Global Warming and Climate Change
The Earth's climate is complex with many factors influencing it.
Nevertheless, there is a clear and ever-growing body of evidence showing that:
- The world is warming
- This warming is due to human activity increasing levels of greenhouse gases in the atmosphere
- If emissions continue unabated then the global warming will continue as well, bringing with it increasingly serious consequences
Considered by many to be the most authoritative source on global warming and climate change, the Intergovernmental Panel on Climate Change (IPCC) issued its Fourth Assessment Report in February 2007. In the report the IPCC stated "Warming of the climate system is unequivocal" and that "Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide [three of the main greenhouse gases that cause global warming] have increased markedly as a result of human activities since 1750 and now far exceed pre-industrial values".
One of the conclusions of the report is that by the end of the 21st century temperatures may rise by between 1.8 and 4 deg C (best estimates) or 1.1 and 6.4 deg C (including all uncertainties).
Included in the IPCC report was the following graphic:
The main graph shows the rise in carbon dioxide levels over the past 10,000 years. The inset graph illustrates the increase in carbon dioxide since 1750, when the level was around 275 parts per million (ppm) as compared to the present day concentration of over 380 ppm.
Climate Change - What Could Happen
It is not known for certain what effects climate change will bring, but there will be consequences.
The world's habitats and ecosystems depend on a delicate balance of rainfall, temperature, and soil type. A rapid change in climate could upset this balance and seriously endanger many living species.
Most past climate changes occurred slowly, allowing plants and animals to adapt to the new environment or move somewhere else over generations. However, if future climate changes occur as rapidly as scientists predict, plants and animals may not be able to react quickly enough to survive. In fact the change in climate may reverse much of the conservation work that has been advancing in recent years.
For example, Arctic sea-ice is shrinking (see below) and the earlier annual break-up of sea-ice is cutting short the spring hunting season for polar bears, which rely on floating banks of ice to reach their prey and, in trying to swim the greater distances, many are drowning. The disappearance of the sea ice in summer months is forcing the hungry bears to spend longer on land, giving a false impression that numbers are increasing.
Latest estimates indicate a decline in Arctic sea ice area of about 8 per cent in the last decade alone (The UK Climate Change Programme Mar 2006 ©Crown Copyright 2006)
Some of the changes that are predicted are:
- hot extremes, heat waves and droughts will become more frequent
- heavy precipitation events, storms, hurricanes and flooding will become more frequent
- sea levels will rise and there will be significant loss of land
- weather patterns will change
- thousands of animal species and plants will die and become extinct
- billions of people will run out of water
- food shortages will occur
- food and water scarcity will cause civil unrest
- political tensions over resources will increase the chance of conflict
Despite the stability and economic growth that many of us have enjoyed throughout our lives, the world as we know it looks set to change forever.
What do we need to do?
Sustainability
Sustainability is about human impact on the environment; from the way we use natural resources such as water, coal, trees and gas, through to how we manage the waste from the production and consumption of goods. The aim is to lessen our 'footprint' on the Earth so that, whilst living our lives in a way that fulfils our needs, we also leave our world in good shape for generations to come.
There are 6 R's related to sustainability:
Re-Think:
We should re-think our current lifestyles and question whether we can continue to live the way we do now in terms of energy use and products we buy.
Re-Use:
Many products are so plentiful we throw them away without any thought after
using them. Re-using products or parts of products can often use less energy
than recycling them.
Recycle:
Recycling can help prevent environmental damage by minimising the amount of
material and energy used during production and processing by taking existing
product waste and re-processing the material for use in new products.
Repair:
We should choose products that can be repaired when a part breaks and not
simply the whole product thrown away and then a replacement purchased.
Reduce:
Manufacturers should look at reducing the amount of material and energy used
during a product's life cycle.
Refuse:
We should consider refusing to buy or use certain products. Food is said to be
the largest single factor affecting our eco-footprint. Packaging, processing
and transport use huge amounts of energy and the discarded packaging creates
massive waste.
In summary
- The temperature of the Earth is largely controlled by the presence of greenhouse gases in the atmosphere
- Carbon dioxide is by far the largest greenhouse gas
- There is a fine balance of carbon dioxide emission and absorption that keeps the temperature of the Earth at a level suitable for most animal and plant species
- Since the industrial revolution, man has been devouring the Earth's resources at an unsustainable rate and burning fossil fuels to meet our energy needs and our requirement for manufactured goods
- This has caused a substantial increase in carbon dioxide emissions
- Carbon dioxide acts as a blanket trapping more of the Sun's heat in the atmosphere
- This causes global warming
- This creates climate change
- Billions of people will now be affected and unless we act now to control our carbon emissions there will be disastrous results
- There is only one answer
- Taking a sustainable approach and REDUCING CARBON
- WE MUST TAKE ACTION NOW