If you are old enough to read and understand this, you will probably be safe from the worst effects of global climate change. If you are too young to read and understand this, your mid-life future may be less than comfortable. By the time today's young children reach middle age, the disruptive effects of global warming may be causing enough ecological imbalance to unsettle human populations and initiate significant political chaos. The children of today's children may be facing even more sobering prospects.

These are the predictions coming from climatologists as their science becomes more sophisticated, their computer modelling more refined and their information more current. As for the scientists themselves, their concern is rapidly moving to alarm as they chart their findings and consider the environmental implications. Undoubtedly, we will learn more about their assessment with the approaching December meeting in Copenhagen of the United Nations Climate Conference, an event that will attempt to create a successor to the Kyoto Protocol. In the interim, however, we already know a fair amount about the reasons for alarm.

First, the 2007 predictions concerning the impact of global warming by the Intergovernmental Panel on Climate Change (IPCC) have been far too conservative. The most current science used to support the IPCC's assessment was already dated by nearly a decade because of the time taken to do studies, peer-review them, agree on relevance, reach consensus ‹ both scientific and political ‹ and then write and present conclusions. Newer studies and more innovative technology reveal that impacts on climate from rising levels of atmospheric CO2 are much faster and more dramatic than previously reckoned by the IPCC.

Alarm is also being fed by the dismal efforts of countries to reduce their greenhouse gas emissions ‹ emissions have been going up rather than down ‹ and many initiatives now in place are half-hearted and inadequate. From the pre-industrial base-line of 280 parts per million of carbon dioxide ‹ the level that would presumably give us "normal" weather ‹ we are now at 388 ppm. A further rise to 450 ppm seems certain and even 650 ppm is likely. These concentrations mean average global temperature increases of 2°C, 4°C and 6°C respectively. Time lags of a decade or more between emissions and actual impacts on climate mean that we are committed to consequences that are yet to arrive.

The information we are getting about oceans is also raising alarms. We now know that the world's oceans are a prime driver of global weather and that they have been absorbing most of the heat generated by greenhouse effects ‹ water absorbs nearly 1,000 times the amount of heat as air. As the oceans warm, however, they are less inclined to absorb more heat. Also, warmer water holds less dissolved gas, meaning less oxygen in the oceans to support sea life and more carbon dioxide in the atmosphere to cause other changes.

On land, small increases in atmospheric CO2 levels seem to stimulate plant growth, generally increasing the size of stems and leaves but decreasing seed and fruit production ‹ not good news for agriculture. Rising temperatures can also impair fertilization, particularly in low-latitude regions where crops are already near their limit of heat tolerance. Changing weather patterns can cause drought and desertification, further disrupting plant growth. Since we have been supplying our food needs for millennia by matching plants, soil and water to climate, any change in any of these factors can cause us major problems. Under global warming conditions, for example, desertification will exclude large areas from present food production, and grain growing can't be shifted to more northerly climates because of inappropriate soils.

Methane release is also cause for alarm. At about 25-times the warming effect of carbon dioxide, huge amounts are being released in increasing amounts from melting permafrost, muskeg and deep-ocean deposits ‹ they are held in place here by high pressure and low temperature, so warming oceans can destabilize them.

Global warming is also melting glaciers, with erratic effects on river flow. But an even greater major concern is the accelerated and unanticipated melt of ice in Greenland and West Antarctica. Since the IPCC's 2007 report, estimated ocean rise has been tripled to about a metre by the end of this century. This will cause increasing concern to today's children and their children as coastal cities are flooded and valuable food-producing estuaries are submerged. Hundreds of millions of people will be displaced.

Such sobering prospects raise the philosophical question about whether or not we should know what is happening. Should we confront this bad news or should we just be left in ignorance to live our lives in innocence until we ‹ or our children ‹ have to face the inevitable? Have we already reached the point of inevitability? If so, is it too late to care? Should we tell our children?

The latest information on global warming and climate change is a pall settling on everyone who considers the future, whether it be ecologies or the viability of human civilization we bequeath to our children and their children. Indeed, contemplating the forthcoming decades has become a disquieting exercise, with even the most promising of assessments now couched in qualified optimism. Even scientists want their predictions to be wrong.

Most politicians and most people still seem to be in denial, living mostly in a world of the present. They awake in the morning to a seemingly ordinary day, dress accordingly, then carry on as if everything were normal. But some very knowledgable scientists are looking intently at their climate models, checking and triple checking the accuracy of their data, then considering and re-considering their predictions. From their perspective, to be frankly honest, the future looks sobering.