Climate chaos

Re: Anti- scientific climate model, John Robson, Jan. 20

Not mentioned by John Robson is the notion of “chaos,” which is taken much more seriously these days. When cream is poured into coffee, it is extremely difficult to predict how exactly the cream distributes i t self throughout the coffee, molecule by molecule. Weather systems are of course much more complex, and therefore prediction is vastly more difficult. There is a trend in the universe to greater disorder, and the recognition that some changes are irreversible. It is this fact that worries the environmentalists, most particularly how reversibility affects life on Earth, and how human activities contribute to this irreversibility. Life on Earth is the result of fine- tuning and organization, but we are however embedded in an environment of change, and we do need a strategy for handling disorder. We cannot avoid this trend to disorder ( also known as entropy). Certainly science can tell us more about the physical world, but our concern should be living-in-theworld, and not assuming that human lifestyle is the main mechanism for change, nor assume that when there is change it should be taxed. Gordon Watson, Rocky Mountain House, Alta. Any discussion of climate change should include how greenhouse gases, such as carbon dioxide, affect climate change. Since the Industrial Revolution there has been an i ncrease in atmospheric concentration of carbon dioxide, from 280 ppm ( parts per million) to 404.48 ppm measured in December, 2016, at the Mauna Loa Observatory in Hawaii.

Not all of the increase is due to human activity but it still has contributed its share of carbon dioxide from burning carbon- based fuels like oil and coal, and from agriculture and deforestation.

The science is strong that if greenhouse gas emissions continue at the present rate, the Earth’s temperature will exceed historical values, although we don’t know exactly by how much and by when.

What we must do to slow down increases in greenhouse gases is the most challenging decision the world faces today. Reiner Jaakson, Oakville, Ont.