Why is there still snow?

Last weekend we saw snowfall in regional NSW, but why is some of it still hanging around?

It seems strange that even though the snow fell a week ago, there are still piles of snow hanging around in some areas.

Surely the sun would’ve melted it? Isn’t the ground warm?

Well, apparently it doesn’t all rely on heat but a variety of factors.

Firstly, for matter to change from one state to another (aka snow going from a solid to a liquid) takes a massive amount of energy.

This energy is known as latent heat of fusion. It sounds intimidating, but is actually pretty easy to understand.

Basically, a large amount of heat has to be transferred into energy for the snow to melt.

So, if snow is more solid it will require more heat than other piles of snow (hence why some last a bit longer).

The next factor is rain!

Air acts as an insulator and snow is full of little air pockets, keeping it cold.

However, rain pierces through snow, breaking these air pockets and the snow’s insulation, working to melt the snow.

Finally, another reason for snow sticking around is due to the thickness of the pile.

If the snow is stacked up, less layers have been exposed to the sun so it takes longer for the heat energy to work it’s way through the pile.

Snow, however beautiful can be strange, so it’s nice to find out more on it’s oddities.