The cause of global warming – the mechanics of Earth as a greenhouse
The Earth presently retains more warmth from the sun, about 0.85W per square metre, than it radiates back into space.
CO2, methane, nitrous oxide and water vapour in the atmosphere slow down this radiation.
Methane is the most potent greenhouse gas, trapping most warmth. But it degrades to half its strength in a mere 7 years.
CO2 is the main culprit as it takes about 100,000 years for 63% of this gas to be removed from the atmosphere by natural processes.
Water vapour levels are constant but the other gasses are not, due to human activity. CO2 is rising steeply because of the burning of
,notably coal and oil products.
Forests store carbon from the air through photosynthesis. But as humans have cleared about half of the Earth's forests and continue to do so further at a rapid rate, you get the picture...
The Intergovernmental Panel on Climate Change predicts a rise in global temperature by about 5C by the end of this century. Others predict less, some up to 8C. That will have severe
health effects of global warming.
And as an "aside"…
"Global dimming" of the sun’s potency is caused by human-made aerosols in the air. Some aerosols cause ozone-layer depletion. The ozone layer protects us from harmful ultra violet radiation. So when we tackle aerosol pollution global warming will be more intensely felt.
The frying pan or the fire? Mmmmm…
Of course Al Gore has convinced many people with An Inconvenient Truth, but if he cannot quite convince you yet then view
Cause of global warming - What we do
Research shows that the start of the present global warming phenomenon coincides with the Industrial Revolution. Over the last 45 years in particular CO2 has risen particularly fast, much faster than possible in any natural cycle.
Human activity, burning fossil fuel and deforestation therefore definitely contributes to global warming.
The Industrial Revolution is a period between about 1700 and 1900 when great mechanical and technological advances were made, starting in the United Kingdom.
It brought much material progress. But already by the middle of the 19th century the river Thames was a sewer and human health in cities was affected by smog and by unhealthy work practices.
The phenomenal explosion of hi-tech, bio-chemical and bio-tech industries that produce the tsunami of machines, appliances gadgets and games that are part of your life started with the Industrial Revolution.
Why… even the computer that you are now reading this on was first conceived by Charles Babbage who died in 1871!
The already obvious social and environmental costs of widespread industrialisation of that time, did not stop the export of this new culture, that of consumerism, all over the world.
Consumerism is about buying and "consuming" as much as possible in the shortest possible time, using the Earth’s resources as if there was no tomorrow. This is what the idea of "progress" has come to.
Global warming is one of its products.
Cause of global warming - Our beliefs and values
Why do we act like this?
It’s the way we think about ourselves and the world.
Present-day beliefs and values are still very much based on those of the Enlightenment, beginning in the 16th century. It started our belief in progress through accumulation of material things and the over-emphasis on the individual rather than the common good.
Philosopher Rene Descartes is one of its founding fathers. He is the man of the famous quote: "I think, therefore I am"! I saw an advertisement recently that encapsulates what it has become in our age: "I shop, therefore I am"!
This thinking recognises no limits, allowing exploitation for the interchangeable goals of human progress and individual profit.
A great part of our finite energy sources is expended on throw-away consumer goods with a deliberate limited life-span. This means that the "ecological footprint" of global human society is already about 25% more than the Earth can sustain while daily tonnes of greenhouse gas are pumped into the atmosphere.
Our attitudes therefore are a big cause of global warming.
Now we know that all "things" are interconnected and interdependent in a great web of life. Pull one strand and the whole web is affected.
Perhaps we’re now beginning to act on this wisdom, but we must hurry.
Cause of global warming - Natural cycles
Since the birth of the solar system, some 4.6 Billion years ago, the sun has got almost 30% hotter. Therefore it is one of the culprits for the cause of global warming.
The sun has other periodic climatic effects depending on the Earth’s orbit, tilt and so on.
Currently the atmospheric CO2 content is about 380 ppm (parts per million), up from about a thousand years ago at a level of 280 ppm, before 1750. It may go up to 500ppm by the end of this century.
The last time the Earth knew a really hot period was some 55 million years ago, the beginning of the Eocene period. Temperatures rose by some 8C at a time where temperatures were already slightly above what we know now and lasted 200,000 years!
For the past 2 million years, there have been ice age periods lasting 100,000 years. In between these periods there are 10,000 year interglacial periods of a warmer climate.
The Earth is at the end of the present interglacial and should be cooling down but it seems we are making sure we beat history!
Cause of global warming – but what to do?
We cannot stop global warming. CO2 will hang around for a long time and huge new consumer societies are developing fast, notably China and India.
Cannot do much about the sun but…
That’s a thought…
We could change our thinking and behaviour. Stop the major cause of global warming?
It’s been done before but this time we cannot take 500 years to see any effects from a Climate Change Enlightenment and Behavioural Revolution.
Let’s do it now. Our mindset is indeed a major one among
alternate energy sources.
Model interdependence, vulnerability and diversity in your life now.
Recognise the value of those people near you who are highly vulnerable and dependent. They are no more than a magnification of the human condition. And by getting closer to natural limits and fragility we may affect a change in mindset.
One of discernment about how much of everything we really need to flourish as people.
A changed mindset from exploitation to care removes a major
cause of global warming.
And good care is what the world needs right now.