Ewan McGregor: We've kicked this planet around for long enough

Every country has accepted that human activity is responsible for climate change, writes Ewan McGregor. Photo / NZME

Though diminishing, there are still those who deny that climate change, at least as being the result of human activity, is occurring and are dismissive of man's efforts to combat it. Or it could be regarded as a lost cause, so why worry?

Whatever, the frequency of extreme weather patterns around the world must surely cause alarm and portend declining habitability of the planet for human and other life. I have no doubt this obligates us to strive for a planet able to allow succeeding generations to live as we have lived. Yes, we have much to worry about – and much to be thankful for too - but deteriorating climate overshadows all our challenges.

Life on this planet has evolved over hundreds of millions of years. Until recently it was relatively stable, with the exception of traumatic extraterrestrial events, allowing ecological evolvement to subtly shift to meet changing conditions, most likely natural climate change, something that has been a constant but slow process, quite unlike that of today.

The first act of man to destabilise the climate was to destroy the planet's lungs – the natural forests that clothed most of the landmass. This had its origins with the Neolithic Revolution (also known as the Agricultural Revolution), beginning about 12,000 years ago in the Middle East region of the Fertile Crescent. This marked a historic transformation of civilisation's structure, indicated by the decline of the small, nomadic groups of hunter-gatherers that characterised society.

Thenceforth, people took up farming, and as productivity increased beyond what was needed to feed the family, excess was sold, hence the birth of agricultural trade. Thus, villages grew into ever-enlarging cities as productivity increased through genetic improvement and aided by irrigation and fertiliser and, in recent times, mechanisation and the use of agricultural chemicals. The forests were in the way of the would-be farmer and the destruction began.

Today over half the forest has gone, and most of that over the past two centuries. The process continues, mostly in the tropical regions.

There is no better – and more ruthless - example of this destruction than New Zealand, the last significant landmass by far to be inhabited. The Māori destroyed about half our forests through the act of fire, spread unintentionally, or deliberately for various reasons, though only to a small extent for cultivation. In the North Island, at least the forest very slowly began to regenerate (if not refired), but in the South Island, permanent tussock grasslands usually became established.

That hastened with the arrival of the European, who took forest destruction to a new level so as to make way for, initially, wool production, but after the development of refrigerated shipping in the early 1880s, to produce meat and wool. Then the destruction really began. By the outbreak of the First World War, the great extent of our magnificent, unique primeval forests had been forsaken. It is estimated just 10 per cent was harvested for timber (though nearly all of the kauri).

Such has been the reduction of the forests. Now add to that the combustion of fossil fuels - coal, oil and gas – which make up 85 per cent of the energy source we use for transport, heating and electricity generation and which have taken hundreds of millions of years to form. It is really only the past century or so that we have exploited the oil, a little longer for coal, and much less for gas. How much have we used? Or, more to the point, how much is left? The rate of extraction today is massive, and increasing as global affluence and population grow, projected to be about 10 billion by the middle of this century.

Does one need to be a scientist to fear that this process is damaging our climate – and planet generally for that matter? I think not. We've kicked this planet around for long enough. Amongst other things, we need to wean ourselves off fossil fuel because, apart from the consequential climate disruption, sooner or later it's going to run out. We had better be prepared with alternatives in place, otherwise civilisation as we know it will be imperilled.

Fortunately, over the past decade or so, exciting technological initiatives have been made that offer far-reaching possibilities, and are already being applied, though as yet far from making a dent in oil consumption. Solar and wind power have been well demonstrated as offering sustainable electricity, and don't warrant the ridicule to which they are too often subjected. In harness are significant advances in battery technology. Expect greater advancement in the years immediately ahead, driven by escalating fuel prices.

Every country has accepted that human activity is responsible for climate change. The hard part is to induce the constituency to accept the disruption and costs involved in the solution. It is time to cease the cynical attitude to these innovations.

Of course, it will take a little time for them to be applicable as a serious substitute for fossil fuel use; but remember that it has taken one and a quarter century for motor cars, trucks and tractors to reach the wonderful engineering standards of today. Yes, they were rather primitive to start with and many sceptics thought a horse was more reliable.

My bet is that over the next 10 to 20 years we will see a widespread uptake of these technologies for there's no alternative on the horizon. Necessity is the mother of invention, and she'll be of acceptance too. So, there's hope, as there must be.

Ewan McGregor is a Waipawa farmer and former Hawke's Bay regional councillor.