Going to Work in Antarctica:
Doing Science at the Bottom of the World
Susan Solomon

Senior Scientist, NOAA Aeronomy Laboratory

1) A Travelogue (because itwas fun)2) What I did there: The
National Ozone Expedition
1986/73) Some of my other work(and all of it was fun)4) What other scientists doin Antarctica (because it is
one of the greatest
laboratories on Earth)Arctic

Antarctic

There is a hole in our ozone layer over Antarctica every spring:
It was a
shock tothe world
when itwasdiscovered,and itchangedmy life.

Three kinds of ozone: good (stratosphere), bad (troposphere), andugly (smog).

Plant grown in normal light

Plant grown in extra UV lightTheNationalOzone
Expedition:
4 researchgroups, 16
scientists,5000 kg
equipment

On the tarmac in New Zealand
3:00 am August 23, 1986

A special polar airplane on skis

One aborted flight and nine hours later.

McMurdo Station, Antarctica: the Tokyo of Antarctica

Everything is recycled, very carefully.

There are some cool places nearby

All of Antarctica is a magnificent crystal palace

Reactions among gases only:

Risk of long-lasting
effects…..
But only a theory….
A small effect….
Far in the future…

100

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Launching ozone-measuring balloons

Missing total ozone, but from
WHERE in altitude? Only theSyowa data could tell us.
35

Syowa Station
Ozone Balloon Data

20
15
10

1965-1976
1980-1986

Amount of Ozone

2.00e-4

1.50e-40

1.00e-455.00e-5

The ozone was missing
from the heart of the layer,
10-25 km, not 40 km aspredicted from gas-phasechemistry. I am very
grateful to Japanesescientists for this data.

250.00e+0Approximate Altitude (km)30

A new and different kind of ozone depletion.
Why only in Antarctica? Why in the spring?
Why at those altitudes, where it shouldn’t be?
Clouds.

40

Gases destroy ozone here

Altitude (km)Polar cloud surfaces lead to much
more ozone destruction, in theheart of the layer

HCl20 20ClCl2

ClONO2C l O Ozone
0
Amount of ozone

Activated
Reservoirs
for ozone loss

Chlorine teams up
with two key factors:
sunlight (spring) andicy cold surfaces(Antarctica)20

Why is there an ozone hole over Antarctica? Only measurements could
prove it.

We could measure chlorine dioxide:

-70

Oct 1

Sep 1

10Oct 1-60

Sep 1

Observations At McMurdo Station (77.8°S)

1Chlorine Dioxide
Chlorine Dioxide
Detection Limit-80-90240.1Temperature
at 18 km
250260270

Day of Year280.01290240250260270

280

Day of Year

100x more OClO than there should havebeen: A fingerprint in seasonal behavior

290

Expected For
Gas-Phase
PhotochemistryDe Zafra et al. And
Anderson et al. measured
ClO in Antarctica.
Solomon et al. measured
OClO, a closely related
molecule.

Now we have satellites for the bird’s eye view….
Antarctica: coldnearly every year,with some variability
Ups and downs in
Antarctic ozone
depletion reflect cold
and warm springs in the
Antarctic stratosphere(not a recovery or aworsening).
A very unusual warm
Antarctic stratosphericspring occurred in 2002.
But the ozone hole will
be with us for decades.

Arctic:
More variable but there
is substantial ClO(and OClO) andsome ozone
depletion (up toabout 25% in coldyears)
Warms up earlier andClO disappears
sooner….note howmuch less ClO ispresent in March in
the Arctic than the
Antarctic in
September.

0October

2Year

2004

31994

1984

1974

1964

Ozone Abundance at heart of PSC layer

4
Syowa

Ozone
very
nearzero

1

30

25

25

20

15

15

10

1965-1976
1980-1990
1994-2003

55-20

0

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Ozone Partial Pressure (hPa)2.0e-41.5e-41.0e-4% Depletion
5.0e-500.0e+0Approximate Altitude (km)Observations
1980-1990
1994-2003
ModelsSolomon et al. (1986)
Portmann et al. (1996), updated

Syowa Station
Ozone Data

35

The rightfingerprint inaltitude

There’s a hole in Antarctica’sozone layer. It’s due to thechlorine put into theatmosphere by people. The
chlorine is more effective atdestroying ozone where it’scold, due to reactions on polar
stratospheric clouds inside thestratospheric vortex.

Antarctica is the coldest place on Earth, so it has more polar
stratospheric clouds than the Arctic, and more ozone depletion.

Most scientists who work at McMurdo live in rooms like thisSome scientists live in field camps, studying the flow of ice….

Or digging up ice cores; bubbles in the ice show what the atmosphere
was like up to about half a million years ago.

Some information about carbon dioxide changes through four past iceages (from ice cores), and in the modern era (from global data)
The past 100 years
350

Carbon Dioxide Amount (ppmv)

Last interglacial
Last Ice Age
300

250

200

400x103300

200

Years Before Present

1000

It is well established that there is more carbon dioxide in theatmosphere today than there was in the past half million years humans are ‘forcing’ the system in a new way.

Ice agesarecausedbyearth’s
orbitalclockAntarctic weather instruments are part of the global climate network

55.4

Year
2000

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14.5

57.4
14.0

56.4
13.5

13.0

Annual Mean Temperature (°C)

58.4

1900

1880

Annual Mean Temperature (°F)

15.0

GlobalThis is Antarctica’s only year-round resident

Rocks are of interest too

Some Antarctic rocks have living things under the surface - a form ofalgae. Could life on Mars be like this?

Some brave scientists dive under the sea

To study creatures like this shrimp-like animal

Ozone depletion from pole to pole, and in between:

When will the ozone layer recover?
A typical CFC:I received the National Medal of Science in 2000 for my work
explaining the ozone hole. It was a wonderful honor. The Blue
Planet Prize is an international honor that also humbles me.

And a great privilege was going to Antarctica and doing the work,
together with wonderful colleagues.

Do I look happy?