Debating Climate Change

The world will no longer be divided by the ideologies of ‘left’ and ‘right’ but by those who accept ecological limits and those who don’t.

Wolfgang Sachs, Wuppertal Institute

The concept of climate change was first raised in scientific circles in the late 1800s. In recent decades climate change has been the subject of an international debate among scientists, politicians, environmental activists and the public. The focus of debate has included the causes of global warming, evidence to support climate change theories, the accuracy of future projections and the actions that should be taken.

A number of arguments for and against action on climate change are outlined under the following sub-headings:

  • Climate change – fact or fiction?
  • Is climate change a priority?
  • Is global warming caused by human actions?
  • Who should we to listen to?
  • Are future projections accurate?
  • Is preventative action a priority?

Climate change - fact or fiction?


There is consensus among the world’s top scientists that global warming is happening. The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the assessment of climate change. Scientists from over 190 countries contribute to the work of the IPCC. This statement from the IPCC’s assessment report in 2007 is accepted as confirmation that climate change is real, and cannot be denied on scientific grounds:

Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level.



There are those who believe that climate change is a conspiracy and that politicians and scientists are exaggerating the consequences of global warming and climate change to create fear among the public and greater publicity and funding for themselves.

Scientists who want to attract attention to themselves, who want to attract great funding to themselves, have to [find a] way to scare the public…and this you can achieve only by making things bigger and more dangerous than they really are.

Petr Chylek, Professor of Physics and Atmospheric Science, Dalhousie University

Is climate change a priority?


The increasing number of climate related disasters and the rate at which global temperatures are rising is a growing concern. In the last 100 years the earth’s global surface temperature has risen by an average of 0.74°C. The IPCC predict that global temperatures could rise by between 1.1°C and 6.4°C by 2100 – that’s more than double, and possibly over eight times, the increase in the last century.

According to the UNDP 326 climate-related disasters, affecting over 262 million people occurred each year between 2000 and 2004. If global warming were to reach the temperatures predicted by the IPCC between now and 2100, the number of climate-related disasters, and people affected, would rise considerably.

Future climate change is expected to put almost 50 million people at risk of hunger by 2020. Shrinking freshwater supplies for drinking as well as agriculture will affect billions of people.



There is an argument that calls for current humanitarian issues (poverty, human rights, HIV and AIDS, etc.) to be addressed as a higher priority ahead of climate change.

Everyday 30,000 people on this planet die of the diseases of poverty… a third of the planet doesn’t have electricity. We have a billion people with no clean water. We have half a billion people going to bed hungry every night. Do we care about this? It seems that we don’t. It seems that we would rather look a hundred years into the future than pay attention to what’s going on now. I think that’s unacceptable. I think that’s really a disgrace.

Michael Crichton, Novelist

Is global warming caused by human actions?


Human activities do contribute substantially to climate change. Scientific data published by the IPCC, and other official bodies, shows significant rises in greenhouse gas (GHG) concentrations and global temperatures since the beginning of the industrial era. There is an argument that GHG emission increases are above those that would be expected from natural causes.

Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations. It is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antartica).

Global GHG emissions due to human activities have grown since pre-industrial times, with an increase of 70% between 1970 and 2004.



There are some who believe that human activity is not contributing significantly to climate change. They argue that natural factors are the cause of the increase in greenhouse gas concentrations in the atmosphere and that climate change is part of the earth’s natural cycle. The earth has a history of temperature changing cycles, and there are some who believe that the global warming we are experiencing is part of that natural cycle.

The small (+0.7 deg C) increase in the average global temperature over the last hundred years is entirely consistent with well-established, long-term, natural climate trends.

Jim McConalogue, The European Journal

It is no secret that increased solar irradiance warms Earth’s oceans, which then triggers the emission of large amounts of carbon dioxide into the atmosphere. So the common view that man’s industrial activity is a deciding factor in global warming has emerged from a misinterpretation of cause and effect relations.

Dr Habibullo Abdussamatov, Head of Space Research, Pulkovo Observatory

Who should we listen to?


Many leading climate change sceptics do not have a background in science. There is an argument that their lack of scientific experience undermines the issues they raise in the climate change debate. It has also been pointed out that sceptics gain support for their campaigns using media directed towards the public rather than through scientific or academic forums. Official supporters of climate change (IPCC, UNDP, academic research reports, etc.) publish their findings in formal journals and reports that are mainly read by academics and other scientists. As a result the public are left with an unbalanced overview of the climate change debate and often believe that there is more support for the sceptics than is the actual case. It is difficult for members of the public to access the scientific arguments supporting climate change.

A larger group of economists, political scientists and intellectuals… remain unconvinced. This community are strong on economics but they are not scientists and rarely understand the reliability (and limitations) of experimental measurements – another fact that is rarely highlighted in the media.

Cormac O’Raifeartaigh


Climate change sceptics draw attention to the vague language used in scientific reports. They also claim climate change scientists manipulate data to form conclusions that will support climate change theories.

There is no scientific consensus on how much the world has warmed or will warm; how much of the warming is natural; how much impact greenhouse gases have had or will have on temperature; how sea level, storms, droughts, floods, flora, and fauna will respond to warmer temperature; what mitigative steps – if any – we should take; whether (if at all) such steps would have sufficient (or any) climatic effect; or even whether we should take any steps at all.

Christopher Monkton

Are future projections accurate?


Climate change projections are based on long-term averages and conservative models. A broad range of data, over a long time period is analysed. This allows scientists to identify trends and averages and project these results into future timescales. There are a number of scientists who believe that the parameters chosen in climate change models may be too conservative and underestimate the magnitude of future global warming. They believe the situation is going to be even worse than expected.


There are some who claim that climate change analysis is inaccurate. The measurement tools and models used for analysis are questioned. Some argue that there is too much dependence on information from weather stations as changes in their surroundings can affect the data and lead to incorrect readings. Some sceptics argue that there are too many variable factors involved in computer modelling to effectively monitor global climate patterns and predict future events.

Is preventative action a priority?


There are claims that the climate change debate is over and it’s time now for action to reduce greenhouse gas emissions. It is argued that whether or not the future projections of climate change are absolutely accurate, the fact that climate change has been shown to have a negative effect on humanity and the environment, and is predicted to become an even greater problem, is reason enough to act now. Many believe that to ignore climate change and write off estimated projections would be an unfair, immoral and a short- sighted gamble when there is so much at risk.


Climate change has already begun and greenhouse gases that are already in the atmosphere will remain there for decades, or longer. It is argued that human intervention at this stage will neither worsen nor improve the situation, as a portion of the warming associated with past human activity has not yet been realised. It is also argued that many societies depend on fossil fuels and it is not feasible to alter this dependence without dramatic changes to current social and economic structures.

To find out more:

These arguments lay out some of the main issues raised in the climate change debate. Whether or not there is a clear ‘winner’, this debate allows people to make an informed choice about climate change and assess each of the arguments for themselves. To read more about the issues outlined in this section here are some useful links: