrophic consequences. So if you are still feeling confused about all this complex science, it all boils down to this: how lucky do you feel?
Damian Carrington - Environment Blog The Guardian 27th September 2013

Arguing with climate sceptics about the future of the global climate could just be another interesting discussion about science if the consequences were not so serious. Sea level has risen by 20cms in the last hundred years and if nothing is done to reverse the current trends in emissions that increases to 45-82 cms by the end of the century. The impacts on many countries will be catastrophic. Why do individuals and governments find it so difficult to react to such grave warnings and take action to ameliorate climate change impacts? The answer probably lies in an area of even more complexity than global climate – human nature and behaviour.

A University of British Columbia study of American attitudes toward climate change over two decades (Journal of Climate Change Feb 2013) found that local weather, particularly temperature, is a major influence on public and media opinions on the reality of global warming.

Our study demonstrates just how much local weather can influence people's opinions on global warming. We find that, unfortunately, a cold winter is enough to make some people, including many newspaper editors and opinion leaders, doubt the overwhelming scientific consensus on the issue.
Prof Graham Donner University of British Columbia

If an opinion poll had asked the British public in June 2013 about the danger posed by climate change they would almost certainly have rated the risk as quite low. A cold winter was followed by the coldest Spring for 50 years. During an Oxford Farming Conference, Stuart Agnew (UKIP MEP) cited the fact that much of his sugar beet crop was frozen in the ground as ‘evidence’ of the lack of global warming. By the middle of July temperatures had reached 30 degrees and climate change was a reality again.

In September 2013 Australia voted for Tony Abbot as their new Prime Minister. His views on climate change are very clear – he has called predictions of increased temperatures ‘absolute crap’. His first actions as Prime Minister were to disband the Climate Change Commission and repeal carbon tax legislation aimed at reducing greenhouse gas emissions in Australia. He believes that the carbon tax has a negative impact on the Australian economy and will save households $550 a year. On October 20th a state of emergency was declared in New South Wales because of record bush fires that threatened huge areas of the state. The bush fires were caused by unusually high temperatures and high winds and highlighted the vulnerability of Australia to future climate change. It is obviously impossible to predict whether the election result might have been a little different if the election had been held two months later.

The worst thing you can do when you try to win an argument is to stereotype the opposition. However, it is no surprise that probably the most famous climate change deniers in this country are Nigel Lawson (former Conservative Chancellor of the Exchequer) and the Daily Mail!

People who are scep­tical about cli­mate change are likely to be older, male and polit­ic­ally con­ser­vative.
The Politicization of Climate Change- McCright & Dunlap, 2011

More than half of the incoming Republican politicians in the 2010 mid-term elections in the United States dispute climate change. Republicans are pro-business and anti-government. They are ideologically opposed to anything that adds ‘unnecessary’ costs to business because it slows economic progress. Big business in the form of fossil fuel companies and others, funds groups which are opposed to climate change and has created an alternative science forum which aims to discredit the research of the IPCC and any other scientific research that supports the notion of climate change. Newspapers and television channels are often funded by powerful business concerns (particularly in the United States) and support the views of climate change sceptics. It is not difficult to find an outlet for your views if you are a climate change denier. Climate deniers are a very powerful group.

Even if we accept that there are many people who are unconvinced that climate change is occurring, the rational approach would appear to be to adopt the precautionary principle and accept that even though the science on climate change may not be totally convincing, ignoring the possible catastrophic consequences would be absolutely stupid. Taking measures to mitigate the potential damage by reducing emissions now is the logical first step. We could develop new technologies, tax emissions and educate society to change its behaviour. As the elections in Australia have proved, it is not as simple as that.

Where does the argument go next? The current IPCC report has gathered together the current scientific research on climate change and reported its conclusions. The next IPCC reports are about the impacts of climate change (March 2014) and mitigation of climate change (April 2014). A synthesis of the three reports is due in October 2014. The reports might clarify some of the issues surrounding climate change but getting individuals and groups of countries to respond will not be easy.

Further Reading

There is so much available online and in print about this issue. I am assuming that if you are interested in development you are rational and convinced by the scientific case for climate change being caused by human activity! This is just a few of the items available online;

The Daily Mail article claiming that the evidence shows that climate change is not happening. May 2013
The Great Green Con no. 1

Daily Telegraph article commenting on the same evidence May2013
Hay Festival 2013: global warming is ‘fairly flat’, admits Lord Stern

Guardian article by Dana Nuccitelli and John Abraham explaining the apparent stalling in temperature rise June 2013
More pieces of the global warming puzzle assembled by recent research

New York Times article by Justin Gillis explaining the apparent stalling in temperature rise June 2013
What to Make of a Warming Plateau

Reuters article - Climate scientists struggle to explain warming slowdown – Alister Doyle April 2013
Climate scientists struggle to explain warming slowdown

Article from Scientific American Alex Kirby May 2013
Is Global Warming Cooler than Expected?

Article by David Appell in Yale Climate Forum
W[h]ither Global Warming? Has It Slowed Down?

Article in BBC News by Matt McGrath discussing meeting of climate experts to discuss unusual weather patterns in UK June 2013
Met Office experts meet to analyse ‘unusual’ weather patterns

The Politicization of Climate Change - McCright, A.M. & Dunlap, R.E. (2011). Cool dudes: The denial of cli­mate change among con­ser­vative white males in the United States. Global Environmental Change 21 (4) 1163–1172.
Available online

Advice on how to talk to climate sceptics!
Responses to the m ost common skeptical arguments on global warming