DAISY: NASA spends lots of time and resources studying the weather.
And winter weather is particularly important.
That's why NASA sponsors the History of Winter workshop for teachers...
We'll take you to a frozen Lake Placid to learn about
the tools that measure the conditions of our coldest season...
Next on Real World.
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Winter conditions here on earth are very important to
NASA Scientists and engineers.
The agency's aeronautics mission relies on data
gathered during the coldest part of the year.
They use it to develop systems that will allow
planes to fly better and safer in winter conditions...
The exploration mission studies winter conditions, too.
Data related to harsh winter-like conditions here,
give scientists perspective about other places in the universe...
like the Moon or Mars...
ALLEN LUNSFORD: Now that we're discovering more closely,
ice on other planets, it's important to understand their properties.
DAISY: Allen Lunsford is a NASA computer scientist
and History of Winter technologist.
ALLEN: Not only of natural ice, on earth, but ice that
forms in other conditions that you don't find on earth.
Higher pressures, lower pressures, different
temperature regimes, the same concepts that we learn
here at H.O.W. are the concepts that are used by
scientists to study ice all over the solar system
DAISY: Teachers come to Lake Placid, New York and become
scientists for a week, rolling their sleeves up and
taking a hands on approach to understanding winter.
One of the things these teacher-slash-scientists do
is learn how to measure abiotic conditions of Winter.
Abiotic conditions are all the non-living elements of an
ecosystem, like air and soil, and snow and ice.
At Lake Placid, they use lots of tools for measuring these conditions.
One of the simplest tools to measure ice is called a
thermochron, and teachers at History of Winter
get a lot of use out of this tool.
ALLEN: A thermchron is a little data logger.
It has a clock and a little computer and some memory, so
it keeps track of time and temperature.
It's really kind of small, compact and rugged.
So you can connect it to a computer and program it to
record the temperature every minute, every two minutes, whatever you like.
It's rugged enough that you can bury it in the sand or
put it under water or put it in a snow pack, and later
retrieve it, connect it to the computer again, download
the data and then analyze the temperature history
that the thermachron experienced.
DAISY: Here's an experiment you can do with a thermochron...
Drop it in a glass of water... put the glass in the freezer, and let it freeze.
Then take it out of the freezer,
and let it melt.
This is going to talk a little while.
Once it's back to room temperature, pull the
thermochron out and check the data on a computer.
ALLEN: That's a great experiment, to show them the
concept of latent heat, where it'll start warm and come
down to the freezing point of water, zero degrees and then
it will stay zero for a long time, and as all the water in
that cup freezes, and then once it's all frozen,
only then does the ice start to get colder and it
will get as cold as the freezer. When you take it out of the freezer,
it'll get warmer, really quickly, right up to zero,
and then it will stay zero for a long time until all
that ice has melted and then it will get room temperature.
Those little areas there, where it maintains
temperature, even though it's absorbing heat or
releasing is that latent heat concept.
DAISY: Another Abiotic condition that scientists
want to learn more about is snow. And there are lots of
ways they measure snow at HOW.
TOM ALENA: You actually use what is called a snowboard.
DAISY: Tom Alena is a meteorologist at Talcott Mountain Science Center.
TOM: Not a fancy thing you go downhill snowboarding in.
It's a piece of plywood, maybe 2x2. You place it on
the surface of the snow before the storm.
And every six hours or so you measure the accumulation on that board.
DAISY: But then you have to reset the board. Cleaning
the accumulated snow off. This is very important.
TOM: The more snow that's on it, it's going to compact the
snow so if you went two days after the storm, and just
measured the one measurement, you might have a little less
snow than what really did fall.
DAISY: It's also important to measure the density of the snow.
TOM: We can calculate using those snow tubes, putting
them on a weight, a certain known volume, with a weight,
grams per cubic centimeter, and we can get densities.
DAISY: Scientists use this information to determine the
snow water equivalent.
This is the amount of water contained within a snow pack.
TOM: A layer of snow... how much water would be if you melted that down.
A good start is 10:1. So ten inches of snow would melt
down to a one inch layer of water.
Cold dry fluffy snow... that could be 2,0 even 30 to One.
The very heavy stuff, sleet is almost 2:1, and ice of
course, would be a one to one.
DAISY: More data about snow density can be recorded
simply by observing the snow flakes.
TOM: If they come out of the cloud base at that point, they are beautiful.
They're like little glass sculptures. However, if they
continue going through a lot of cloud, the cloud droplets stick to it.
It's called riming. Those crystals tend to have a lower snow ratio.
Moisture and temperature, very important variables in the cloud.
DAISY: There are a lot of very practical reasons to study snow density.
TOM: It's very important in watershed resources.
In the western United States where the Sierra Nevada
harbor the entire summer water supply for much of the big cities.
People there, doing core samples all the time in the
snow to look, how deep? How is its density?
And calculate how much water is up there for the spring and early summer melt.
DAISY: Studying snow density can also help predict avalanche dangers.
When snow of different densities get's layered,
one on top of the other, layers tend to slip.
Especially when you get a layer of low density icy snow.
TOM: That ice layer can really act as a slippery
surface for a brand new snow fall.
That's usually there where you'd expect slippage.
DAISY: So now you see why it's important to study about these topics.
But from NASA's perspective, the best reason to bring
these teachers up here is so they bring back great ideas
to the classroom, teaching kids to grow up thinking like scientists.
And those kids will be the ones who lead NASA forward
through the next generation, and continue exploring our
world and the worlds beyond.
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