Climatologists say greenhouse gases are largely to blameExperts agree the region is drying out at a globally significant rate.
The cold fronts and lows that cross the region during the cool months of the year, bringing rainfall and storms, areHigh pressure systems, which help suppress the development of rain systems and create warm, sunny days, are getting stronger and more frequent.Dr Hope said it was a pattern happening right across the subtropics of the southern hemisphere.
“If we have a regional shift in where the rain falls, that will have a big impact on this small region of a big continent.”To better understand what’s behind the changes, Dr Hope said you had to look above the surface and into the way the Earth circulated its air around the globe.For southern Australia, a big part of it is a pattern known as the Hadley Cell.
In the winter, it migrates north, extending over central parts of Australia and allowing rain-bearing systems like lows and cold fronts, to sweep over the South West.In a normal summer the subtropical ridge and westerlies move south and in a normal winter they move north.But Dr Hope said heating caused by greenhouse gases had been tinkering with the delicate way air flows around the atmosphere.
Dr Hope said one of those changes was the downward branch of the Hadley Cell had been intensifying in recent years, and had also been expanding toward the poles.
lol horsesh!t, this is nothing new for WA, since the days Moses was panning for gold there