Reporter: NASA's been looking at snow cover from space
for decades now but
they
they're learning a little bit more with the field
campaign using airborne
and ground instruments.
Here to tell us a little bit about is
Dr. Dorothy Hall from NASA's
Goddard Space Flight Center. Thanks for joining us.
Dorothy: Thank you for having me.
Reporter: NASA's satellites can see this snow cover
from space, how does this winter compare
to previous years?
Dorothy: NASA has a fleet of satellites
that measure the
Earth's land, ocean,
and atmosphere and of course that
includes the snow cover such as
you can see here.
Snow cover is highly variable
actually from week to week
month to month and between years.
If you look at the Sierra
Nevada snow pack in 2015
it was only
about 25% of normal.
Where as in 2017 this year
it's a 180%
of normal.
of normal. That's more snow then they've
seen there in about 20 years.
Reporter: So NASA scientist
are in the field right now testing
these advanced technologies to measure snow
like never before. What will these new
measurements tell us about snow?
Dorothy: NASA has been measuring
snow cover from space for decades
but the real challenge now is to measure
snow depth from space because that's
tells us how much water is in the snow
that we need to use for our water resources
so there is a major airborne NASA campaign
going on now where we can
are working on figuring out what is the optimum
combination of instruments that we can use
to measure snow depth from space on a
global basics.
Reporter: Can NASA see falling snow from space too?
Dorothy: Yes we can.
We have the Global Precipitation Measurement Mission
or GPM and
GPM is designed to measure
snow falling and rain falling and we can measure
that from space.
If you look at this animation of
a major storm that hit the east coast of the US
major snow storm in 2015 you can see
layers of snow and
this information, this data is very useful
for improving weather prediction models.
Reporter: Up to 70% of water resources
in the western US come from snow melt, California has been getting
heavy snow and rain recently. Does that mean the drought is over?
Dorothy: Actually it doesn't
mean that it's over. We are getting a lot
of rain, as you know, infact the rain is
over filling many of the reservoirs.
In California, but there's
a long way to go to restore and replenish
the ground water supplies.
The very important ground water supplies in Californina
help with irrigation of crops.
And so this is way we don't consider that the drought
is over. It will take several more years of
above average precipitation to
replenish those ground water supplies.
Reporter: How does snow impact parts of the country
that rarely see any snowfall?
Dorothy: If you walk in
to any super market
and you look at the produce
you realize that about
half of the produce
that we eat
in this country comes from the
central valley of California
and the central valley
gets a lot of it's water for
irrigation of the crops from
snow melt directly from the
Sierra Nevada mountains.
So that directly influences us.
Even if we don't have snow
cover in our particular region where we live.
Reporter: Where can we learn more?
Dorothy: If you go to snow.nasa.gov
you can learn more about the ongoing SnowX campaign
that's going on now in Colorado
as well as a lot more information on satellite
remote sensing in general.