The film shows a disastrous and
abrupt climate change. Due to man-made global warming, first the
Larsen B ice shelf breaks up (this did happen in the real world,
of satellite images - allegedly only after the authors had written
it into the film). This event is used to introduce the main paleo-climatologist
character, Jack Hall, who is drilling out there and narrowly escapes.
Later, in the north, meltwater inflow brings the
North Atlantic Current to a halt, causing severe cooling. This happens
in a matter of days. A super-storm is triggered by the oceanic shutdown.
This covers much of the northern hemisphere in a few giant cyclones.
It causes the flooding of Manhattan, huge hailstones in Tokyo, tornados
in LA, and several days of severe snow storm covering the entire
northern continents. In the eye of these super-cyclones extremely
cold air is sucked down from the upper troposphere to the surface
and shock-freezes the Manhattan sky-scrapers. When the super-storm
clears after some days, most of the northern hemisphere is snow-covered
and doomed to a new ice age due to the well-known snow-albedo feedback
(i.e., the snow reflects so much sunlight that the climate stays
Obviously it is easy to dismiss much of this scenario
as unrealistic and exaggerated. It is – and viewers will be
in no doubt that they are watching a fictional disaster movie and
not a documentary. As an example: the flooding of Manhattan is described
as a wind-driven surge, although this kind of massive wave (called
a tsunami) could only be caused by an undersea earthquake
or landslide or a meteorite hit - not by a storm or a change in
the North Atlantic Current. And the shock-frosting in the eye of
the storm defies the laws of thermodynamics.
The film makers are quite
up-front about the fact that it's not a scientifically realistic
scenario. The publicity material provided by the film company Fox
says that when scientists talk about abrupt climate change they
mean five or ten years, but that for dramatic reasons everything
was compressed to a couple of weeks. In an interview, director Roland
Emmerich also says that he is well aware that things could not happen
in such a short space of time and that he knows the difference between
weather and climate, but that they had to construct their own private
theory to squeeze the theme into a 2-hour blockbuster movie format.
To portray the dramatic effects of a major climatic disaster within
a short time span, they simply took known weather extremes –
tornados, storm surges, cyclones, hail storms and blizzards –
and amplified those.
On the other hand, given the rules and constraints
of the genre, it is remarkable to what extent the film-makers have
tried to include some realistic background. Early in the film a
UN climate conference in Delhi is shown where Jack Hall gives a
talk about the possible risk of a shut-down of the North Atlantic
Current. I gave a very similar talk at such a UN conference in Buenos
Aires in 1998 - I even showed the same diagram. In the film talk,
Hall states that a shutdown might occur in a hundred years, or a
thousand, or not at all. Many real climatologists have said the
same thing. In this way, what climatologists think is presented
in a realistic way in the film, and it is very clear that the rapid
drama that later unfolds is counter to what any climatologist expected
- it's where the fiction starts.
The politics of climate change is also presented
well. It is chillingly realistic how the head of the US delegation
(the vice president in the film) responds to Hall's presentation.
Thus small scenes with few sentences of dialogue are cleverly used
to introduce a number of key ideas and conflicts, which are very
familiar to climatologists but not to most of the people who will
go and see such a movie. I also find the film quite successful in
giving a flavour of the world of climate science – I did recognise
our world, what the work places look like, the pictures on the wall,
how the climatologists talk, etc.
After a preview of the film in Berlin I had the
chance of a good talk with the script writer, Jeffrey Nachmanoff,
and I was quite impressed how well-informed about the science and
politics of global climate change he was.
Clearly this is a disaster movie and not a scientific
documentary, the film makers have taken a lot of artistic license.
But the film presents an opportunity to explain that some of the
basic background is right: humans are indeed increasingly changing
the climate and this is quite a dangerous experiment, including
some risk of abrupt and unforeseen changes. After all - our knowledge
of the climate system is still rather limited, and we will probably
see some surprises as our experiment with the atmosphere unfolds.
Luckily it is extremely unlikely that we will see major ocean circulation
changes in the next couple of decades (I’d be just as surprised
as Jack Hall if they did occur); at least most scientists think
this will only become a more serious risk towards the end of the
century. And the consequences would certainly not be as dramatic
as the “super-storm” depicted in the movie. Nevertheless,
a major change in ocean circulation is a risk with serious and partly
unpredictable consequences, which we should avoid. And even without
events like ocean circulation changes, climate change is serious
enough to demand decisive action.
I think it would be a mistake and not do the film
justice if scientists simply dismiss it as nonsense. For what it
is, a blockbuster movie that has to earn back 120 M$ production
cost, it is probably as good as you can get. For this type of movie
for a very broad audience it is actually quite subversive and manages
to slip in many thought-provoking things. I'm sure people will not
confuse the film with reality, they are not stupid - they will know
it is a work of fiction. But I hope that it will stir their interest
for the subject, and that they might take more notice when real
climate change and climate policy will be discussed in future.
For more information on the North Atlantic Current
and the thermohaline circulation (of which it is a part), see the
fact sheet on thermohaline circulation.
A discussion of the risk of a shut-down of this
circulation is found in Shifting
seas in the greenhouse? (Nature, 399, 523-524), and in The thermohaline ocean circulation
- a system with dangerous thresholds? (Climatic Change, 46,
A global warming
scenario that shows such a shut-down was published in Long-term
global warming scenarios computed with an efficient coupled climate
model (Climatic Change, 43, 353-367). You can watch a computer
animation of this scenario.
Finally, the Encyclopedia of Ocean
Sciences has this discussion of Abrupt Climate Change.
is professor of physics of the oceans at the Potsdam Institute
for Climate Impact Research in Germany. For the past 15 years
he has studied the thermohaline ocean circulation and its effects
on climate. In 1999 Rahmstorf was awarded the $ 1 million Centennial
Fellowship Award of the US-based James S. McDonnell foundation.
Since 2000 he has been a member of the Abrupt Climate Change
Panel of the National Oceanic and Atmospheric Administration
(NOAA - the organisation for which Jack Hall works in the film).
He heads the German-Norwegian project
INTEGRATION which studies the possible impacts of future
changes in the North Atlantic Current.