Is Tasmania a climate refuge?

The Tasmanian temperature anomaly over 12 months

The Tasmanian temperature anomaly over 12 months, the time period stated on the map

The Tasmanian vegetation index anomaly over one month

The Tasmanian vegetation index over one month, taken in 2019, a traditionally dry month

The Tasmanian rainfall anomaly over six months

Tasmanian rainfall anomaly over six months, taken earlier in 2019

Is Tasmania a climate refuge?


But it is not escaping climate change.

The Bureau of Meteorology anomaly maps here are self-explanatory. They don’t mean a lot on their own, but they do seem to be following recognised trends.

Keep in mind that the West Coast is a wet part of Tasmania, a place where thick moss grows on roadsides. That has started to change, and the West Coast now burns in summer. The wildfires are usually ignited by lightning strikes.

Look through our blog posts for details on the most recent big fire.

The vegetation map shows the darkest (lowest) vegetation in areas that burned this summer. Keep in mind that summer is around Christmas in the southern hemisphere.

Long-time locals in southern Tasmania tell us that autumn rain has diminished in recent years, and that residents managed decades ago with fewer rainwater tanks. This anecdotal evidence is confirmed by historic rainfall and river flow data, which shows September and October (spring) are now when it rains most, and the November to May period is drying.

This is possibly further confirmed by recent bushfire seasons, especially the almost-disastrous 2018/19, although it is near impossible to pin any one event on climate change.

Official rain trend maps and data don’t tell the full story.

Though annual rainfall may be much the same as in years past, the way it falls appears to have changed, with fewer extended periods of drizzle, replaced by less frequent, heavier, shorter downpours. These invariably fall on harder ground, running off rather than soaking in if there is any gradient.

The proof is in the forests. Trees have died in recent years, the white ghosts visible on the hills, presumably perishing from a lack of soaking rain penetrating the soil, and extra heat.

Once weakened by drought, even tough eucalypts like blue gums succumb to borers. We have seen it in our own yard.

The death of trees globally is well observed, lists like this make sombre reading.

So, is Tasmania a climate refuge?

Buying rural property in Tasmania away from flammable forests, especially pine monocultures, in an area where you can get sufficient water for growing crops during the harsh summer hot periods, is a climate refuge option.

The state is cool for most of the year, and the fire season is short, from late November to March, with December to February the danger months. Tasmania is a windy place, and often dry, so there is a potentially catastrophic fire problem. House and garden should be set up accordingly, and evacuation plans made early.

There are already people moving to Tasmania with climate change in mind, as this writer can attest from inquiries with new arrivals.

Looking out the window today, it is cool, with blue skies … but what will summer bring?

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