sarahkeenihan

It’s another scorcher!

In January 2014 on January 21, 2014 at 2:27 pm

kirsti burning australia

Kirsti: Having endured the past week, you might not be surprised to know that this time last year was also hot. It reached almost 50oC in Moomba, South Australia in January 2013, and in Narrabri NSW – where we were driving a fortnight ago –  it reached almost 48oC. In fact, have a browse of the daily extreme temperatures during January yourself – WA and QLD peeps are cooking eggs on car bonnets every day!

But this is not a post about climate change, even though it is contributing to these hot summers. It is about localised heatwaves, which are heralded if the temperature has been extreme for 3 days in a row; ‘extreme’ is relative to the time of year. You can check if there has been a heatwave in your area on an amazing website called Scorcher too, but it doesn’t tell you why it has occurred.

The thing is, heatwaves are caused by a complex combination of long- and short-term factors. Uber-long-term factors include global warming, both natural and man-made. Australia has warmed steadily since the 1940’s. But medium- to short-term factors are what interest me most at the moment. Warm winters preceding summer can increase temperatures across the continent, and high pressure systems (characterised by clear dry days) are also responsible for the local warming of air. Dry soils do not absorb heat as effectively as those holding water, which can act to heat the localised above ground air. But probably the most important is the fact that it is warmer more often and for longer periods of time. Recent heatwaves in Australia are essentially an extension of the preceding record breaking hot days, even months, exacerbated because it is mid-summer.

I would advise at this point to check the forecast and consider the previous month’s temperatures before embarking on a roadtrip into western NSW and southward.  Our two kids, trailer and 1996 Nissan Patrol can attest to it being one hot and sweaty trip spotting willy-willies, wheat and windmills!

NB: Image is a digital alteration of one of my own photos. 

[disclaimer: the heat + travelling in the heat is why I’ve been absent from here too!]

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: