Global warming
Global warming is happening
Flooding in the UK
The question now is not whether global warming is happening but how we can curb it and if this is going to be soon enough. Whether you subscribe to a sustainable approach to life (which seems a very logical approach to me), or not, global warming is here now and needs to be dealt with now.
But why does it all happen? Well the sun heats the earth and at some point this heat is reflected back from the earth and radiated back out into space (otherwise the earth would just get hotter and hotter al the time). Certain gases like methane and carbon dioxide reflect the heat back to the earth again, reducing the amount that is radiated back into space. This is very important or the world would be a colder place. The concentration of these gases in the atmosphere is closely linked to global temperatures.
Fossil fuels are atmospheric C02 which was trapped by ancient plants. At the time these plants were alive the C02 levels were much higher and it is mainly because of the trapping and storage of this C02 as fossil fuels that the C02 levels and temperatures are as low as they are today. But since the industrial revolution we have been burning these fossil fuel C02 stores at an alarming rate.
This has led to an increase in global C02 levels over the past century that has resulted in a global temperature increase of around half a degree (we are in a warm spell at the momement anyway - this half a degree is the portion of the temperature increase that is due to human activity). Half a degree may not sound that much but we are already experiencing the censequences: icecaps are retreating, sea levels have been rising for a long time now (sea levels rise because of the extra water from melting ice, but also because as the seas warm up the water expands), altered growing seasons in the UK, unusually high rainfall (with flooding as a result), and warmer summers. This is only likely to get worse.
The Intergovernmental Panel on Climate Change (IPCC) report contains a prediction for the global temperature increase by 2100 if we just carry on as normal (this is the "business as usual" model). The prediction is an increase of around four degrees. This is likely to severely effect global weather conditions. Reduced rainfall in already arid or desert regions would have disasterous effects, and disruption of ocean currects would effect weather conditions greatly, especially here in the UK where our mild climate is dependant on the Gulf Stream.
To slow global warming there are a variety of strategies that we need to be adopting:
1 - Increased efficiency = use less. We can reducing our energy consumption by doing things like insulating our houses, using public transport more, using energy eficient lightbulbs, etc.
2 - Change in fuel type = use none. We can reduce our consumption and reliance on fossil fuels (and thereby reduce C02 emissions) by shifting to renewable sources of energy. These sources include solar, wind, hydrogen, hydro-electric energy, as well as biofuels (although use of crops grown specifically for use as a biolfuel has other potentially detrimental concequences.).
3 - Trap the C02 again. We can recover the C02 that we emit and store it up again. This is already being done in coal fired power stations. Oil and gas companies already replace the oil or gas that they pump out of the ground with C02 (which also helps push the oil and gas out making it easier to harvest).
Here are the C02 emissions per kWh for various fuel types.
You can see that changing fuel type (ie using wood for heating) can potentially reduce your C02 emissions.
Some strange sounding solutions
It has also been suggested that by promoting algal growth in the sea that we could reduce C02 levels. Plankton traps more C02 that anything else on earth including the rainforests and if it wasn't doing it as you read this then global C02 levels would be much higher. So the idea is that the algae traps the C02 from the air, dies, some of it sinks to the sea bed where it enters the slow process of becoming a fossil fuel again. The problem with this method is that there is not enough iron in the seas (algae needs iron to grow). Experiments which added extra iron to the sea have shown that so much would need to be added that it would defeat the object.
Some other people have suggested large floating silver balloons to reflect the suns rays as well as mirrors launched into space - both these 'solutions' could be argued to be missing the point because so much energy would be needed to implement them.
Political approaches to the problem
Bottom up approach - there is a growing tide of opinion behind the effort to reduce global warming. By individually doing something about it we will an have an accumulative effect. At the same time politicians see that global warming is something which will win votes.
Top down approach - at the end of the day we need top down approaches if we are going to effectively halt altmospheric C02 increase, however much we try and help on an individual basis. Seat belt laws were passed as they were considered to be in the best interests of the people and reducing global warming is surely also in the people's best interest? Legislations to increase efficiency are already in place as well as C02 reduction targets in the UK and across Europe, but at the moment it is still too little, too late. No doubt the politicians are worried about a global reccession but surely this is the ineviatable consequence of a reduction in consumption (assuming some breakthrough in renewable technology is not made) but still preferrable to extreme global warming?
Obviously we need to adopt bottom up and top down approaches if we are to succeed.
