Basics of numerical coupled modelling

1
Climate Change, Science, The Public and the
role of Education Antonio Navarra INGV George
Philander Princeton University
2
Raffello, la Scuola di Atene
De Meteorologica However, all the mouths of the
Nile, with the single exception of that at
Canopus, are obviously artificial and not
natural. And Egypt was nothing more than what is
called Thebes, as Homer, too, shows, modern
though he is in relation to such changes.
() This happened to the land of Argos and
Mycenae in Greece. In the time of the Trojan wars
the Argive land was marshy and could only support
a small population, whereas the land of Mycenae
was in good condition. But now the opposite is
the case, for the reason we have mentioned the
land of Mycenae has become completely dry and
barren, while the Argive land that was formerly
barren owing to the water has now become
fruitful. Now the same process that has taken
place in this small district must be supposed to
be going on over whole countries and on a large
scale. () So it is clear, since there will be
no end to time and the world is eternal, that
neither the Tanais nor the Nile has always been
flowing, but that the region whence they flow was
once dry for their effect may be fulfilled, but
time cannot. And this will be equally true of all
other rivers. But if rivers come into existence
and perish and the same parts of the earth were
not always moist, the sea must needs change
correspondingly. And if the sea is always
advancing in one place and receding in another it
is clear that the same parts of the whole earth
are not always either sea or land, but that all
this changes in course of time.
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should gardeners be scientific, should cooks?
Botany helps gardeners, laws of dietetics may
help cooks, but excessive reliance on these
sciences will lead them and their clients to
their doom. Isaiah Berlin (1909 1997)
The division between the two cultures is wider
than ever, since the original C.P. Snow remark in
the 50s. The interactions between the two
cultures are more complex than ever
4
At the core of the climate problem is the
relation between science and social affairs
(politics)
Most issues we are dealing today contain elements
of both, lets exemplify with an allegory
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The boat (I)

• The situation of climate change today is similar
  to a situation in which a grooup of people is
  sailing on a river in a small boat and someone
  come up with the notion that there is a fall down
  the river, unseen. A lively debate follows trying
  to establish two things
• How far is the fall ?
• When to get off the boat and land on one of the
  two banks ?

6
The boat (II)
The first question is a scientific question,
there is only one answer and debate will not help
in getting it faster. The second question
is a political question, there is no unique
answer, also because the banks are unknown,
possibly unsafe, since cannibals can live there.
7
Albert Einstein, to a report in the New York
Times of May 4, 1935 on a scientific dispute
involving his work It is my invariable
practice to discuss scientific matters only in
the appropriate forum and I deprecate advance
publication of my announcement in regard to such
matters in the secular press. We cannot indeed
decide by a vote the orbit of Mars
The boat (III)
The second question can instead benefit from a
public debate. People will react using the set of
values that they possess, compromise are possible
and desirable.
8
We have known the sin
Nuclear scientists have known the sin a long
time ago, their sin being the power and the
corruption of a priviliged relation with
politics. More recently, climate scientists have
come to know the same sin.
9
Realistic Example
During the winter of 97-98 scientists advised the
people of Zimbabwe in Africa that rainfall there
would probably be below normal, unfortunately
Zimbabweans had normal rainfall and were
unprepared. Because of the expectation that
crops would be poor, and that farmers would be
unable to pay back any loans, banks in Zimbabwe
declined loans to farmers. The consequences were
dire crop production was 20 below normal. The
prediction of a drought in effect caused a
drought.
10
Did they fail to appreciate the significance of a
probabilistic forecast? What motivated
scientists to make forecasts for Zimbabwe in
1997? Concern for the people of Zimbabwe was of
course a major factor, but to what extent were
the scientists responding to pressure from their
sponsors to demonstrate that their results can be
useful?
11
During the Cold War scientists studying El Niño
enjoyed remarkable freedom to do science mainly
for the sake of understanding an intriguing
natural phenomenon, but since the 1980s the
sponsors of scientific research have insisted
that the focus be on research with practical
benefits. For science to flourish, scientists
must have a skeptical attitude towards their own
results, constantly questioning and testing
apparent solutions to problems. They have to
adopt a very different attitude when trying to
persuade potential clients that their results are
useful. How are scientists coping with this
predicament? To what degree are such difficulties
contributing to the poor communications between
scientists and nonscientists?
12
The Priests of the Oracle
Predictions are the distinctive sign of science,
therefore it is shocking when scientific
predictions come associated to a high value of
uncertainty In our previous boat example the
scientists in the ship give different estimate of
the distance of the fall. Is this disagreement
reflecting a real scientific problem, like
different estimation of accuracy, for instance,
or it is rather expressing the pessimistic and
optimistic character of the the
scientists. These problems come up because they
live in two worlds, they are scientist, but they
are also citizens. They are people, not the high
priests of the Oracle.
13
Uncertainties
Uncertainties complicates the issue enormously.
Consider now the previous example of the fall,
but imagine that now the problem is that it is
not a fall, but a sequence of rapids of
increasing strength, and that we do not have only
one boat but a small fleet of very different
types, small and big boats, rafts, gondolas.
Determining the distance is now much more
difficult, the distance to which rapids and of
which intensity ? Deciding when to leave the
river is also very controvesial. Some passenger
of the boats denies the existence of the rapids,
the owners of the small and fragile rafts and
gondolas aer seriously worried, but the partying
passengers on the big boats consider the big
rapids that terrorize the raft poeple a pretty
jolly show. Reaching a consensus on leaving the
river is hard, harsh negotiations follow and last
probably till the rapids.
14
Education
So we cannot leave the political decision to
scientists and we cannot ask for a scientific
conclusion from the public But we can do
something. Public health has made huge gains in
the last century because of the great
improvements in drug and medical technology, but
also because each of us is much more aware of the
fucntioning of our body. Most of us know what is
good and what is bad for our body and we act
rationally on it. We need a wide education of
the functioning of our planet, each of us need to
be much more aware of the basic workings of the
our planet.
15
Any time left ?
Mankind is a geological agent and we are
modifying quickly, how much time we may have
? Exponential process are very tricky.. Imagine
a pond where there is a lily one day, and two the
following day, and then four, eight At which day
we should decide to do something ?
Day 1
Day 2
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Lanidride carbonica
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Climate Change is a very serious problem
It is far too serious to be left to specialists,
And the organized skepticism of the scientists
may not be the best method it is necessary to
have a very wide understanding of the working of
the working of ther system to reavch a solution
trough the methods of social affair
18
Optimists

• But concerned

19
Lorenzo Stecchetti
Olindo Guerrini
Argia Sbolenfi
Maudit Printemps reviendras-toujours ?
Primavera che tu sia maledetta! Che fra i rami
de tigli io la vedea Allor che sola al suo
balcon sedea Linverno a far lamore e la
calzetta. Baciandoci con gli occhi, alla
vedetta sempre stavamo il di, ne fronda
rea Linnocente baciar ci contendea Gia il
difetto del tempo e la gran fretta! E il mal
tornato sole ora discioglie Lamica neve e i
tigli alla leggiera Aura del novo april metton le
foglie Un fitto vel di fronde, una severa Siepe
di rami i baci suoi mi toglie Che tu sia
maledetta primavera!
20
Zibaldone, 1827 Egli e pur certo che lantico
ordine delle stagioni par che vada pervertendosi.
Qui in Italia e querela comune che i mezzi tempi
non vi son piu, e in questo smarrimento di
confini, non vi e dubbio che il freddo acquista
terreno. Io ho udito dire a mio padre che in sua
gioventu a Roma, la mattina della Pasqua di
resurrezione si rivestiva da estate.(Magalotti ,
1683). () Quello che tuti noi sappiamo,e che io
mi ricordo bene, e che ne la mia fanciullezza il
mezzogiorno dItalia non aveva anno senza grosse
nevi,e che ora non ha quasi anno senza nevi che
durino piu di poche ore