By JR on Friday, September 23, 2011
Contrary to what the author says below, the graph appears to cover just one ski location: Spencer's Creek, which reminds one of Keith Briffa's solitary Siberian tree. None of the other trees fitted Keith's global warming story so he relied on the one tree that did.
And Australia has had unusually early openings to its ski seasons in recent years so why is that not reflected in the graph? It could be that we are getting less extreme weather. The average depth rather than the peak depth would be more informative. The Greenies keep shrieking that were are having MORE extreme weather but a lot of data show the opposite. America has had unusually few major hurricanes in recent years, for instance
But the major point is that snowfall in most locations is more influenced by available atmospheric moisture than by temperature, and Australia DID suffer one of its recurrent droughts up until recently. If there is a real effect there, it's a drought effect
Look at this graph. Each blue bar shows the peak annual snow depth at Snowy Hydro’s five official snow measuring stations at Spencers Creek, about halfway between the NSW ski resorts of Perisher and Thredbo.
The black line shows the downward trend over the last 58 years. Pronounced decline, isn’t it. The consistent big seasons of the 1950s, ‘60s and ‘70s are a thing of the past. On average, we’re losing three quarters of a centimetre of snow each year. That’s nearly half a metre since records were first kept.
Snowy Hydro has taken these measurements since the 1950s because they like to know how much snowmelt is going to end up in their dams each summer. The information is neutral, reliable, and untainted by ski resort PR. Even more crucially, it relies not on pie-in-the sky computer modelling, but on clinical, unhysterical observation.
And those observations reveal beyond doubt that Australia is getting warmer.
The problem with the climate change debate is that most of us can neither observe, nor feel, the data presented.
We cannot detect small annual changes in temperature, and are no hope of perceiving increases in CO2 or other gases. Moreover, popular graphs like the “hockey stick” championed by Al Gore, are endlessly open to misinterpretation and dispute.
But there’s no arguing with this snow depth graph. It is elegantly simple and best of all, it represents something tangible. The graph clearly shows that less snow is falling, and less snow is sticking around. And that ain’t happening because the world’s getting cooler, as some argue.
A warming globe impacts the Australian snow pack in two simple ways. Firstly, and most obviously, warmer weather means a greater likelihood of rain instead of snow, and quicker melt after snowstorms.
The second effect is a little more technical. Basically, a warmer globe makes it tougher for the snow-bearing cold fronts in the Southern Ocean to push north and make landfall on the Australian continent. Most experts agree that’s why areas like SW Western Australia are drying out so rapidly.
Now, no one’s saying the snow is going to disappear entirely this century, as predicted by a 2003 CSIRO report with a distinctly doomsday tone. But slowly, it’s going.
The $64 million question is why. Is all this part of a natural cycle or is the hand of human activity at work here?