With conflicting ideas and statements all around, it is often difficult to separate the reality of global warming from the myths. As a guide, we’ve compiled some of the more prominent myths of global warming fuelled by sceptics and pointed out the reality.

Myth 1 - Climate change has nothing to do with humans

There is indisputable evidence from observations that the Earth is warming. Concentrations of CO2, created largely by the burning of fossil fuels, are now much higher, and increasing at a much faster rate than at any time in the last 600,000 years. CO2 is a greenhouse gas, the increased concentrations have contributed to the recent warming and probably most of the warming over the last 50 years.

The natural greenhouse gas effect keeps Earth much warmer than it would otherwise be, without it Earth would be extremely cold. Greenhouse gases such as carbon dioxide, methane, oxides of nitrogen and water vapour behave like a blanket around Earth. These gases allow the Sun's rays to reach Earth's surface but impede the heat they create from escaping back into space.

Any increases in the levels of greenhouse gases in the atmosphere mean that more heat is trapped and global temperatures increase - an effect known as 'global warming'.

Myth 2 - Temperature observations don’t support global warming

Temperatures provide the clearest evidence that the climate is changing and globally the average temperature has risen by more than 0.7 °C over the last 100 years. The rise in global surface temperature has averaged more than 0.15 °C per decade since the mid-1970s. Warming has been unprecedented in at least the last 50 years, and the 17 warmest years have all occurred in the last 20 years. This does not mean that next year will necessarily be warmer than last year, but the long-term trend is for rising temperatures.

Myth 3 - The current climate change is just part of a natural cycle

Earth's climate is complex and influenced by many things, particularly changes in the Earth’s orbit, volcanic eruptions, and changes in the energy emitted from the Sun. It is well known that the world has experienced warm or cold periods in the past without any interference from humans. The ice ages are good examples of global changes to the climate, and warm periods have seen grapes grown across much of Britain. Something that is happening again now.

Over the several hundred thousand years covered by the ice core record, the temperature changes were primarily driven by changes in the Earth's orbit around the Sun. Over this period, changes in temperature did drive changes in carbon dioxide (CO2). Since the Industrial Revolution  and specifically over the last 100 years, CO2 and CO2 equivalent concentrations (gases such as methane) have increased by 30% due to human-induced emissions from fossil fuels and increased reliance on cattle farming.

Ultimately, temperature and CO2 concentrations are linked. In recent ice ages, natural changes in the climate, such as those due to orbit changes, led to cooling of the climate system. This caused a fall in CO2 concentrations which weakened the greenhouse effect and amplified the cooling. Now the link between temperature and CO2 is working in the opposite direction. Human-induced increases in CO2 are driving the greenhouse effect and amplifying the recent warming.

Myth 4 - It’s all to do with sun spots, not carbon dioxide

There are many factors which may contribute to climate change. Only when all of these factors are included do we get a satisfactory explanation of the magnitude and patterns of climate change over the last century.

Over the last 1,000 years most of the variability can largely be explained by cooling due to major volcanic eruptions and changes in solar heating.

In the 20th century the situation becomes more complicated. There is some evidence that increases in solar heating may have led to some warming early in the 20th century, but direct satellite measurements show no appreciable change in solar heating over the last three decades. Three major volcanic eruptions in 1963, 1982 and 1991 led to short periods of cooling. Throughout the century, CO2 increased steadily and has been shown to be responsible for most of the warming in the second half of the century.

As well as producing CO2, burning fossil fuels also produces small particles called aerosols which cool the climate by reflecting sunlight back into space. These have increased steadily in concentration over the 20th century, which has probably offset some of the warming we have seen.

Changes in solar activity do affect global temperatures, but research shows that, over the last 50 years, increased greenhouse gas concentrations have a much greater effect than changes in the Sun's energy.

Myth 5 - Climate change computer models are unreliable

There have been major advances in the development and use of models over the last 20 years and the current models give us a reliable guide to the direction of future climate change.

Computer models cannot predict the future exactly, due to the large number of uncertainties involved. The models are based mainly on the laws of physics, but also empirical techniques which use, for example, studies of detailed processes involved in cloud formation. The most sophisticated computer models simulate the entire climate system. As well as linking the atmosphere and ocean, they also capture the interactions between the various elements, such as cryosphere (ice) and geosphere (land).

Climate models successfully reproduce the main features of the current climate (e.g. rainfall in the map below), the temperature changes over the last 100 years, the Holocene (6,000 years ago) and Last Glacial Maximum (21,000 years ago).  This data is captured from deep ice cores and oceanic sediments.

Current models enable us to attribute the causes of past climate change, and predict the main features of the future climate, with a high degree of confidence. We now need to develop the models to provide more regional detail of the impacts of climate change, and a more complete analysis of extreme events.

Myth 6 - Why bother trying to do anything about climate change.  It's too late anyway.

If we continue emitting greenhouse gases this warming will continue and delaying action will make the problem more difficult to fix.

The global average temperature will increase by 2 to 3 °C this century – according to the Intergovernmental Panel on Climate Change’s (IPCC) mid-range estimates (blue line on the graph below). This rise in temperature means that the Earth will experience a greater climate change than it has for at least 10,000 years and it would be difficult for many people and ecosystems to adapt to this rapid change. This level of change is undocumented in all human history. It calls on all of us to act now. If we stopped emitting tomorrow we could expect increasing temperatures to 2050. However, with action now and in the next 10 years, there is still time to ensure that from 2050, the temperatures and effects that come with it will begin to stabilize.

These temperature increases are likely to result in an increased frequency and severity of weather events such as heatwaves, storms and flooding. Rising levels of greenhouse gases in the atmosphere could set in motion large-scale changes in Earth’s natural systems. Some of these could be irreversible — the melting of large ice sheets will result in major consequences for low-lying areas throughout the world.

UK Government have committed to a Climate Change Act (2008). The forst of its kind ion the world. This has set demanding targets to rediuce CO2 emisions by 34% from 1990 levels by 2020 and by 80% by 2050. This will take a gargantual effort from all of us but the technology that will be required in terms of renewable energy (wind turbines, wave power, tidal power – araes where the Uk are not only world leaders but in the case of wind resource, the UK is the best placed nation in Europe to exploit wind resources) to deliver this change has the potential  drive the UK and much of the world out of recession.

So what is likely to happen?

A 2 degree increase above pre industrial levels of CO2 will still have serious impacts for the UK and the rest of the world. Even a 1 degree rise could see 18-60 million additional people at risk of hunger and 1,600 million additional people (1/4 of the current global population) suffering water stress. The implications of this in terms of migration displacement are collossal. The full implications of temperature changes over 3% are difficult to predict. We are in a situation now where we have a limited period where we can make a difference…

After all this, what if I still don’t believe in Climate Change?

Even disregarding all the arguments made above, the reality is that the earth’s resources are finite, not endless. Human ingenuity continues to find methods to extract more oil from more inhospitable regions and sources, to extract more metals and minerals from less bountiful locations. Ultimately, it is accepted by all the world’s oil companies that if we have not passed peak oil, we are very close to it. This means that we will be withdrawing oil from a resource that will start to yield less and less with each pumping at a time when global populations will require more and more. Without investment now in renewable alternative energy sources, we may soon come to a point where blackouts and fuel rationing become commonplace. In the same way that recycling has become commonplace and accepted over the past 30 years, resource and energy use needs to become accepted as the top of everyone’s agenda. However, we don’t have the luxury for discussing this for 30 years.

Tipping Point Ahead?

The way we have been calculating the future impacts of climate change is changing to include a missing piece of the picture. It seems we are now closer to a so-called "tipping point" in the world's climate system; this is the point after which truly catastrophic changes become beyond mankind's control and make the need for change urgent, NOW.

Change is coming; social change on a massive, unprecedented scale. There are a number of potential avenues through which this change will manifest.

In the best case scenario, we ourselves will be the architects of this change, working collectively and creatively to reshape social structures and ways of life from the bottom up to build a new paradigm based on equity and sustainability, and the kind of lifestyles that can still afford us a high quality of life and the opportunities for joy and prosperity that our own generation has enjoyed – albeit with much lower levels of material consumption.

The following link called 'wake up freak out' attempts to illustrate this, please see link in additional websites below.

Date Updated: 03/02/11