I'm Piers Sellers I'm the Division Director for Earth
Sciences Division here at NASA Goddard Space Flight Center it's
a division of about 1500 people scientist and engineers who
study all aspect of the Earth's system including climate.
Reporter: Now you've been studying the Earth for several
decades now what kind of changes are you seeing?
Piers: Well we are seeing that is NASA and other agencies we're
seeing huge changes in things like the ice sheets now we are
seeing a shrinkage of the Arctic Ocean ice pack reduction of ice
on Greenland we are seeing changes in the vegetation around
the world we are seeing an earlier season to the far north
as the north warms up.
We are seeing changes in the temperature of the atmosphere in
the oceans.
So there are a lot of changes they're all consistent with this
theory of global warm, it's all self-consistent.
Reporter: Is it caused by humans?
Piers: It's absolutely caused by humans.
I'd say that with very high confidence.
It's linked closely with the carbon dioxide that we release
into the atmosphere from fossil fuel burning and a little bit to
methane as well there's bumps and wiggles on the graph from
things like volcanoes and changes of ocean circulation.
But the general trend of the increase in temperature is due
to anthropogenic, that is man made release of CO2.
It's us.
Reporter: 2015 was the warmest year on record 1 degree over
pre-industrial times really doesn't sound like a lot Can you
tell us or the average person what is the significance of that
record?
Why should they care about 1 degree?
Piers: Alright so 2015 was the warmest year on record from
about 1890 from the precise records that we have 2014 was
the next warmest year 2013 was the next warmest year after
that.
Of the last 16 years 15 warmest years have occurred in the last
16 years.
So it's a very strong signal here so the planet is warming
up, now with regards to the point 1 degree centigrade which
is 1.8 Fahrenheit doesn't seem like a lot doesn't seem like a
lot it is a lot when you look on it on the scale of a planet
that's a lot of energy You've heated up the whole planetary
atmosphere or surface atmosphere by 1 degree centigrade that's a
lot of energy it can do a lot, it can melt a lot of ice, it can
change weather and it can change ocean circulations.
Reporter: So even if you're in the middle of the country you
should care about this you're not on the coast so sea level
rise my not effect you but other things will, can you talk about
that?
Piers: Yes, for us humans wondering around 1 degree
centigrade everyday just take it in your stride, it doesnÕt make
any difference to you.
But if it turns out that that 1 degree centigrade on a planetary
scale, on the scale of the whole world changes where the rain
will fall and where it won't, where its going to be hot and
dry, where is going to be a good place to grow food or have water
resources, then it makes a heck of a difference.
Reporter: You said that 2015 was the death of denial, what do you
mean by that?
Piers: I've come to that conclusion after quite a lot of
thought.
The death of denial, the whole business of tiring to pretend
that this global warming is not happening I think the nail is
finally in the coffin and the reason for that is the majority
of the world leaders and their representatives who are meeting
in climate conferences accept the scientific evidence as the
basis for trying to put together policy.
So when you point to the big stack of documents scientist put
together that says you should not try to get to much warmer
then we are now, 2 degrees centigrade is the limit from
pre-industrial temperatures we get policy makers buying into
that I think that is the death of denial.
People of embracing science and the reality of the message.
Reporter: You've been very vocal and passionate about talking
about climate change, what is the main message you want people
to understand?
Piers: A couple of messages, one is that it's real and can't be
avoided, there will be changes and the other thing is this is
not a hopeless case by any means.
We can get ourselves out of trouble, it will take
significant effort and application of technology and
some policy investments but it's by no means hopeless at all.
There is no reason that our future shouldn't be better then
our past.
So I'm optimistic as long as we get on with it.
Reporter: What makes you so optimistic that we can tackle
this crisis?
Piers: I think there a number of reasons to be cheerful.
When ever there has been a sever crisis to society, in particular
in the past 100 years, you've seen eventually a pretty good
response by policy makers, industrialist, technologist,
inventors, all smart people, eventually they line up and work
together.
World War 2 is a classic example; technology was advanced
very rapidly to deal with a threat to the world order and we
triumphed if you like so I think there are reasons to be
optimistic.
Humans generally fight their way out of trouble.
Reporter: What type of technological advances do we
need to, if not solve this crisis at least try to fix it?
Piers: The technical answers are fairly straightforward and
they're obtainable even with current technology so moving
from a carbon based economy to something else is going to
require, it could happen very gradually if we didn't do much
about it, with the proper investments and incentives you
could do this quite quickly.
Move over to new sources of energy, solar, nuclear, wind,
and particularly electrification of the transport system.
I'm convinced that in 10-15 years we'll all be driving
around in little electric cars, very low impact.
So what is interesting about all this is we can achieve the goal
of reducing carbon emissions without putting a huge ding in
people's quality of life I don't see this one leads to the other.
I think people can continue to enjoy interesting, comfortable
lives with the new technology and we lower our carbon
footprint.
Reporter: What do you say to people who say, we give up,
we're to far gone to do anything about this?
Piers: That's totally defeatist.
That's totally defeatist and that's not useful to anybody.
So now we are in a tricky position that is humanity is in
a tricky position now's the time to start thinking.
Now's the time to really start working on solutions and there
are many solutions out there.
There's not a single solution, there are many solutions that we
have to work on.
It's all doable.
Reporter: Let me circle back a little bit.
Talk about your work here and talking about climate modeling
it's very challenging, lot of factors involved, what insight
of NASA's effort accomplished with these models and what
challenges still remain?
Piers: NASA's made a huge contribution to the whole
business of climate modeling, especially NASA Goddard Space
Flight Center.
So there are various tribes of scientist involved here.
There's the tribe that actually makes these climate models on
the super computers, test them, run them, and look at the
output.
But a model without verification is pretty much useless so we
have another tribe of people who take satellite observations and
analyze other types of observations who provides the
constant checks on the modelist so the modelist and observers
are always talking with each other and over the last 30 years
that I've been involved in the business I've seen tremendous
progress in the capability and the credibility of these models
it's been night and day.
Reporter: Can you talk about the changes since you've been here
at Goddard?
What is the science that's changed that we've learned?
Piers: The change that I've seen for myself when I arrived here
at NASA Goddard in 1982 as a postdoc straight off the boat
from London pretty much; we had Landsat, we had some
meteorological satellites, and the French had a satellite
called SPOT that was sort of like Landsat.
That was about it.
That was really about it and it was very difficult to do much
earth science with that little fleet.
Come to the end of 1990's we launched this huge constellation
of Earth observing satellites and that was also supported by
recruitment a bunch of scientist to look at the data.
So there's been an absolute revolution in the last 20 years
I mean really a science revolution in our understanding
of the Earth.
Its been going from very primitive models and a very
primitive understanding to a very detailed, verifiable, see
it everyday, model it everyday capability.
It's been an enormous jump in progress and I feel myself very
lucky to have seen it from the beginning to where we are now.
It's been really exciting ride.
Reporter: Why is it important for NASA study the Earth from
space?
Piers: Well NASA has found that orbit is the exact the best spot
from which to observe the Earth.
The views you get from orbit, here's me actually outside the
ship looking back at the Earth, are very powerful.
You can see thousands of miles in every direction, you're going
around the Earth at 5 miles a second so you can go around the
whole world and map the whole world in a day using a
satellite.
So the combination of being able to see the whole world,
wall-to-wall, everyday with the same instrument is tremendously
powerful scientifically and it's absolutely the cheapest, best
way to study the Earth.
Reporter: So you are one of a handful of people to actually
see the Earth from space, can you talk a little bit about what
that experience was like?
Piers: For me personally seeing the Earth from space was very
revealing and beautiful all at the same time.
It's beautiful as it would be for about anybody just to see
the planet from above, the curve of the Earth, to be moving
around this great big blue ball where we all live, it's
incredibly beautiful.
But as a scientist all the things that I've studied in
theory and in the laboratory and simulations, to see them for
real from orbit, like a whole hurricane or ice packs or forest
or mountains to see it all from a single glance, it put flesh on
the science bones if you'd like for me.
It made if real.
You know one of the things that came out of this is I'm much
fonder of the Earth now having left it and looked back at it.
It's like leaving home, I'm much fonder of it now.
My name is Piers Sellers, I'm a climate scientist here at NASA's
Goddard Space Flight Center and a former astronaut.
Reporter: You were in space 3 times, how did looking down at
the Earth change your perception of Earth, or did it?
Did it seem more fragile looking at it?
Piers: Looking at the Earth from orbit, particularly looking at
the horizon did bring to mind how thin the atmosphere is.
It's like an onionskin around this great big ball
of the Earth.
It's very very thin.
So that really brought home to me how thin of volume of air
that we are all sharing and breathing, polluting if you
like, and how easily it's affected by what we do.
That brought it right home.
Reporter: Did it change your passion for wanting to get the
message out that climate change is happening and we need to
address it?
Piers: Not at all because I was passionate about it before I
went so maybe a little bit more motivated, that's all.
Reporter: What is your proudest moment working as a NASA
Scientist?
Piers: I can't pick out a single great moment; to be honest it's
amazing to just see the session of triumphs particularly in the
science over the last 20 years one building on another so it's
been a terrific ride.
Almost everyday someone will walk into my office and tell me
something new, some insight that is exciting.
So it's been a continuous rush.
Reporter: Now you said in your New York Times article that you
wanted to come straight back to work, why do you love what you
do as much as you do?
Piers: I was accused of several people of having a chronic lack
of imagination, couldn't think of anything better to do then
come back to work.
But the work is really interesting.
I mean the reason I got into the science in the first place
because it's fascinating but it's really important too.
I mean it's really really important, for everybody,
for all 7 billion of us.
So I feel not only this is how I'd like to spend my time but
also kind of a responsibility.
NASA spent 30 years training me if you like to do this job so I
feel some responsibility to keep doing it.
Reporter: You talk to kids a lot, what do you tell kids about
where we are and climate change?
What are your hopes for the next generation?
Piers: Oh, upbeat for the most part.
If you take people in their teens they are perfectly capable
of understanding the changes that are going on and that they
will have to deal with them more then people like me at my age
obviously they get to inherit the Earth that we leave them.
I try to tell them that these problems are being looked at,
they are being addressed, not as fast as we'd probably like right
now and it will be a continuing work ready to solve a problem
and some of it will be up to them.
You know, them seem to absorb it ok.
Reporter: You learned to fly at a young age,
what inspired youto do that?
To want to learn how to fly and what inspired you to
become an astronaut?
Piers: I can't imagine why anybody wouldn't want to learn
how to fly but that's my mindset.
I was at school and they had the Royal Air Force, I was in the
United Kingdom, the Royal Air Force had this great program
where they teach you to fly gliders solo at 16 then fly
powered aircraft at 17.
I've been flying ever since then.
So interest in fly and interest in space went hand in hand,
it's all the same community of people how do this.
So I've always been drawn to it and still enjoy it today.
I love to fly.
Reporter: What about studying earth science, what prompted you
to pick that field?
Piers: I really started to get interested in earth science when
there was this gap that I found myself able to fill and that was
the gap between biology and climate so I started out as a
biologist and then moved over to climate studies and realized
that there was quite a strong link to the way the whole
Earth's biosphere works and its impacts on climate were strong
so not many people were looking at that time so it was an
opportunity to investigate something new and I got sucked
all the way in never managed to get out again.
Its been a lot of fun.
Reporter: You've been very optimistic about climate change,
what can we as humans do adapt?
Piers: Well if you look at history have done a great job of
adapting to changing circumstances and actually
improving their lot in the process.
You go all the way back to transition from being a bunch of
very sparse, hunter-gatherers to becoming an agricultural society
and that was a huge change.
It allowed the population to increase massively; it allowed
cities and the growth of civilization so things go better
for humanity really quickly.
Then going from an agrarian culture to an industrial culture
in the 1750's another big step change, another big improvement.
Now we have the modern world, the modern world is marvelous
compared to being a caveman and I'd think you'd have to agree,
you know?
Certainly a lot cleaner.
Now we got another change facing us, it's a relatively
small change.
The way we use energy and the way we store energy, the way we
use energy, and so that's a relatively minor change in the
great scheme of things but looking back at history the way
we've copped with previous challenges, I don't see this as
being impossible at all.
Reporter: So it's just another step we have to take?
Piers: It's just another step we have to take as humans and we've
done it before.
Reporter: Why are you so passionate about this issue?
Piers: Well I've very interested in the science for one and you
know the whole time I've been working at NASA I've been amazed
at how the gains we've made through all the technology
particularly the NASA has thrown into the mix.
So it's really interesting but I think on a broader level
responsibility as a scientist so I see things are happening I
understand some idea about how the future is going to develop
so I feel some responsibility to society to report that to the
public and policy makers to make it crystal clear to people what
is going on.
Reporter: So how has your cancer diagnosis changed your outlook
on climate change issue?
Piers: Well for me personally realizing I have rather less
time to deal with this, trying to get more done in the time
available.
So I'm actually working at 20 times the normal rate and
it's still fun.
It's just concentrating my efforts on what's more important
I guess.
Reporter: Talk a little bit about your childhood.
Why did you want to be an astronaut?
Piers: Well I was lucky enough to grow up during the 1960's
during the race to the moon so I saw the whole thing,
the Russians, the Americans you know, trying to get to the
moon first.
It was tremendously exciting.
I mean everything, the lunar landing, Apollo 13 the rescue,
all of that stuff was just wonderful and it got me
interested in science, it got me interested in aviation, learning
to fly and it got me interested in NASA.
So I thought the whole show was put on just for me to motivate
me in my career.
I found out that wasn't true but it might as well been.
Reporter: You've talked about the changes you've seen since
you were born.
Where do you think we will be in 50 years?
Piers: In 50 year's time, I think we will probably be a
little bit warmer then the 2 degrees centigrade we set
ourselves, hopefully not too much.
I think there will be a massive change in the way people live.
I'm hoping that the bottom third of the population of the world,
who are very poor right now, will be a lot less poor.
We'll be able to transfer technology and wealth to them
to make their lives better.
It could be a much better world and it should be a much better
world in 50 years time.