Kicking Up A Stink

The UK has been experiencing ever-freaky weather conditions.

Yesterday six inches of snow fell in Scottish town Aboyne, where, last week, the temperature soared to 23.6C, making it the hottest March day in Scotland on record.

The Environment Agency has confirmed that south and east Yorkshire have joined East Anglia and southeast England as areas affected by drought; seven water companies are enforcing water restrictions, such as hosepipe bans, from Thursday the 5th of April.

To make the most of our hosepipe, I forsook a shower today, and was instead hosed down in the garden.

And to presumably prevent a petrol- or pasty-style panic, the BBC has published some water-saving tips, one of which is 'Wash cars using a bucket, or just keep headlights, mirrors and windows clean.'

Okay...

Today we actually had some rain. I was caught out in it, whilst walking my dog, and experienced something I'd totally forgotten - the strange smell that appears after it's rained for the first time in a while.

You know that distinctive odour; it's similar to the smell of tarmac, or Wellington boots - or is that me just making an association?

But it has a name: petrichor.

And apparently it's caused in a number of ways. Firstly, rainwater causes spores of the bacteria actinomycetes, which grow in soil, to launch into the air, which are then diffused in the moist post-rain atmosphere. Actinomycetes prefer damp soil, so often reside in woodland, and produce a sweet smell sensation.

Secondly, rain can be acidic, as we know, especially so because of chemicals in the atmosphere particularly above urban areas. High acidity in rainfall can smudge up soil, causing the release of minerals, and can react with petrol and other chemicals on the ground, causing a stink not quite as pleasant as the first smell described.

The third cause of petrichor is the release of oils by trees and plants during dry periods, oils which are absorbed by soil and rocks, and then mixed with rainwater and the organic compound geosmin, which translates as 'earth smell', and also gives beetroot its earthy flavour. 

This smell is so nice it supposedly has been bottled, and is akin to the first described.

Bottled beetroot. You learn something new everyday.