Reporter: Well El Nino's finger prints are already on this winters weather forecast,
influencing extreme weather events ranging from tornadoes to blizzards
across the United States and globally.
NASA has been following this El Nino since its development,
showing its striking impacts from space.
Here to talk a little bit more about this and show us what NASA has seen is
Dr. George Huffman at NASA's Goddard Space Flight Center. Thanks for joining us.
Huffman: I'm glad to be with you.
Reporter: So what can you tell us about this years El Nino?
Huffman: This year's El Nino is like many El Ninos.
You have warm water which is formed in the equatorial pacific and
of course its not just the surface but the whole upper layer of the ocean
and it gets really warm and all this heat causes the jet streams to move to the north.
It drives precipitation locally in the Pacific Ocean but also on the west
coast of the US.
Reporter: What kind of environmental changes are we seeing with this El Nino?
Huffman: This El Nino is driving a great deal of precipitation
across the Pacific Ocean and so you have
heavy rain fall in the central pacific
and then dryness to the west.
This extends not only across the pacific but in fact
around the globe and it also extends to the west coast of the US.
Reporter: Will this year's El Nino bring relief in California?
Huffman: The California droughts have built up over several years so its really hard to get relief in a single year.
It is the case that the west coast has been getting excessive precipitation but mostly in
northern California and up in the pacific northwest.
The good news is the snow pack in the Sierras is like a hundred percent of normal for this time of year.
So they should have better water supplies during the summer, but the long term drought remains.
Reporter: Could this year's El Nino turn into a La Nina and if so what would that mean for us?
Huffman: It is the case that strong El Ninos are frequently followed by La Ninas
and if that happens the warm water will be replaced by cold water some time during the summer
and into the fall.
When that happens the typical pattern is that you have
lower rainfall in the central pacific,
lower chance of rainfall on the west coast of the US in the following winter
and an increased chance of hurricanes in the Atlantic Ocean.
Reporter: How does this years El Nino compare to the big one that we had in 1997 and 1998?
Huffman: That's an excellent question.
The 1997/1998 was the last El Nino which was
as strong as the one we are now experiencing,
and the big difference is that the 1997/1998 was more of east pacific,
you see in this graphic it maximizes up against South America,
where as this year it's more of a central pacific
that has some really fundamental changes in the way it drives the
global circulation anomalies that we are seeing this year.
Reporter: Where can we learn more?
Huffman: To learn more you can go to nasa.gov/earth or on Twitter
you can go to @nasaearth