You're

almost right

thank you Chris Dodd certainly
a pleasure to be here.

I'd like to start off by asking
you a few questions How many

have seen El Gore's movie.

Most people.

How many people have some familiarity
with the Intergovernmental Panel

on Climate Change or the I.P.C.C.
fourth assessment report.

OK if you give us.

How many people have come across any
of these books or read any of them.

OK a few How many people are confused
by the issue of global climate change.

OK how many people feel
comfortable with the I.P.C.C.

report and have confidence in it.

OK how many people would put themselves
squarely in the skeptics camp.

OK one brave soul raising their hand.

OK good.

OK I like to know what we know
what I'm starting from I would

like to describe to you a little bit
about the process related to the I.P.C.C.

the Intergovernmental Panel
on Climate Change and

why the scientific community has
confidence in their findings.

The I.P.C.C. was formed in one
nine hundred eighty eight by the.

United Nations Environmental Program and
the World Meteorological Organization.

And it was formed to provide policy
relevant assessments of the science.

And the assessment is based on what
is in the Perry view literature.

And there are three main parts
to the I.P.C.C. reports.

And today I'm going to focus on
the findings from working group one

on physical climate change.

Now the working group one report again
that this was something that took

four years.

Started in two thousand and three had
one hundred fifty two authors that were

carefully selected from the international
scientific community had over

four hundred additional contributors and
six hundred expert reviewers

the document is a thousand pages and
has five thousand literature.

References and.

The process is has evolved over

a period of several decades and
it's been refined each

time in terms of making it more objective
more comprehensive and more complete.

And I'd like to go through
the sequence of the four I.P.C.C.

assessments and the main conclusions
that has been drawn from them.

The first I.P.C.C.

report in one nine hundred ninety
conducted a broad overview of climate

change science and discussed the
uncertainties and evidence for warming.

In one thousand nine
hundred five the I.P.C.C.

made a statement stating
that the balance of evidence

suggests discernible human
influence on global climate.

In two thousand and one the I.P.C.C.

assessment said most of the warming
of the past fifty years is likely.

Which means greater than sixty six percent
to be attributable to human activities.

The most recent I.P.C.C.
report in two thousand and seven.

Stated that warming is unequivocal and
most of the warming of the past

fifty years is very likely
are greater than ninety percent.

Due to increases in greenhouse gases.

The I.P.C.C.
group working on working group one head

of the authors seventy
five percent of them

were different from the group in the
I.P.C.C. two thousand and one report so

this is not the same group of scientists
continuing to say the same thing but it's.

There is a continuing group of
scientists involved in this but

the vast majority of them
change with each report.

So what I'm going to start off by doing is

give you you know summarize the evidence
in support of this I.P.C.C.

statement that the warming is unequivocal
that most of the warming of the past

fifty years is very likely due to
increases in greenhouse gases.

OK for us in terms of the earth's climate
there are a variety of factors that

influence that different time scales.

We have extra terrestrial factors
everything from solar output and

solar cycles earth sun geometry that
gives us the ice ages that varies.

Tens to hundreds of thousands
of years interstellar dust.

We have within the Earth itself.

We have the longer term for
seeing plate tectonics and

continental drift shorter term variations
associated with volcanic emissions and

other things and
also changes in atmospheric composition.

And as these changes in atmospheric
composition that can influence climate

timescales of decades to a century
which are of particular interest

to the most recent global warming.

Now the industrial revolution has changed
the composition of the atmosphere

particularly carbon dioxide methane and
nitrous oxide concentrations all of which

have infrared image in the infrared
part of the spectra and

therefore contribute to
the atmosphere greenhouse.

Concentrations.

And you see you see the data that we have

on carbon dioxide methane and nitrous
oxide Khans some traces going back.

Several thousand years show
that the recent spike.

OK since one nine hundred seventy S.

certainly unprecedented
during this period.

Now if you go even farther back.

You can't get both OK if
you go even farther back.

In geologic time and
look at the ice cores and

we're talking about five
hundred thousand years.

You see substantial variations with
the you know the ice ages basically where

the blue is temperature and the red is
atmospheric carbon dioxide concentration

and you see them pretty much going
in lockstep so as the orbital

the Earth's orbit variations in the tilt
of the axis contribute to these ice

ages the planet warms and
then Theo to respond to this forcing in

terms of the amount of carbon dioxide that
the ocean can take up and also influences.

Carbon dioxide through
ecosystem productivity.

OK So we see the last ice age here now.

OK.

Right.

So if you look at the most recent
last two hundred years or so

we've seen a substantial spike in
atmospheric carbon dioxide which

is associated by the burning of fossil
fuels by human and all of a sudden worth.

We're putting an additional four
saying OK on the climate system

whereas before C O two was responding.

OK To the orbital variations and
the resulting ice ages.

In the last two hundred years or
so we are now for.

Seeing.

The composition of the atmosphere
through increased carbon dioxide.

We see a substantial increase.

OK We're now at about three hundred
eighty three parts per million.

OK.
Compared to a more natural peak level

of about two hundred eighty.

OK.

That you see in the interglacial period.

So basically what we're
doing is we're short

by burning fossil fuels we've short
circuited the global carbon cycle.

OK So when hydrocarbons are burnt.

He has added to the atmosphere.

We're basically accessing heat laid down
in photosynthesis millions of years ago.

And so what this does is enhanced
the natural greenhouse effect

of carbon dioxide itself.

Those not have an enormous greenhouse
effect because its concentration is

relatively small but what the small
amount of warming directly caused

by carbon dioxide in
the atmosphere results in more

evaporation from the Earth's ocean and we
get more water vapor in the atmosphere and

this amplifies the warming
from carbon dioxide.

So it's the combination
of greenhouse gas and

water vapor that are giving us
the temperature increase a substantial

portion of the temperature increase
that we're seeing and it's triggered by

the greenhouse gas carbon dioxide
primarily but to a lesser extent.

Methane and I just oxide.

We also have.

Better and
longer satellite data about the sun and

then this shows the total solar
radiance since one thousand nine

hundred ninety eight and
we see the eleven year solar cycles.

And we don't see any trend in solar
irradiance over the last three decades and

right now we're actually at pretty
much at the bottom of the solar cycle.

But there's no true.

And in this data and
the solar forcing is really only

you know less than a tenth of a percent in
terms of the variation over a solar cycle.

So this is really a small amplitude.

Forcing on the global climate relative
to the increase in the greenhouse gases.

So if so if we look at over
the twentieth century the human and

natural drivers of the climate change
in terms of atmospheric composition.

We see in terms of the units
here radiative forcing watts

per meter squared we see that the biggest
contributor is carbon dioxide.

Then we have methane nitric oxide and and

Hale carbons we have some
tropospheric ozone also contributing.

On the cooling side of the balance we have
aerosol both from volcanic aerosol and

pollution aerosol actually have a cooling
effect both through the direct effect and

also through influencing clouds.

And so
if you look at the contribution the sun

is really much smaller in magnitude
to any of these other factors that.

Are contributing to
the earth's radiation balance.

Now the thing about carbon dioxide is that
once you put into the atmosphere it lives

more than one hundred years
in the atmosphere and

therefore expects climate over a long
time scales some of these other things.

Aerosol tends to be precipitated out or

settle out and methane gets involved
in various chemical reactions but

carbon dioxide is a fairly long lived
gas with a so it's effects accumulate.

OK All these little tricks I didn't
even know were on my slides.

OK one test of our ideas about

how the climate responds to
a rapid change in atmospheric

composition comes from when we have a big
ball can a corruption and here we see.

Mount Pinatubo which erupted
around one nine hundred ninety

and a rapid global cooling
resulted from this and this.

Change has had substantial feedbacks in
the climate system change the temperature

in the water vapor etc and then bounce
back after a couple of years and

so we can test our understanding
of how the climate responds to.

Forcing to atmospheric composition
through some of the short lived events

like volcanoes.

OK In terms of the warming that we've seen
over the last hundred fifty years and

we have fairly good historical records.

We've seen rising atmospheric temperature.

Almost two degrees Fahrenheit or
one degree centigrade.

We've seen rising sea level.

A couple of centimeters over
the last hundred years and

we've also seen a decrease in
Northern Hemisphere snow cover.

Also probably the most dramatic change

in the climate that reflects warming
is the decrease in summertime.

Arctic sea ice where we've seen.

An average of a four
percent decrease per decade

since about one thousand seventy eight.

We saw a dramatic decrease
in the summertime

sea ice in the summer of two thousand and
seven it bounced

back a little bit in two thousand and
eight but it remains very low.

Now the Arctic was also warm during the
period of about one thousand twenty five

to nine hundred forty one.

We also saw a reduce ice extent but
that was before we had satellite so

we don't exactly know the details of
exactly what the ice aerial extent but

the extent of the that was believed to be.

Natural internal variability
associated with.

The North Atlantic.

Nick and arctic oscillation type
modes of climate variability and

the warmth was not global
during that period.

We also look and you'll hear more about
this at the next talk on this subject

by Dr Kim Cobb on paleoclimate.

We also want to look past backwards
before the historical record.

And we have some decent proxy wreckers of

temperature change back to
about seven hundred A.D..

These are taken at at locations
all over the earth and

there's not as much sampling
as you would like and

they come from different sources
corals tree rings boreholes ice cores.

But basically the conclusion that you
can draw from this is that the latter

half of the twentieth century is
warmer than anything you've seen.

OK And
in the last about fifteen hundred years.

Again trying to do the statistical
sampling interpretation

of all these different types of of records
is very much a work in progress and

you will hear more about this from Kim.

At the next meeting.

The other piece of evidence or tool that
we use I mean we have theory we have

observations but
we also use climate models.

And climate models help us

interpret the physical processes going
on in the warming and climate models.

These are numerical models that represent
prophecies in the atmosphere land surface

the ocean.

And the ice.

Thousands of good points.

And these models are based
on the laws of physics.

They basically solve the navi or
Stokes Equations for the fluid flow in

the atmosphere in the ocean and all sorts
of other physical processes at each grid

point the clouds the radiation
the priest the potato and sea ice etc.

And the resolution of these models.

Are about one hundred kilometers in her.

As Onil extent.

Two maybe three or
even four hundred kilometers.

And in the I.P.C.C.
twenty three different models.

Were used in the assessment representing
slightly different resolutions different

treatments of the various physical
processes different solutions.

Of the Navier Stokes Equations etc.

So one of the most important
applications of these climate

models is in the so-called
attribution studies.

And these studies ask
whether the observed.

Changes in temperature or whatever are
consistent with the expected responses to

the forcings and also inconsistent
with alternative explanations.

Now if you first look
at the bottom diagram.

OK down here.

Again the black curves see observed
global temperature record.

And the blue one is

the average the dark blue one is
the average of the twenty three.

Climate model simulations

that are forced only with natural forcing
like volcanoes and solar variability.

OK And we see that.

There's some agreement up to
about nine hundred sixty.

But then we see a series of volcanoes
that really have a cooling effect.

OK In terms of natural forcing That's
clearly not able to explain this

observed temperature increase by natural
forcing from the sun or the volcanoes.

Now if you combine the anthropogenic and

natural forcings where you add
the greenhouse gases and the aerosols.

Then we see that we're able to
explain reasonably well and

all these different individual lines.

Our lives from the individual
model runs and say the red line.

Represents the average of these.

OK.

So how confident are we.

Of our attribution of twentieth
century global warming.

Well I like to use to.

Analogies the first one
is a puzzle on the Elegy.

While several of the pieces are not yet
in place.

We have confidence that we know
what the overall picture is.

The second and

they argued that I like to use
a so-called three legged stool analogy.

And the three legs of the stool
are observations models and theory.

So the observations models and
theory are in general agreement

pointing in the same direction and
therefore the stool is able to stand.

Well everyone wants to know
what's going to happen next.

OK in the future.

And the future climate depends on
the future greenhouse gas emissions.

Now.

So a bunch of complicated social economic
scenario is were established to figure out

how much C O two emissions
might be emitted in the future.

And there's a couple of different
scenarios one is the so-called commitment

run which means that we

keep it steady at the two carbon
dioxide at steady at the two thousand.

Year two thousand amounts and then we have
a business as usual one that just keeps

going up as population increases and
economic development goes on and

cetera and increases the need for.

Energy and
it's mainly supplied by fossil fuels.

And then there are several other

ones where some mitigation is taken place
where we eventually start to decrease.

The amount of carbon dioxide emissions.

So what are the model simulations
say once you force them with these

different scenarios of greenhouse gas.

Well we start with the so-called commit
scenario where we commit to leaving at

the carbon dioxide at the same as it was
in year two thousand and we see that even

with the commit scenario we're looking at
about a one degree Fahrenheit increase

by the year twenty one hundred and this
is because there's still a lot of a lot.

The warming from the C O two.

We've already put in the atmosphere
hasn't yet been realised.

And then for the more extreme scenario
which is this sort of business as usual.

You see we're looking at an average
of six degrees Fahrenheit.

And these numbers over
here represent the sort

of equilibrium carbon dioxide associate
concentration eight fifty parts per

million associated with
each of these scenarios.

OK so how do we interpret this you

know how confident are we have the climate
model projections for the next century.

Well certainties that sea level rise in
temperature increases are inevitable but

there are certainly uncertainties in terms
of the actual magnitude of the warming

the magnitude of the climate forcing
is uncertain because we don't really

know what the future greenhouse
gas emissions are going to be we

don't know exactly what the future
volcanic activity is going to be.

And it's conceivable that there
are some potential surprises related to

future solar activity.

And also the climate models
aren't perfect either.

There are some uncertainties
in the climate models.

And there's also the prospect for
a block abrupt climate change and

we don't quite know if our models
would handle those correctly.

The other issue in terms

of figuring out how to
use these climate model

simulations is that the average warming
for some of these scenarios really.

If you only look at the average
warming I think you're missing a lot

of the information.

Again out of these twenty or so.

Well actually seventeen that did
the twenty first century runs.

Each of them ran a minimum of
five per term runs of each model.

Associated with different
initial conditions or

slightly different versions of the model
to assess a range of possible outcomes.

So you can see that for
each each one of these.

Scenarios you have a range almost a factor
of two difference in terms of what you

might get and so there's really a P.D.F.
you know even for

each scenario amongst the different models
of the different perturb runs in terms of

something on the low side and
something on the high side and then.

You know some average with
the greatest probability and.

If you're only looking at the mean.

You're missing some of the potential high
risk that could occur on the high end then

you're also missing the probability that
things might not be as bad as the mean so

is I think it's important
to look at the entire

distribution method to get out of this.

And the other thing related to
the distribution is even if you.

We knew exactly what the average
increase was going to be

real temperature is really a distribution.

You know of cold and hot.

You know from year to year and
place to place.

And if you warm.

You know you you move the distribution
to the warm and a little bit but

you have that the real significance of
this is what's happening on the tail of

the distribution in terms of
the extremes the extreme weather the.

Extreme plug events the extreme hot
weather the extreme hurricane this

type of things.

So it's very important to look at
the distribution of what's going on at

the extremes because the average
temperature increase for the most part.

People could adapt to in a given
location but it's the extremes.

The other issue to worry about is
the so-called tipping points again.

Tipping points is a word that's used
all over the place at this point and

Jim Hansen has introduced it in the
context of the climate change issue and

the term tipping point really comes from
epidemiology related to the point in time

when a disease suddenly accelerates
to becoming an active epidemic.

OK So the question is Are there points
in the ball being climate system.

When the change becomes irreversible.

Possible climate tipping points that have
been discussed and the one that I put

in bold is the one that I think is the
main one to worry about in this is really

the melting of land ice particularly
the West Antarctic Ice Sheet and

secondarily Greenland the process of
melting is essentially irreversible.

You know the timescales of.

Hundreds to thousands of years.

Which would result in inundation
destruction of habitats

now Greenland would take hundreds of
thousands of years to completely melt but

the West Antarctic Ice Sheet
could melt on time scales.

That are much shorter one to two hundred
years and this is fairly unstable and

if the West Antarctic ice
sheet were to melt it would be

increased global sea level by twenty feet.

To me that's the big one the others.

Are non-trivial but I regard that
one as a real tipping point and

that's the main one that I worry about.

The issue of sea level rise the I.P.C.C.
indicates that it's likely greater than

sixty six percent an increase
of one to two feet.

OK By the year twenty one hundred this
does not include any accelerated or

catastrophic melting of ice sheets.

Now more recent estimates than
the I.P.C.C. suggests that

a one point four meter sea level rise
by twenty one hundred is plausible.

And if you look at what this would
mean in terms of the Gulf Coast

the red would be about
one point five meters so

a big chunk of South Florida and southern
Louisiana would be below sea level.

And of course the West Antarctic Ice Sheet
as I mentioned if that were to completely

happen which could conceivably happen on
a time scale of one to two hundred years.

We're looking at a twenty
feet increase which would be.

I mean New York City.

I mean on the whole all the cities
on the eastern seaboard.

OK well.

About projections of
precipitation changes.

OK Well we have on the left which are time
and summer time but the main thing

is that precipitation increases sort of in
the blue is very likely in high latitudes.

And decreases are likely in
the subtropical latitudes

the regions with the hatch means that

two thirds of the models runs were in
agreement on the sign of the change.

So these reasons mean that there is
relatively greater uncertainty and

even the sign of the precipitation change
and you see that the Southeast US and.

Is mostly in this region where there's
no obvious change and there's a lot

of discrepancies in the model between
what the average precipitation would be.

When trying to interpret what might be
going on at a local like in Georgia or

in the Southeast US.

We have to understand the limitations
of these global climate models.

If we look first here with
the global mean temperature and

some different climate models simulations
you see that the climate models

do a pretty good job at capturing
the global temperature change.

If you just look at the continental U.S.

you see that the climate models pretty
much capture what's going on in

the continental U.S. If you then define
a smaller region at the southeast U.S.

you see that the climate models don't
capture the observations in the south

southeast US is one of the few places
where there is actually been a slight

global cooling trend over
the last hundred years.

OK So well why can't we rely on
the climate models at regional SCALES Well

the resolution of the model is too coarse
you know to really capture much detail and

also the models don't really get
the year to year variations of.

You know and some of these big natural
oscillations correctly in terms of their

timing and these have very large
signals in various regions.

So again.

You can't really rely on these
global climate model simulations to

look at very small scales.

OK.

Let's take a look at least
in the continental U.S.

what the models do say again
most of the warming projected

warming is in the higher latitudes we
see that down in the Southeast US.

Again the warming is projected to be
as small as anywhere in the U.S. OK.

In terms of the changes in
frequency of the heat waves

remember it's really that stuff that's
on the tail of the distribution.

We're looking at a lot more
sort of record breaking.

Hot days.

And so those sort of the one
in twenty year hot day

by twenty one hundred that in our
current climate would be would occur.

One in every three years.

OK And the peak temperature
that the maximum temperature

could increase by like six degrees that
we might see anything very extreme day.

In terms of precipitation.

Again it looks like.

Really.
Right.

Not much of a change for the Southeast US
again the climate model results are fairly

uncertain the course resolution ones but
it looks like on average there

wouldn't be much of a change in terms
of southeast precept attention.

Now and are you trying to get at what
might be happening on a regional

scale we people have used the I.P.C.C.

sonority or
runs to force regional downscaling

models to get a better representation of
what's going on at the regional scale and

these are the finest mesh
is really a few kilometers.

And so.

The interesting thing that has come out
of these runs as Although the average

rainfall in the southeast wasn't changing.

We see more heavy rain days and

more droughts So even though the averages
the same more droughts more floods.

What we can expect.

OK so the consequences and
our vulnerabilities to this climate change

are fairly complex everything from
agriculture forests water coastal

resources ecosystems human health
communities Energy Commerce.

But what are we supposed
to do with all this.

You know information you know
how do we sort through it and

how do we make decisions about what we
should do in response to this threat.

Well there's two types of actions two to
dealing with global climate change and.

The first one is adaptation which is
essentially local where what you do is you

try to minimize OK your vulnerabilities
and impacts you know building levees.

You know things like that and
the other one is mitigation

where we actually reduce the greenhouse
gases in the atmosphere and

that has to be global because just one
city or one country reducing greenhouse

gases isn't really going to
affect the global carbon dioxide.

OK So there's two types adaptation and
mitigation.

Now.

If we use the southeast U.S.
Evan example and

try to figure out what what what we should
do one of the challenges in terms of

adaptation one of the challenges to doing
anything sensible in terms of adaptation

has been that the U.S. National Assessment
of climate change impacts.

Which was written in one thousand nine
hundred eighty is outdated incomplete.

The Bush admin astray.

Suppressed distorted and
discredited the report and

by a weighted federal law by not doing
a follow on study every four years and

go back the unintended
consequence of this is by not

providing the information needed for
adaptation.

There's now a mad panic
to focus on mitigation so

I think the unintended consequence of
this was by slowing the adaptation down.

Now there's more pressure on
the mitigation side of this.

OK Take a look at the local
warming in Georgia.

What are the what's been happening so far
and what are the potential consequences.

Well things that will look at our sea
level rise heat waves droughts and floods

hurricanes air quality infectious diseases
agriculture forest fisheries and wildlife.

So the impacts in these areas have
potentially impact all sectors of

society economy ecosystems public
health and safety and quality of life.

The impacts of drought.

We've already seen we've had a wonderful.

Little case study here
in these last few years.

We've seen the mandatory
water use restrictions

the threat of running out of water.

The lack of reliable water supply will
hurt industry economic development

property development.

It impacts energy generation
hydro power power plant

cooling going if we're looking at putting
nuclear power plants in the Southeast US

that are going to place even more demands
on our water resources and that's

something that needs to be considered
in the context of our water resources.

Put stress on forests and
wildfires stress on agriculture and

livestock stress on landscape
tourism recreation industries

stress on river ecosystems and the
estimated cost in two thousand and seven.

Of the north Georgia drought.

Was one point three billion dollars and
I haven't seen a later tally than that.

Now.

Also looking at the prospect of more
floods not just due to hurricanes but

also just due to heavier rainfall offense.

Again the immediate impacts
are property damage injuries and death.

It's a variety of health issues including
infectious diseases breeding grounds for.

Mosquitoes exposure to toxins pox owns and
some of the key water quality issues.

Particular in the southeast U.S. is.

Flood water tainted with
agricultural waste.

The chicken farms and
the hog farms they have the.

Waste retention pools that when they
get flooded all of the pollution and

it's a huge problem in North Carolina and

it's a growing problem with
the chicken farms particular in.

In Georgia.

And the recent example of flood damage
was Hurricane Francis in two thousand and

four cause forty million dollars
in Atlanta loan from flooding.

The impact on forests are largely
associated with the bark beetles.

Which are very dependent on temperature.

As it gets warmer the drought
the bark beetles thrive.

With a drought.

They have lots to chomp on in terms of you
know the forests lose resistance under

drought conditions to the bark beetles and
then they're more susceptible to forest

fires and the forest fires and contribute
to respiratory disease and we've seen.

We had a big forest fire
a couple years ago in Atlanta.

Other impacts include warmer temperatures

where which results in the worst
summertime air quality.

The issue of infected diseases
particularly the vector borne

ones from mosquitoes such as then
yellow fever and West Nile virus.

And also complex economic impacts
Atlanta looks less desirable for

economic development.

If there are perceived to
be water shortages and

increasingly poor air quality.

The issue of hurricanes is a big one for
the Southeast US And

here's the summary findings
from the I.P.C.C..

So there's observational evidence for
an increase of an intense

tropical cyclone in the North Atlantic
since about one nine hundred seventy.

Which correlates with increases of
tropical sea surface temperature and

it's likely that future tropical
cyclones will become more intense

larger peak wind speeds and
more heavy precipitation so

stated with ongoing increases in
tropical sea surface temperatures.

This was a paper published by my colleague
Peter Webster and myself in two thousand

and five back to few weeks after
Hurricane Katrina struck where we found.

The main result here is essentially

a doubling in the percent of Category
four and five hurricanes globally.

Which was obviously of great sensitivity
in the U.S. right after Hurricane Katrina.

This was literally published
right between Katrina and Rita.

Even though the number.

The total number of global hurricanes
is not increasing we're seeing more and

more category four and five a great deal
of controversy surrounding this paper but

it's essentially.

Held up in terms of this seems
to be the main signal in terms

of the hurricanes is this increase in
the percentage of Category four and five.

Whether it's a doubling or
an increase of fifty percent or so

the scientists are still arguing that one
but that seems to be the main signal.

Hurricanes aren't increasing worldwide but
in the North Atlantic.

OK we do see an increase in the over
the last thirty years in terms of.

Total tropical cyclones in
the North Atlantic that

seems to be related to
sea surface temperature.

Again this is hotly debated by to
what extent this is associated with

natural variability global warming
deficiencies in the data or

whatever but it is there is some
apparent increase in the number.

In the Atlantic.

Because well.

Well where do these strike.

Well Florida gets the most
North Carolina the second.

OK And then the northern Gulf Coast.

The third.

Coast of Georgia hasn't been
struck in the last fifty years but

in the eight hundred ninety S.
it was struck by three major hurricanes.

The risk to coastal Georgia and there
were three major land falls in the eight

hundred ninety S. but
none since one thousand nine hundred but

the real big issue is there's a potential
for a big storm surge because the shelf

continental shelf over
here is very shallow and

also the barrier islands are extra
risk associated with sea level rise.

Now it's not just the coasts it's
vulnerable for those of you who are here

in two thousand and four we had four
hurricanes pass through Georgia.

I've been was particularly disturbed
destructive it produced a bunch of

tornadoes that hit in Georgia.

OK it produced twenty five tornadoes in
Georgia alone resulting in two deaths and

ten injuries.

And rainfall in excess
of five to ten inch.

Inches and
destroyed fifty percent of the pecan and

fifteen percent of
the cotton crop in Georgia.

Property damage estimated
at sixty eight million so.

We can.

So we're vulnerable to
these storms coming up.

Through the Gulf as well as
the ones who are in the coast.

In terms of adaptation strategies for
the coast.

A variety of strategies that you can use
land use coastal engineering building

codes wetlands preservations
forest preservation.

But Georgia hasn't been serious
because we haven't been struck

in about one hundred years but
we're going to get hit.

Sooner or later.

I'm going back to this one.

Again this is a global issue mitigation
and it's one for national policy but

the adaptation issues.

And what local governments and
state governments and

regional governments do to reduce or.

Bonar abilities and
also how they deal with a medication.

Activity is a complex
intersection of engineering

politics ethics economics and
whatever is very difficult.

To decide what to do most states in
the US have some sort of a climate

action plan George is one of the few
that does not have anything at all.

And again some of the challenges to
Regional Climate Change Assessment

mitigation and adaptation.

A lot of people who don't
want to deal with the issue.

You know say well there is uncertainty in
climate change projections no question

about that but that doesn't
mean that the risk isn't there.

There's a lack of understanding of how to
apply this knowledge to support decision

making and risk analyses.

And the impacts of regional climate change
and local vulnerabilities have been

an adequately studied and local and
regional mitigation and adaptation

strategies are further complicated by
political cultural and economic issues.

OK And so
that that you know it happens when you.

You know it's only going to happen when
there's political will in a region and

a lot of that depends on
how hard you're being hit.

I mean Florida is getting
clobbered by sea level rise and

by hurricanes I mean Florida
is mobilized on this issue.

Georgia has not been hit
anywhere near as hard.

Other than the drought I think they're
starting to a paid attention largely

because of the drought.

So it's a challenge.

Here's what we can do right now in
Atlanta we need to assess our water

resources future needs.

And the engineering and policies
required for a sustainable water supply.

We need to improve Atlanta's storm
water management sewer system.

We need to aggressively protect our trees
enhanced our public transportation system

implement energy conservation and
efficiency strategies.

And for the reduction in carbon emissions
or require clean energy technologies.

So all of these make sense
even if the most dire

predictions of the climate
models aren't wrong.

And it's really going to be much milder
all of these things make sense in

terms of making our city less vulnerable
to random weather variations and

also in terms of our economy.

But we live in the challenges for
the world.

I mean we live in a global community.

And you know what we're looking at
the potential for possibly a doubling

of the people on the planet in the next
century which is going to increase

the burden on the earth the earth's
resources and increase need for energy.

And the combined challenges of

population increase resource consumption
environmental degradation and

climate change are our real
challenge to global sustainability.

Now what can we do about this.

Well.

There's one of the big challenges
is trying to OK there's data and

there's models and scientists are doing
stuff but there's a lack of a lot of this.

It's not really turned into information
that people can actually use.

OK How how does a water research
source manager actually use this.

So no and other

agencies are actively putting together
plans for a National Climate Service.

Which links what scientists
do with the decision

making process and
much better information and

Decision Resources and really
identification of key knowledge gaps.

So we can address in a better
way with really useful

information data that people
making decisions about ecosystems

water resources forests agriculture
energy human health air quality fisheries

transportation in the coastal zone
actually have some useful information.

Georgia Tech is is involved in this
area and I literally submitted yet.

Day A propos No Tuesday proposal to
no offer a cooperate of Institute for

Climate services.

And this is in partnership with
a number of other universities

in the region that includes.

A variety of elements everything
from satellite climate data records.

Climate model testbed
satellite data simulation and

realises information technology and
decision support tools social science and

sector applications climate services and
stakeholder interactions these key

issues of fresh water resources Marine and
coastal systems atmospheric composition

and air quality land surface resources and
climate in extreme weather events.

The idea is to really
develop the intellectual tool

the intellectual foundations and
the practical tools for

a Real Climate Service to help
people make better decisions.

And also on the university level there's.

The American college and university
presidents climate change commitment and

more than six hundred US college and

university presidents have committed
to achieve climate neutrality through

reduction of greenhouse gas emissions and
carbon offsets.

And Georgia Tech was an early leader in
this whole green campus movement with

lead silver buildings and.

Tech trolley and our landscaping
in a whole variety of things and

Princeton Review has.

Great Georgia Tech in the top ten
nationwide in terms of green campus.

And people say well you know reducing
greenhouse gas of this campus I mean

that's like less than one percent in
terms of the greenhouse gas emissions but

the real impact is all of
the corporate and political leaders of

the future are in our universities now and
they pass through our universities and.

It's having them work being educated about
this issue and work on the technologies to

enable this carbon neutrality is what's
going to make a difference in the future.

So this is.

You're all going to be this is a problem
that your generation is going to is going

to be facing and your generation is gonna
you know find the solution one way or

another and so
I urge you to participate in the growing

movement in Georgia Tech largely through
you know the green and the Institute for

sustainable system there's all sorts of
student organizations that are popping up

to help understand this issue and
come up with practical solutions and

there's a whole host of new
courses being developed

that you can get engaged
to learn more about this.

OK Thank you.

Thank you very much for your long time.

Well you know that

you realize you know you work.

Locally so why

drag this drought doesn't have
anything to do with global warming.

It's a it's a graphic illustration
of the impact that a drought

can have on our economy and
our ecosystems the drought as

you know natural variability
there's no particular attribution.

Of the drought in Georgia to
global warming that I can tell but

it's an illustration of the impacts.

It's yours.

I mean you're in a good explanation why so
roughly a hundred years from this.

This dust settles yours rise.

Well they started to rise.

Now though they've been rising but
in terms of getting a cumulative impact.

Individual YOU HAD TO takes a while to
accumulate enough in the atmosphere.

OK so it was been ramping up and in terms
of the economic development in the one

nine hundred fifty S. I mean the fossil I
have these graphs I didn't bring them but

in terms of you know the one nine
hundred fifty S. that really says.

Started accelerating exploding in terms
of you know the amount of the rate of

increase of carbon dioxide into the
atmosphere and the the energy generation.

So it accumulates and

the rate of emission really kicked
then around one nine hundred fifty

zero zero zero zero

zero zero one

one zero zero zero zero.

Sure.

OK All right.

And what were your argument about three
hundred degrees Kelvin I mean that

the range of temperature on the earth is
much lower than three hundred degrees

Kelvin OK but
the range the observed variation was

well there's nothing on the earth and

there's no physics that's
going to send the earth.

And.

To absolute zero or something like that.

I mean there's given our
distance from the sun.

OK we operate and we have certain
constraints on what the temperature can

be and it's not a range of three hundred
degrees Kelvin unless the sun goes out.

OK so based on that there are tens
of millions of degrees of

freedom in the climate models in terms of
each little grid point each variable and

whatever tens of millions
of degrees of freedom.

In terms of what you would
call tunable parameters

there's arguably one hundred or
so order of one hundred.

And these are these
parameters are constrained.

You know within certain observations and
certain physics and whatever but

they are tuned.

Now you can in principle
tune to get one result but

you can't tune to get
a whole time series and

I told spatial distribution both an X.
Y. and Z. over the whole globe.

OK so you can tune and
you can maybe tune to an average or

a number but you can't get a credible.

You can't tune to get a credible
time steer ease of the space.

The spatial distribution of things.

So if you can't tune these models to

get whatever result you want
in any sort of credible way.

So again it's one of the most
complex models anywhere.

These global climate
models with an extremely

large number of the degrees of
freedom order of one hundred.

Tuning knobs.

Now if you want this discussion.

You know what time runs

more than willing this war

is over.

What was yeah.

Yeah.

Exactly.

OK now there isn't that much fitting and
as the climate models mature they get rid

of more and more of these tuning knobs and
I'll give an example of fan

I mean one of the biggest on certainties
is dealing with aerosols and clouds.

OK the research that the analysts
as been doing has removed.

A dozen of these tuning knobs because
we've now got the physics treated in

exactly the right way that makes sense
on the scale of the climate model so

as research proceeds.

OK We have valuate these processes and
whatever and that's an example of how

you know the climate models in one nine
hundred ninety had a whole lot where a lot

cruder and had a lot more of these broader
base tuning knob I mean that the tuning

knobs are really very subtle you know in
terms of the sea ice it's about what is.

What is the size distribution
of melt ponds on the sea ice.

OK And in terms of an overall fraction and

what are their very subtle
things are not gross.

They're not gross things that
are going to really change

the model in an enormous way.

So the models are getting quite mature
they're nowhere near perfect but

they're getting quite mature.

There's there is thousands of people
tackling aspects of this problem.

You know on the mitigation
adaptation front.

I'm not quite.

OK.

What what I'm what upsets me more
than anything is the fact that

we didn't start working on all
the adaptation strategies a decade ago.

OK And look at where we
would have been working out

how to make ourselves less vulnerable to
all these hurricanes and natural disasters

before they even struck that may or may
not have anything to do a global warming.

If we had a sensible water
management plan in Georgia.

We wouldn't have seen this disaster
that we had in two thousand and

seven in terms of the drought and
running out of water.

You know that to me this is
the biggest thing and the.

The technologies.

For green energy.

I would have supported more
technology development for

the last decade in terms of what
policy what I do in terms of

capping C O two at a given a mission or
what technology is going to work.

You know I'm just not
an expert on all that.

Yeah.

Absolutely.

We're still going to get clobbered by
droughts and hurricanes and whatever let's

go ahead and you know fix these thing
Atlanta needs a mass transit system.

You know just to make the place livable
forget about the greenhouse gas emissions

you know you've got air quality you've got
all sorts of other reasons besides global

warning telling you need a mass transit
system in Atlanta things like that.

Let's do the things that make sense.

You know.

Anyways.

Because you know.

Things we can do first half of
the series is still talks about

Gene Klein things like that a second.

Alternative or so
as we go through the series.

We'll have opportunities to talk about
some of the things we do all our life time

you're still going to dominate our

beautiful easy.

They're always going.

You know.

Pretty much everybody was a lot.

It was posted.

OK they had formal reviewers.

OK it was posted and
any number of people reviewed.

You know a lot of people reviewed it you
had to know where to look and whatever but

it was sort of an open and
all sorts of people reviewed it not.

Scientists you know from industry bloggers

everything there was all
sorts of stuff in the.

Net and there were certain complaints
about the way some of the.

Reply The rebuke questions were handled.

You know I've seen some of
those in the blogosphere but

overall it was a pretty
comprehensive review process and

before anything goes out they
actually meet with policy makers

advocacy groups government
oil companies Saudi Arabia

the whole worker in the room and they
argue about how everything is worded and

some you know some Saudi Arabia I don't
like that one and they say and then they

argue about it and maybe we can reword it
or say no this is what the scientific.

I mean this goes on for weeks.

You know how things should be worded
having everybody air their concerns.

You know they have.

All over the place and there was a very
large group of skeptics from the US that

attended the scientists policy duke out
before the Summary for Policymakers was.

Presented.

You know getting every question answered
resulted in some few rewordings I was

getting calls from Paris about a lot of
people were going after the hurricane

warning and how this was being
wording there a lot of pressure

from the US to tone it down because of
the sensitivity owing to Katrina and

I was getting Thinking back and forth.

You know all of this stuff was.

But the scientists stood their
ground they changed the wording and

some things to clarify so there was no
confusing but the amount of scrutiny

peer review and employ it from all sectors

all perspectives sort of unprecedented
in any kind of scientific activity.

Is it perfect.

No but each time it gets better.

And it's like an unparalleled activity.

You know anywhere in the Thiele to
anything it's fairly incredible.

It's

very tough and I've taken a personal
interest in that not all relate to you.

I mean that the biggest challenge
is in the even Jellicoe community.

You know when people think the earth
is six thousand years old.

They don't believe the paleoclimate they
believe that they don't particularly

like the scientific men.

The the word theory is an eighth of
a to them they think that's a game

you know that is very anti scientific and
I've joined a group of

scientists and even the intelligentsia
of the even Jellicoe movement in fact

we have a meeting at Merced said college
sometime in February where we're trying to

figure out how we can work decide on
what we agree on what and what we do.

Let's throw out the evolution stuff and
not worry about that but let's talk about

creation care which is something that
they're interested in and try to frame it

in ways that they can understand and
values that they have a lot of it is.

You have to work with them and you have to
understand where they're coming from and

you have to figure out
ways to convince them.

In ways that they can understand and
appreciate that's consonant with their

value system and if you're ever going to
change people's individual behaviors.

Who better to do it than the preachers.

OK who meet with a large population about
how you can conserve and recycle and

whatever so there's a lot of it's very
difficult is very frustrating but if you

go to war and try to raise it
by being extremists and scary.

Whatever it doesn't play
well you just have to

understand where they're coming from and
work with them.

It's hard and

Georgia the politicos in Georgia
have been a very tough nut to crack.

I'm not a big fan of carbon
offsets because I think.

You know it's a feel good thing
to buy these carbon off so

there's no way to monitor it and you know.

Terms of forests and

there's no way to assess whether it's any
good at the end of the day the people

who are using the energy aren't reducing
their consumption or fossil fuels or

just paying the money hoping somebody
else is going to do it you know what if

everybody has that same attitude and it's
very difficult to monitor So this whole.

Cap and
trade with big reliance on carbon offsets.

I'm not a huge fan of myself
very difficult to monitor.

Really.

Very well

as we basically All right.

One wall right.

Exactly the way to look at it
you know it's an issue of risk.

You know and cost loss and
consequences and

whatever and
this Asian making on under uncertainty

is done in every field all over the place
in everything from foreign policy.

You know invading Iraq because we
think they might have you know weapons

of mass destruction that was a pretty big
un certainty and that the solution we

make decisions all the time for better or
for worse under a great deal of

uncertainty and the challenge is to
acknowledge that there's uncertainty but

figure out what the potential risks
are and what the cost loss is of doing

the various you know potential options
that's exactly what you need to do right.

Yes or no and then you

think that was OK You know we're

really good.

There was a National Academy of Science
report in one thousand nine hundred

seventy nine bed assess the state of
climate modeling at that time and

said that the state of
our capabilities and

climate modeling was inadequate
to make any future projections.

OK That was a National Academy
of Science assessment in one

nine hundred seventy nine.

Climate models made a rapid development.

OK in the eighty's and
now there is increased

support political pressure whatever to
keep improving the climate models so so

the climate models have developed
explosively in terms of complexity

of parameterization resolution
running multiple members of

a large ensemble etc So so
the climate models of today.

Are nothing like the climate models of
one thousand nine hundred ninety and

certainly nothing like the climate
models in one nine hundred seventy.

So it's just a way to all the science

understanding of how to run
them how to build them etc and

that is just increased explosively
over the last few decades that you're

one

of the.

Right.

Well I mean.

Yeah.

Canada Russia.

I mean you know.

So you know.

OK Well it's an issue in many ways
just a from the U.S. point of view.

Why should they care of Bangladesh gets
flooded out or something like that.

Well the issue is that if you take a state
a country with a population the size

of the U.S. cram it into a state the size
of Wisconsin they're going to lose a third

of their land due to sea level rise
not to mention disastrous hurricanes.

You know you're going to
see mass migration out of

that region which is going to result
I mean where where do you put them.

All the religious turmoil the got the got
to go somewhere going to be massive

destabilization political destabilization
in that region which then impacts the U.S.

OK geopolitically So you know we're all
once you start thinking about it that way.

And so well Minnesota is going to be fine.

OK but if Minnesota relies on.

The rest of the country to
produce goods or by it's goods or

whatever you start to see
how connected things are so

in the short term it's very
easy to think about locally but

I think people are becoming more educated

as to how we're all connected and
with this global financial crisis.

You see how something happening one place
can have these trickle affects globally so

we're realizing how vulnerable we.

Are and how connected we
are I think what's happening

with your treatment of
genes in terms of risk.

Well pleased for you

I I engage with the insurance
companies quite a bit.

The insurance companies
have a five year horizon.

They're just now starting to think out
what could be happening on the ten to

twenty year horizon.

I mean they think you know
the odds of one of those

companies being out of business
in twenty years is pretty high.

I mean they just don't think on
the hundred year time scale.

Building decisions and

sure you know it's made on the twenty
year at most kind of time scale so

they're interested in the five to ten
to twenty year kind of time scale and

that's one that scientists haven't really
been focused on because then you have

these big cable modes of variability
on top of the global warming and so

I think this is where the.

A lot of interest is being
generated on this the cable

kind of stuff what's twenty
twenty going to be OK so

the insurance companies you know
companies are very interested but

we don't but but their time scale five
to ten to twenty years isn't one that

we can give them a lot
of help with right now.

Right here

or

no way.

OK clouds globally have
a cooling effect but

it depends on the height of the cloud if
there are high clouds they have a warming

effect clouds in the polar
regions have a warming effect.

So the effects of clouds are very complex
and again this isn't an expertise of

fantasy the cloud effects are very
complex but we're not seeing and

in terms of the cloud feedbacks and cloud
forcing the models do different things.

OK So you know it is one of the bigger
uncertainties but there's not there's not

going to be any miraculous cloud thing
that's going to happen that's going to

cool everything down in terms of where to
go to get information on climate modeling

there's a few blogs out there that do
a good job of trying to describe things.

Real Climate dot org.

I'm not a big fan of it but
it does have some good descriptions and

tutorial type things about
climate models there's

I think Tamino I can't remember
what his blog is called.

But there's a number of blogs out there
that would appeal to a person trained in

physics that explain a lot of this so so
there are some good blogs and if you send

me an e-mail I could recommend some blogs
to try to go to and some sources for it.

So you can use.

Them.

You know I don't know and

that's the one thing you know this whole
issue of abrupt climate change in this

whole tipping point issue I mean this is
like a real hot button issue and it's one

that we don't really know we don't kick
off even in the simulations out to

twenty three hundred we don't kick off any
of these things although we don't have to.

Amichai sheets in the model yet.

For example.

So we really don't know how this ice sheet
one would play out because we just now

people are starting to get interactive
continental ice sheets with the climate.

You know also so that's something
hopefully with the next round of I.P.C.C.

runs we will see that but
to me that's the big one.

I think sea ice if we melt
back the completely melt

the sea ice in the arctic during
the summer time I still think that

that can recover relatively easy I don't
regard that one as a tipping point and

I do have expertise on the Arctic sea ice
but the big one is these continental ice

sheets and we just don't have them
interacting with the climate models yet

but that should be coming
in within a few years.

You might

hear very nice.

Thank you.

Concert

relationship with global warming for

example presentation

States senators

basically compilation

you know

when you look you know I've learned.

I've looked at all of them and

I've even engaged in the blogosphere on
Climate Audit periodical way to you know

engage in count of the people
who actively publish and do.

I mean he's really come up with some
new things that have forced people to

you know some of the climate
scientists were sloppy somewhere and

he pointed out they have to go back and
do their homework so so this whole but

there's a lot of craziness out there too.

That is just noise and
the unintended impact of what Inhofe and

those guys have done has
distracted from the adaptation

stuff that we could have been doing for
the last ten years to you know and

as a result we haven't had a national
assessment we don't really know how to do

all these adaptation things and people are
getting and creasing really panicked and

talking about drastic
mitigation activities.

But I think people are now talking about
more drastic mitigation things which was

exactly what he was trying to forestall.

He's more worried about the mitigation
of the oil company rather than random

adaptation activities that was
the point I was trying to make.

You know very.

Well we owe you.

What's.

No I mean

the world and cars and I think

that's a lie but

I got there and that's

what I

get out very nicely put.

You know.

Huge I mean I mean number one
sort of different line defend.

Against global warming.

I mean in terms of keeping the ground
cool taking up carbon dioxide

regulating you know water
protecting from drought.

I mean this is yeah it's a huge issue and
a lot of people study it and

I collaborate with some people at Duke
who do a lot of this kind of research.

Well this is what the carbon offset
sort of stuff does is it grows trees.

OK.

You can't solve the whole problem
just by growing trees and

that's sort of what the car from
upset is mostly trying to do.

It's an important thing to do but I don't
think it's going obscenities thing by

a critical thing is to stop the cutting
down of forests in Indonesia and

Central and South America.

I mean that is if we can
help their economies or

whatever give them
something else to do so.

I don't have to cut down the trees.

You know that you know

this is came to mind a comment
from over there about

the inertia in us and
in Europe especially in Georgia.

I see.
So

if I want to most of us you know
graduation speeches of all time by

Jared Diamond and collapse and

he was talking about not
only population increase but

when we look at people who are in the
third world or you know I'm self-taught

you versatile as that is I mean or
improving their economic wellbeing.

It's the equivalent of ten billion sixty
some odd billion people in consumption.

But what what you brought up was one
of inertia here but you're still

the other five billion people that are not
it's not inertia it's acceleration.

You know I billion people
you know that are in

the rest of the world who do not currently
have the balls if you will not look in and

think about looking directly at.

For a technological I mean if we could
if we could do one thing it would

be to deal with the coal problem in
China either get them some other

fuel that they can use or do you know
clean coal or carbon sequestration or

whatever that in itself would
soften the picture and I think

someone who works in solar energy we think
a lot about energy production in the U.S.

or in Europe the fall recently when
they live for the entire group.

So these technologies which might not
be ready for prime time to the U.S.

Now maybe there are more efficient things
that are inexpensive can be brought.

Yeah I mean that they could do the early
adopters because they could definitely be

the early adopters as well because
we don't have to you know one

more question.

What is the total situation.

Yes And
in terms of units OK parts per million.

I can you do water vapor in parts per
million three hundred at this grand for

kilogram is what I usually
think of it like it.

Yeah it's a thousand times
more water than carbon dioxide

is more than you do and
that's why it was so much.

Yeah yeah.

So then last question.

Gene.
So

as you can resolve.

So will

be why.

One hundred

years and so on so

my hope to

come with you and ten thousand years.

This will all be there will be
a non-problem OK everything all of them

going out a little bit of
your now I don't think so.

I don't think we're there we're at
anywhere near the peak oil is my

guess right.

So yeah you can be bought into

your yeah when one that your gas is great.

I mean nobody's complaining about
natural gas coal is the big bad guy.

So if you can I mean fossil all fossil
fuels are not equal in their guilt here.

I mean coal is the bad one.

Natural gas is relatively good
goals are you OK with that.

And let's let's wrap up of.