NASA obviously is very focused on what we
can see from space, what we can learn from
space about our own planet.
And so we have a lot of satellites in orbit
that are producing huge amounts of data that
are telling us about how the clouds are changing,
how the sea surface temperatures are changing,
what's going on with ozone, what's going with
aerosols, and all of these things are giving
us a unique view of the planet as it is right
now.
The role of models is to integrate that information,
to synthesize that information with what we
know about physics, what we know about sources
of aerosols, what we know about atmospheric
chemistry, what we know about ocean dynamics,
and then build a picture that allows us to
go from the information that we're seeing
from the satellite to infer things that about
what we think about the whole planet, how
it's changing.
Modelers don't actually have a crystal ball.
There are many, many things that are going
to happen in the future that we can't predict.
There's going to depend on economic development,
technological development, societal development,
all of those things are completely outside
of the ken of a climate modeler like myself.
So what we can do instead is we can do scenarios,
we can ask 'what if' questions.
What if we continue to increase the amount
of carbon dioxide in the atmosphere?
What if we continue to increase the amount
of tropical deforestation?
What if we continue to increase the amount
of air pollution from Asia and from the rest
of the world?
And we can say, ok, well if those things happen,
then these are likely to be the climatic effects.
These are likely the changes in temperatures,
the changes in statistics of heat waves, in
rainfall patterns, and in rainfall intensity.
And we try to put those together and test
them with observations that we've had over
the past when we've got good information from
the satellite record, and even going further
back where we have information from proxy
records that allow us to test our model system,
that we understand what the major drivers
and the effects are.
