The drought that has affected Western Australia since the 1960’s now appears to be linked in a new kind of “precipitation see-saw” effect with a correspondingly higher snowfall in East Antarctica during the same 40 years, according to two scientists who just published the findings in the journal Nature Geoscience this weekend.
Tas van Ommen and Vin Morgan of the Australian Antarctic Division suggest that there appeared to be simultaneous increase in severity in drought in Western Australia and an increase in snowfall in Eastern Antarctica, by comparing recent records of both regions. The researchers suggested that the “precipitation see-saw” effect itself may also be symptomatic of climate change.
“This does not appear to be in the range of natural variability: we can see from the ice core that an event like the increased snowfall at Law Dome would only come along once every 38,000 years without some change in climate patterns and, given the connection we see with Western Australia, it would suggest that the drought is also not a natural event” Dr van Ommen said.
The researchers were initially studying 750 year old ice cores at Law Dome on the coast of East Antarctica, when they noticed that the exceptional rise in snowfall over the last 40 years was unusual.
So they checked older ice cores till they found a similar snowfall level. It was in ice cores from 38,000 years ago.
Both extremes (heavier precipitation/drought) are examples of predicted effects of anthropogenic climate change, which calls for increases in both droughts and desertification in some regions with increased precipitation (heavier snowfall, more floods) in other regions.
Previous findings have found an apparent general correlation in climate changes between regions in the US – as the Northeast is experiencing heavier precipitation, the Southwest is drying out. But none have correlated the two closely, as this study suggests is happening between Australia and Antarctica.
Scientists widely agree that climate change is already causing major environmental effects, such as changes in the frequency and intensity of precipitation, both as rain and snowfall, as well as droughts, heat waves and wildfires; rising sea level; water shortages in arid regions; new and larger pest outbreaks afflicting crops and forests; and expanding ranges for tropical pathogens that cause human illness.
Excess snowfall; like East Antarctica is seeing, is a nuisance in inhabited continents like the US, and as it increases in the Northeast (snow) and Northwest (rain) in the future, it will be increasingly expensive for us.
However, in the long run, the other side of the coin – drought, like Australia is suffering – will be the much more dangerous of the two extremes for future human habitation on this planet.