Climate change models not perfect but all point one way

THE basic science of climate change is not very complicated.

Peter Campion and his climate denier ‘expert’ Dr Ed Berry should brush up on their science.

1) CO2 and methane are greenhouse gases that trap heat and as their concentrations increase in the atmosphere they will cause the climate to warm.

The increased energy trapped in the atmosphere corresponds exactly to the wavelengths of energy trapped by CO2 and methane, proving exactly where that heat energy comes from.

2) The concentrations of CO2 and methane have risen dramatically since the start of the Industrial Revolution (CO2 from 280 parts per million to over 400 ppm today and rising; methane, which is 29 times more potent a greenhouse gas than CO2, from 0.720 ppm to 1.85 ppm and also rising).

The average global surface temperature has risen by 0.8C since 1880.

Two-thirds of the warming has occurred since 1975, at about 0.15C to 0.2C every 10 years.

As a consequence, the oceans are warming, sea levels are rising, the total amount (mass), but not necessarily the area, of the Greenland, Antarctic, and Arctic ice sheets are declining.

However, the exact, year to year, prediction of precisely what will be the temperature, hurricane number and intensity, rainfall, blizzards, drought, jet stream course, ocean level and currents, glacier mass, etc., is considerably more complicated and even the best computer climate models are an approximation, within a given statistical error, of what will happen if the concentrations of CO2 and methane continue to rise.

Dr Berry argues that because the climate models are not 100 per cent accurate, they fail and can be ignored. He doesn’t understand that all quantitative scientific models and results, even Einstein’s, are considered correct within a certain probability – 95 per cent, 99.9 per cent, etc.

Climate models are no different, and each has a certain high probability of being correct (typically 95 per cent or better) within a given range of results.

There are many climate models and many predictions, some of which vary, yet all of which point in the same direction – that rising greenhouse gas concentrations will cause the climate to warm at an alarming rate.

What is the probability that all the models are incorrect? Virtually nil. Are all those (97-98 per cent) scientists and concerned citizens deluded, uninformed liberals who can’t think for themselves? I don’t think so. JIM TAYLOR, MUDGEERABA