Floods and storms: we ain’t seen nothing yet

Unprecedented floods and cyclones in Australia. Floods in Brazil and Pakistan. Huge snow dumps and storms in North America and Europe. Where is all the moisture coming from?

Out of the sky, obviously - but how’s it getting there?

The physics is straightforward. If you boil a pot of water, as you turn up the heat more water escapes as steam: evaporation increases as heat rises. Also, warmer air holds more moisture. There’s no mystery about it.

When this warm wet air collides with mountain ranges or undergoes convection, it reaches a point where it lets go its water content in the form of a deluge. The heat released as the water vapour condenses back into water at high altitude drives the convection process even harder, and you get even bigger dumps of rain and more flooding. Driving it all is one of the three hottest years in human history.

Anyone who still thinks this is natural climate variability at work needs to think again. The processes now under way mean that storms, heavy rainfall and floods can only get more severe from here on. That one-off tax levy to pay for the damage is liable to become a regular impost.

This should not amaze us. Australian scientists were among the first to warn that a warming atmosphere would bring bigger rain dumps and more flooding. That was in 1992, ladies and gentlemen, almost two decades ago.

Writing in the journal Climate Dynamics, CSIRO researchers Hal Gordon, Penny Whetton and Barrie Pittock, Anthony Fowler and Malcolm Haylock reported an experiment in which they had doubled CO2 in the atmosphere in a climate model which pointed to much heavier rainfall in the tropics and subtropics and more drought in the mid-latitudes. “The findings have potentially serious practical implications in terms of an increased frequency and severity of floods in most regions,” they concluded.

The researchers were concerned that their results, obtained from one of the earlier and less elaborate climate models, might be taken out of context or exaggerated by others and debated for a time whether or not to release them. But they concluded the findings were sufficiently serious to warrant their being brought to public attention.

In 1995 the warning was underscored in a paper by Anthony Fowler and Kevin Hennessy, who had run the scenario in three different climate models and obtained predictions of increased flooding rains that were consistent with the earlier ones and with current observations. They basically warned that flood prevention measures were likely to fail twice as often in a world with twice the atmospheric CO2, and this posed an unacceptable risk, especially for the poor and those living in flood-prone areas.

Warnings of increased frequency and intensity of rainfall and flooding were reiterated in a third scientific paper in 1997, and in a fourth in 2000 as well as in numerous international reviews and studies. Australia has thus been on-notice about the probability of recent events for many years and, true-to-form, did little or nothing.

As a society, it seems we prefer to have a disaster and fix it in retrospect with inquiries and taxes than to avoid a bigger one we can be fairly confident is on the way. Like generals re-fighting the last war, we are trapped in the past, repairing the last event rather than preparing for the greater one to come.

As a society, too, we are committed to increasing the scale, the damage and the suffering caused by such events - and this is the essential point which we all, especially politicians, tend to avoid.

Electricity consumption is rising by around 2 per cent a year, on the back of coal. Our coal exports continue to surge to feed the carbon monster in China. Demand for oil rises in line with increasing air travel, food miles and demand for transport. All of these things contribute to the record planetary warming that is sucking more moisture into the atmosphere to generate fiercer storms and bigger dumps of rain.

It is time we faced the unpalatable truth that the present policy of Australian governments, industry and consumers is to invite more and greater disasters - however noble and sincere our intentions or words may be. We are of course one country among many - but if every country waited for every other country to act on, say, healthcare we’d all be back in the middle ages, wouldn’t we? How many politicians do you hear saying we can’t afford modern hospitals merely because China or India lack them?

There is also the moral dimension. Currently about 1500 Australians die heat-related premature deaths every summer. By 2050, with rising population, the number is forecast to rise to between 4300-6300. Added to this we may also suffer several hundred bushfire and flood deaths annually, giving a combined climate-related deathrate three or four times as large as the national road toll. Over a decade, it may be similar to the price exacted on Australia by each of the two World Wars.

Is Australia, as a society, happy to sacrifice 50,000 of its citizens a decade merely so we can operate petroleum vehicles and burn coal? Are we happy for our politicians to consent to so many deaths merely so they can avoid taking the hard decisions, the right decisions?

We can argue ad infinitum whether the Queensland floods, the Victorian floods or cyclone Yasi were, as individual events, an outcome of climate change or freak occurrences. That is not the point. The point is that the scientific predictions are in clear agreement that the more carbon we release, the faster the planet warms, the more the atmosphere churns and the greater the evaporation and rainfall events that result.

We need to understand that those who advocate or practice inaction would have us risk more and greater disasters, and a heavier financial and human toll. In a society such as Australia’s, this is not acceptable.

It is time to heed the warning which the floods and storms are sounding.