The Australian Climate: Humidity Explained.

It’s time to get hot and sweaty. Yes, today I’m going to be talking about humidity. I don’t have any photographs of humidity, but that’s probably a good thing.

This is rocket science! No, it is, really! I have tried to understand humidity and the more I read the more confused I get. So if we have any rocket scientists reading today, perhaps you can leave a comment and clear up my confusion.

But in the absence of any intervention by a person with a brain, here’s my understanding of humidity. To understand humidity, you need to understand the following terms:

• Absolute humidity
• Specific humidity
• Mixing ratio
• Vapour pressure
• Saturation
• Saturated vapour pressure
• Dew-point
• Frost point
• Wet-bulb temperature
• Relative humidity

I don’t!

I’ve tried, but by the time I have read and understood the definition of the last one on the list, I’ve forgotten what the definition was of the first one on the list. I’ve been in this never ending cycle for about an hour and a half now.

So now I have a headache as well as feeling very sweaty.

So let’s try a different approach.

Yesterday, here in Brisbane, it was unbearably hot and sweaty. The worst I think it has been since my arrival here in November 2007. I had the misfortune to have to shovel some dirt off of the pavement, (heavy rains washed topsoil over it) just a 10 minute job, but by the time I’d finished my entire T-shirt was drenched.

I know, yuck, sorry.

Here’s what the weather stats said about Brisbane’s humidity yesterday.

Brisbane

Temperature 26 °C
Dew Point 24 °C
Humidity 90%

Lets contrast that with the information for a town called Ballarat, which is in the state of Victoria. It’s a long way south from here and about 100 km west of Melbourne. These stats were taken at the same time yesterday….

Ballarat

Temperature: 26.5 °C
Dew Point: -5.2 °C
Humidity: 12%

Note: dew point is a good measurement of how “sweaty” it’s going to feel. It’s a much better measurement than relative humidity which is almost certainly the humidity measure quoted above. Dew point is the temperature the air would need to be cooled to to achieve 100% saturation.

Hopefully, you can see how close we all were in Brisbane to that saturation point?

So, if I had been shovelling my dirt down in Ballarat, you can rest assured I would not have broken sweat. But whilst the skin of the good people of Ballarat dries out like a prune, my skin continues to feel as soft as the proverbial baby’s bottom and I will look younger than Cliff Richard when I’m 105.

So short term, I may look horrible and sweaty, but long-term it’s good for my appearance. Additionally, you can enjoy the benefits of what I call the “sweat yourself slim while you sleep” diet. I think I lost three pounds last night.

I hope that clears up the humidity thing.

Any questions?

Yes, where does humidity go?

Glad you asked. Yesterday at around 11.30 a.m. here in Brisbane, humidity dispensed itself all over the city in a frenzied downpour, commonly known as flash flooding.

Like this………

And with that, looks like I have some more dirt to shovel away from the path.