Has the climate changed irreversibly?

Whether the changes to our planet’s climate become irreversible is not a question that has until recently bothered too many people; most scientists have been warning that the climate changes are in a process which, if nothing is done to arrest or reverse them will become irreversible and most agree that we have not yet reached a “tipping point” beyond which the changes cannot be reversed by human intervention.

I suppose in this context the word “irreversible” does not import the meaning of “permanent”. Our climate has always changes, and as far as we can measure mostly the changes have been slow enough to enable life on earth to adapt to them and to evolve with the changes in climate.

There have been the odd bursts of unexplained climate changes which have occurred over a few years, but these are very much the exception, rather than the rule, and they appear to have been localised in effect, rather than on a planetary scale. In this sense when the scientists are talking about “irreversible” climate change I believe that they are positing over a period of time that is linked to our imagination, or perhaps to our ability to predict something that is notoriously difficult to predict and of which detailed prediction has so far escaped us.

If humans change the climate of our planet in such a way that it will take a hundred or two hundred years to recover, then that is so serious as to be beyond our imagination.

A report is now being published in the Journal of the Proceedings of the National Academy of Sciences which concludes that the global average surface temperature will get higher and remain higher for a thousand years, creating less rainfall in Southern Europe, North America and parts of Australia.

The report points out that the oceans are expanding, which enables them to absorb and retain more heat, but eventually the laws of thermodynamics require the warmer ocean to release heat into the cooler air, causing the air to become warmer which in turn causes surface temperatures to rise.

If the scientists are right, then our challenge will be not to stabilise or to reverse global warming; things have gone too far for that. The challenge will be to slow down the rate of global warming so as to provide us with an opportunity to adapt to its effects and giving life an opportunity to evolve.

A temperature rise of 4 degrees Celsius will mean that we will radically have to change not only our way of life but it will also mean that in the long term some towns and cities will have to be relocated, vast human populations will have to move or die. These will be the fundamental changes that will affect us much more than any credit crunch or economic recession could possibly affect us.

We need to do more, far more than we are doing to slow down climate change. Keeping emissions at their existing level, or at 1998 levels or at 1992 levels will simply not work. No nation has yet created an anti-emissions policy. They have all rather dabbled in a little bit of anti climate change measures, which together, in the words of Rick Blaine do not amount to a hill of beans in this crazy world. Someday, the politicians and policy makers will understand that; let us hope that it will not be too late.

One Response

  1. thank you for reminding me about the seriousness of global warming

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: