The International Panel on Climate Change predicts a global temperature rise of about 5C by the end of this century. Thats enough for major changes. Like in rising seawater levels, in food production and rainfall.



Knowing why we are in this fix is the first step to doing something about it. Yes, thats you and me.

There are four levels at which to understand the cause of global warming.

* The mechanics of global warming

* What we do

* Our beliefs and values, and

* Natural cycles, involving the sun

The mechanics of global warming are simple. Theres too much carbon dioxide (CO2) in the atmosphere.

The Earth absorbs heat from the sun and radiates much of it back into space or else we would cook. But presently the Earth retains more warmth from the sun, about 0.85 per square metre, than it radiates back into space. It is mainly CO2 that hinders solar radiation back into space and this creates the greenhouse effect.

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. Predictions are that it may go up to 500ppm by the end of this century.

And CO2 hangs around for a long time. It takes about 100,000 years for atmospheric CO2 to reduce by about 63% through natural processes.

What we do contributes to so much CO2 in the atmosphere. It got there because of massive amounts of fossil fuels that humanity has been burning since the start of the Industrial Revolution, some 300 years ago.

Coal and oil are the mainstays in power generation and to power our transport. Of course a growing world population needs more energy for food, clothing, housing and comforts. But when there are 8 billion of us, all wanting a big house, the latest electronic playthings, a car, and access to world travel, were in trouble.

Were in trouble because the Earth cannot physically support all those needs and wants and because the energy emissions needed to meet them would choke us.

Our beliefs and values have much to do with why we want so many more things than we really need.

It is to do with ideas about progress that started before the Industrial Revolution, during the period known as the Enlightenment, starting in the 16th century.

It generated ideas about the importance of the individual, about the use of reason and material wellbeing. Rene Descartes was one of this periods foremost philosophers. You know his famous quote: I think therefore I am. Recently I saw an advertisement using that quote like this: I think, therefore I shop.

Funny? Yes, and getting to the heart of the problem. The way we think, about ourselves and about the world is the problem.

Does our consumer world leave room for nature, for things we can make and maintain ourselves, for slow and natural growth, for each other and our environments? Not much.

So, its our values and our beliefs that continues to put CO2 in the air and are cooking us.

Natural cycles, involving the sun have something to do with global warming too. Thats true.

The Earth is now receiving 30% more solar radiation than it did 4.6 billion years ago. And there have always been cycles of ice ages and warmer interglacial periods, depending on the Earths orbit, solar radiation strength and changes in ocean currents.

The last Little Ice Age was between 1400 and 1840 with significantly lower temperatures. And such events are part of 1,500 year cycles.

Presently the Earth is at the end of an interglacial, warmer time and is due for a cooling down. But it seems that we are not going to let that happen. The steep increase in CO2, particularly over the last 45 years, does not fit into any natural cycle.

We cannot blame the sun. Its us.

What to do is the question. The facts are that global warming will be with us for a long time, whether we stop putting CO2 into the air today or not. It will get worse as fast developing economies involving billions of people in the USA, China and India will rely on fossil fuels for decades yet. Renewable energy is only at the start of making any inroads.

You can only change what you do by changing how you think. If we dont figure our way out of our consumerist addictions we will eventually have to go cold turkey. Or is that hot turkey?

There is a need for re-valuation of living well with an interdependent, connected and unpredictable world. One with limits.

What better way to change your thinking than by getting close to people who do live and some do so very well - with high levels of vulnerability and dependence, like people with disabilities or those who are frail aged.

Giving a hand to those who live in your street or come on your path, is a way to get reconnected with what life is all about.

Whether or not alternate energy sources will be used in time to make global warming tolerable, getting on with each other, in all our diversity, is good for planet Earth.

And for you.