Today joining us to help us understand the science behind Earth's severe weather,
we have Dr. Dalia Kirschbaum. Thank you for joining us today.
Thank you for having me.
We are going to be discussing primarily a program you are very familiar with, the Global Precipitation Measurement Mission
and how it helps us see weather around our planet Earth. So tell us a little bit more.
That's right. So Earth is a really complex system and understanding how water, which is Earth's most precious resource
moves from the atmosphere to the ground, to the underground is really important for understanding the global water cycle.
Now, GPM looks at precipitation and it helps us to understand what's happening with rainfall, everything from light rain to heavy rain and snow
all the way from the tropics to the poles. GPM is an international constellation of satellites,
so what you see right here, it shows all of these different satellites
orbiting in different places. They're from the U.S. and international agencies and they all work
to provide a global picture of rain and snow everywhere around the world every 3 hours.
Now, precipitation gives us a primary way to understand how weather behaves
and how climate changes over time.
And so really the difference between weather and climate, which is important to note,
is that weather is sort of like our mood, how we feel on a day-to-day basis,
whereas climate is like our personality over time.
Sort of like: do we bring an umbrella today or do we bring it this season.
And so what GPM and other NASA satellites are helping to understand
is our global water cycle and precipitation is one of the ways, the key contributors to our reservoir in the sky.
Excellent. Well today, we are going to take a closer look at three kinds of severe weather and their impacts.
First off hurricanes, then floods and landslides, and finally we'll wrap up with snowstorms.
So first let's take a look at hurricanes, something actually near and dear to my heart, because having lived in the
Gulf Coast area for six years, I have had to either hunker down or evacuate for hurricanes before,
but NASA looks at them in a whole new way.
That's right. So hurricanes, they're like a heat engine. You need warm water,
you need some preexisting storms, and some breezes to bring everything together.
Now just so we know, hurricanes and typhoons, and cycloons - they're all the same phenomena, just in different basins.
We actually just finished the Atlantic hurricane season yesterday, November 30,
and we had a pretty light, pretty mild Atlantic hurricane season, and a pretty active Pacific season.
Now, from the vantage point of space, you can see some of these major storms in ways that you can't see on the ground.
The Tropical Rainfall Measuring Mission, or TRMM, which came right before GPM,
has been looking three dimensionally at hurricanes such as this, this is Hurricane Katrina, and it shows layer by layer
through storms, these huge towers, which we call hot towers, and those are convective systems,
convection within hurricanes that show when we might have a storm intensifying and where it might go.
And so TRMM was the first one to look at these storms in 3-D.
Now GPM is actually able to improve upon that, looking at everything from the tropics all the way to high latitudes.
And so what we're able to see, this is a graphic of Hurricane Gonzalo, which affected the Atlantic,
what you are looking at here is heavy precipitation in the reds and pinks and lighter in greens,
and what GPM can see is also the blue, which is the snow and the ice on the top of the storm
and looking at all of those together, really helps us to understand the dynamics of the storm, where it's going.
One of the things that we haven't been able to do as of yet, before GPM, was look at
storms like Hurricane Sandy for example. Now Hurricane Sandy affected the East Coast.
This actually shows wind speeds and it shows the speeds - the red is really, really intense winds - and it shows it moving its way
up the East Coast. Now GPM was just launched in February of this year, and before that, which is when Hurricane Sandy occurred,
we wouldn't have known what the rainfall was like in this storm as it was off the coast.
GPM can really allow us to have the global picture from the tropics all the ways to the poles.
That's fantastic. So while TRMM is a wonderful program, wonderful mission,
it's really limited because it's going around the equatorial region of our planet.
While GPM is showing us the more global, as it says in the name, the more global view.
That's right.