Hoar Frost…

Hoar frost: (also called radiation frost or hoarfrost or pruina) refers to the white ice crystals, loosely deposited on the ground or exposed objects, that form on cold clear nights when heat is lost into the open sky causing objects to become colder than the surrounding air. A related effect is flood frost or frost pocket. which occurs when air cooled by ground-level radiation losses travels downhill to form pockets of very cold air in depressions, valleys, and hollows. Hoar frost can form in these areas even when the air temperature a few feet above ground is well above freezing. Nonetheless the frost itself will be at or below the freezing temperature of water.

Hoar frost may have different names depending on where it forms. For example, air hoar is a deposit of hoar frost on objects above the surface, such as tree branches, plant stems, wires; surface hoar is formed by fern like ice crystals directly deposited on snow, ice or already frozen surfaces; crevasse hoar consists of crystals that form in glacial crevasses where water vapor can accumulate under calm weather conditions; depth hoar refers to cup shaped, faceted crystals formed within dry snow, beneath the surface.

The name hoar comes from an Old English adjective for showing signs of old age, and is used in this context in reference to the frost which makes trees and bushes look like white hair. It may also have association with Hawthorne when covered in its characteristic white spring blossom.


Yesterday when we woke up it was a beautiful foggy day.

Mr.M noticed that it looked like there was hoar frost on all the trees, so we went outside and explored for a bit. It was so beautiful! Monkey was very fascinated by it all and had to touch every one. By the time we got outside, the sun had come out and it was starting to melt, so it wasn’t quite as spectacular as it had been earlier, but still pretty. 

Good time to test out the new camera too..! It makes me want to re-do all the posts I did in the time frame when the camera broke…(if only!)








Weather Unit

Science is a pretty big deal for our family. We get pretty excited about it. Especially Mr.M. Okay…mostly Mr.M. 😉

So you can imagine it was a pretty awesome day when a cool, thick looking package arrived in the hands of Mr.Fed Ex man.


We had just come home from our afternoon walk. As I’m heading into the driveway, a creepy looking van with the door open pulls up right behind me. You can imagine my thoughts. Just as I was about to run though, I realized, somewhat tentatively, that it wasn’t so bad…only your “friendly” neighborhood Mr.Fed Ex man. He smiles at me, (standing back within the required “no grab” distance), and says “GREAT! I don’t even have to get out of my vehicle! This is going to be the easiest delivery ever!” I smile back at him, not really sure what to say, (especially considering what I was thinking of him before). Then he just sits there, really far away from the door, holding out his little device for me to sign. At this point I realized I’d better get over my fears of getting too close to the van and just sign the thing, or I wouldn’t get that fat looking package. Am I the only one that has a fear of getting too close to vehicles that pull up beside me? This was majorly drilled into me at the “stranger danger” presentation by the RCMP last year that Mr.M went too. Anyways, yes, I know…I’m paranoid. 😉
So, I digress. Anyways, it was so exciting to get our very first little curriculum package from our new support school library. This one was the Weather unit. SO cool that they put it all together and mail it out to you for free! We only have it for two weeks, and are winding down our studies on Saturday. Normally I like my Saturdays home school free. I’m just like that, ok?! But we have one more day that we couldn’t fit in, and so I’ve had to give in. Sigh. Of course Mr.M is ecstatic!

We’ve been working through the unit, and really enjoying ourselves. We’ve been using a book called Weather Watch by Scholastic. For the life of me I can’t find it on Amazon right now, but if I manage to become un-lazy (is that a word?!), and get the author, then I’ll link it later. It’s a nice book, with some really neat experiments in it. The only problem is…a lot of them haven’t been working! We end up having to “tweak” them or look online for a better way. It’s a bit frustrating, but I guess it’s good for us to be more inquisitive and learn how to solve our problems…;)

science word map


These are some pictures from our first experiment on atmosphere. We were investigating air by trapping water inside a measuring cup and then sliding an empty little cup up underneath of it. When we slid the little cup up underneath, we realized it wasn’t really empty after all! It was filled with air! The cup floated to the top of the measuring cup with it’s trapped air.

The boys were pretty excited about this experiment. We had to do it over and over again, and Mr.M begged me to leave it up so he could repeat it for daddy when he got home ;)

The boys were pretty excited about this experiment. We had to do it over and over again, and Mr.M begged me to leave it up so he could repeat it for daddy when he got home 😉

Trapped air! Can you see the little cup floating at the top?

Trapped air! Can you see the little cup floating at the top?

Here’s a few more pictures of the obligatory “Tornado in a Jar” experiment. The book called for us to put some dish-soap in. It didn’t specify how much, so we put about 1/2 tsp. That was waaaay too much! It was just a bubbly mess. So Mr.M dumped his out and put one drop in, which worked like a charm.

What kid doesn't love a tornado in a bottle?!

What kid doesn’t love a tornado in a bottle?!

So all in all it’s been a pretty fun couple of weeks. We did quite a few other experiments, but I didn’t take pictures of them all. Maybe I’ll post some pictures of the weather artwork that the boys did later. Just in time for….snow! But let’s leave that topic to rest for now….;)