WHAT DANGERS LIE AHEAD? by James E. Lovelock (1994)
. . Even if we reform immediately, we shall still see the Earth change and we, its first social intelligent species, are privileged to be both the cause and the spectators. The imminent change in climate is as large as between the last ice age and now.
To comprehend the magnitude of the change ahead, glance back to the depth of the last ice age, some tens of thousands of years ago. Then the glaciers reached as far south as latitude 35 in North America and to the Alps in Europe. The sea was more than 100 meters lower than now, and therefore an area of land as large as Africa was above water, and where plants grew. The tropics were like the warm temperate regions are now. In all, it was a pleasant world to live on, and there was more land. What will happen, as a result of our presence so far, will be a change as great as that from the last ice age until about 100 years ago.
To understand what has already begun and will develop in the next century, imagine the start of a heat age. Temperatures and sea level will climb, by fits and starts, until eventually the world will be torrid, ice free, and all but unrecognizable. Eventually is a long time ahead, it might never happen to that extent; what we have to prepare for now are the incidents of a changing climate, just about to begin. These are likely to be surprises, things that even the most detailed of big science models do not predict. Think of the ozone hole--this was a real surprise. The most expensive computer modelling and monitoring of the Earth's ozone layer failed to see or predict it. It was seen by observers looking at the sky with simple instruments. Surprise may comes as climatic extremes, like ferocious storms, or as unexpected atmospheric events. Nature is nonlinear and unpredictable and never more so than in a period of change.
This is an occasion when we cannot look to Gaia for help. If the present warm period is a planetary fever, we should expect that the Earth left to itself would be relaxing into its normal comfortable ice age. Such comfort may be unattainable because we have been busy removing its skin for farm land, taking away the trees that are the means for recovery. We also are adding vast blanket of greenhouse gases to the already feverish patient.
Gaia is more likely to shudder, then move over to a new stable state, fit for a different and more amenable biota. It could be much hotter, but whatever it is, no longer the comfortable world we know. These predictions are not fictional doom scenarios, but uncomfortably close to certainty. We have already changed the atmosphere to an extent unprecedented in recent geological history. We seem to be driving ourselves heedlessly down a slope into a sea that is rising to drown us.
We must, in our own interest, recognize that our planet is at least as important as we are. If we continue to pollute and destroy for narrow self interest, we could bring about the end of the Pleistocene and the dawn of a new hot Earth. The future depends on decisions made now on the supplies of food and energy. We must moderate our passion for human rights and begin to recognize the rest of life on Earth. Individual risk, such as of cancer from exposure to nuclear radiation, or to products of the chemical industry, are to be prevented, but they are no longer the most urgent concern. First in our thoughts should be the need to avoid perturbing Gaia and exacerbating its present natural instability. Above all, we do not want to trigger the jump to a new but unwanted stable climate.
http://www.geocities.com/~gaiachurch/lovelock.html