<s>
climateprediction.net	B-Operating_System
(	O
CPDN	B-Operating_System
)	O
is	O
a	O
volunteer	B-Operating_System
computing	I-Operating_System
project	O
to	O
investigate	O
and	O
reduce	O
uncertainties	O
in	O
climate	B-Application
modelling	I-Application
.	O
</s>
<s>
It	O
aims	O
to	O
do	O
this	O
by	O
running	O
hundreds	O
of	O
thousands	O
of	O
different	O
models	O
(	O
a	O
large	O
climate	O
ensemble	O
)	O
using	O
the	O
donated	O
idle	O
time	O
of	O
ordinary	O
personal	B-Device
computers	I-Device
,	O
thereby	O
leading	O
to	O
a	O
better	O
understanding	O
of	O
how	O
models	O
are	O
affected	O
by	O
small	O
changes	O
in	O
the	O
many	O
parameters	B-Application
known	O
to	O
influence	O
the	O
global	O
climate	O
.	O
</s>
<s>
The	O
project	O
relies	O
on	O
the	O
BOINC	B-Operating_System
framework	O
where	O
voluntary	O
participants	O
agree	O
to	O
run	O
some	O
processes	O
of	O
the	O
project	O
at	O
the	O
client-side	B-Operating_System
in	O
their	O
personal	B-Device
computers	I-Device
after	O
receiving	O
tasks	O
from	O
the	O
server-side	B-Application
for	O
treatment	O
.	O
</s>
<s>
CPDN	B-Operating_System
,	O
which	O
is	O
run	O
primarily	O
by	O
Oxford	O
University	O
in	O
England	O
,	O
has	O
harnessed	O
more	O
computing	O
power	O
and	O
generated	O
more	O
data	O
than	O
any	O
other	O
climate	B-Application
modelling	I-Application
project	O
.	O
</s>
<s>
,	O
there	O
are	O
more	O
than	O
12,000	O
active	O
participants	O
from	O
223	O
countries	O
with	O
a	O
total	O
BOINC	B-Operating_System
credit	I-Operating_System
of	O
more	O
than	O
27	O
billion	O
,	O
reporting	O
about	O
55	O
teraflops	O
(	O
55	O
trillion	O
operations	O
per	O
second	O
)	O
of	O
processing	O
power	O
.	O
</s>
<s>
The	O
aim	O
of	O
the	O
climateprediction.net	B-Operating_System
project	O
is	O
to	O
investigate	O
the	O
uncertainties	O
in	O
various	O
parameterizations	O
that	O
have	O
to	O
be	O
made	O
in	O
state-of-the-art	O
climate	B-Application
models	I-Application
.	O
</s>
<s>
The	O
model	O
is	O
run	O
thousands	O
of	O
times	O
with	O
slight	O
perturbations	O
to	O
various	O
physics	O
parameters	B-Application
(	O
a	O
'	O
large	O
ensemble	O
 '	O
)	O
and	O
the	O
project	O
examines	O
how	O
the	O
model	O
output	O
changes	O
.	O
</s>
<s>
These	O
parameters	B-Application
are	O
not	O
known	O
exactly	O
,	O
and	O
the	O
variations	O
are	O
within	O
what	O
is	O
subjectively	O
considered	O
to	O
be	O
a	O
plausible	O
range	O
.	O
</s>
<s>
By	O
using	O
participants	O
 '	O
computers	O
,	O
the	O
project	O
will	O
be	O
able	O
to	O
improve	O
understanding	O
of	O
,	O
and	O
confidence	O
in	O
,	O
climate	B-Application
change	I-Application
predictions	I-Application
more	O
than	O
would	O
ever	O
be	O
possible	O
using	O
the	O
supercomputers	O
currently	O
available	O
to	O
scientists	O
.	O
</s>
<s>
The	O
climateprediction.net	B-Operating_System
experiment	O
is	O
intended	O
to	O
help	O
"	O
improve	O
methods	O
to	O
quantify	O
uncertainties	O
of	O
climate	O
projections	O
and	O
scenarios	O
,	O
including	O
long-term	O
ensemble	O
simulations	O
using	O
complex	O
models	O
"	O
,	O
identified	O
by	O
the	O
Intergovernmental	O
Panel	O
on	O
Climate	O
Change	O
(	O
IPCC	O
)	O
in	O
2001	O
as	O
a	O
high	O
priority	O
.	O
</s>
<s>
Roughly	O
half	O
of	O
the	O
variation	O
depends	O
on	O
the	O
future	O
climate	O
forcing	O
scenario	B-Application
rather	O
than	O
uncertainties	O
in	O
the	O
model	O
.	O
</s>
<s>
climateprediction.net	B-Operating_System
is	O
working	O
on	O
model	O
uncertainties	O
,	O
not	O
the	O
scenarios	O
.	O
</s>
<s>
The	O
different	O
models	O
that	O
climateprediction.net	B-Operating_System
has	O
and	O
will	O
distribute	O
are	O
detailed	O
below	O
in	O
chronological	O
order	O
.	O
</s>
<s>
Therefore	O
,	O
anyone	O
who	O
has	O
joined	O
recently	O
is	O
likely	O
to	O
be	O
running	O
the	O
transient	B-Application
coupled	I-Application
model	I-Application
.	O
</s>
<s>
Classic	O
Slab	O
Model	O
-	O
The	O
original	O
experiment	O
not	O
under	O
BOINC	B-Operating_System
.	O
</s>
<s>
BOINC	B-Operating_System
Slab	O
Model	O
-	O
The	O
same	O
as	O
the	O
classic	O
Slab	O
Model	O
,	O
but	O
released	O
under	O
BOINC	B-Operating_System
.	O
</s>
<s>
The	O
fastest	O
200	O
-	O
500	O
computers	O
were	O
invited	O
to	O
join	O
because	O
it	O
is	O
a	O
200-year	O
model	O
and	O
results	O
were	O
needed	O
by	O
February	O
2006	O
for	O
the	O
transient	B-Application
coupled	I-Application
model	I-Application
launch	O
.	O
</s>
<s>
Transient	B-Application
coupled	I-Application
Model	I-Application
-	O
This	O
comprises	O
an	O
80-year	O
Hindcast	O
and	O
an	O
80-year	O
forecast	O
.	O
</s>
<s>
It	O
was	O
launched	O
February	O
2006	O
under	O
BBC	B-Operating_System
Climate	I-Operating_System
Change	I-Operating_System
Experiment	I-Operating_System
branding	O
and	O
later	O
also	O
released	O
from	O
the	O
CPDN	B-Operating_System
site	O
.	O
</s>
<s>
Seasonal	B-Operating_System
Attribution	I-Operating_System
Project	I-Operating_System
-	O
This	O
is	O
a	O
high	O
resolution	O
model	O
for	O
a	O
single	O
model	O
year	O
to	O
look	O
at	O
extreme	O
precipitation	O
events	O
.	O
</s>
<s>
This	O
extra	O
resolution	O
means	O
it	O
requires	O
at	O
least	O
1.5	O
gigabytes	O
of	O
RAM	B-Architecture
.	O
</s>
<s>
It	O
uses	O
the	O
HadAM3-N144	O
climate	B-Application
model	I-Application
.	O
</s>
<s>
Myles	O
Allen	O
first	O
thought	O
about	O
the	O
need	O
for	O
large	O
climate	O
ensembles	O
in	O
1997	O
,	O
but	O
was	O
only	O
introduced	O
to	O
the	O
success	O
of	O
SETI	B-Application
@home	I-Application
in	O
1999	O
.	O
</s>
<s>
It	O
was	O
launched	O
September	O
12	O
,	O
2003	O
,	O
and	O
on	O
September	O
13	O
,	O
2003	O
,	O
the	O
project	O
exceeded	O
the	O
capacity	O
of	O
the	O
Earth	B-Device
Simulator	I-Device
to	O
become	O
the	O
world	O
's	O
largest	O
climate	B-Application
modelling	I-Application
facility	O
.	O
</s>
<s>
The	O
2003	O
launch	O
only	O
offered	O
a	O
Windows	B-Application
"	O
classic	O
"	O
client	O
.	O
</s>
<s>
On	O
26	O
August	O
2004	O
a	O
BOINC	B-Operating_System
client	O
was	O
launched	O
which	O
supported	O
Windows	B-Application
,	O
Linux	B-Application
and	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
clients	O
.	O
</s>
<s>
BOINC	B-Operating_System
has	O
stopped	O
distributing	O
classic	O
models	O
in	O
favour	O
of	O
sulfur	O
cycle	O
models	O
.	O
</s>
<s>
A	O
more	O
user	O
friendly	O
BOINC	B-Operating_System
client	O
and	O
website	O
called	O
GridRepublic	O
,	O
which	O
supports	O
climateprediction.net	B-Operating_System
and	O
other	O
BOINC	B-Operating_System
projects	O
,	O
was	O
released	O
in	O
beta	O
in	O
2006	O
.	O
</s>
<s>
By	O
November	O
2005	O
,	O
the	O
number	O
of	O
completed	O
results	O
totalled	O
45,914	O
classic	O
models	O
,	O
3,455	O
thermohaline	O
models	O
,	O
85,685	O
BOINC	B-Operating_System
models	O
and	O
352	O
sulfur	O
cycle	O
models	O
.	O
</s>
<s>
In	O
February	O
2006	O
,	O
the	O
project	O
moved	O
on	O
to	O
more	O
realistic	O
climate	B-Application
models	I-Application
.	O
</s>
<s>
The	O
BBC	B-Operating_System
Climate	I-Operating_System
Change	I-Operating_System
Experiment	I-Operating_System
was	O
launched	O
,	O
attracting	O
around	O
23,000	O
participants	O
on	O
the	O
first	O
day	O
.	O
</s>
<s>
The	O
transient	B-Application
climate	I-Application
simulation	I-Application
introduced	O
realistic	O
oceans	O
.	O
</s>
<s>
In	O
March	O
2006	O
,	O
a	O
high	O
resolution	O
model	O
was	O
released	O
as	O
another	O
project	O
,	O
the	O
Seasonal	B-Operating_System
Attribution	I-Operating_System
Project	I-Operating_System
.	O
</s>
<s>
The	O
first	O
results	O
of	O
the	O
experiment	O
were	O
published	O
in	O
Nature	O
in	O
January	O
2005	O
,	O
showing	O
that	O
with	O
only	O
slight	O
changes	O
to	O
the	O
parameters	B-Application
within	O
plausible	O
ranges	O
,	O
the	O
models	O
can	O
show	O
climate	O
sensitivities	O
from	O
less	O
than	O
2°C	O
to	O
more	O
than	O
11°C	O
.	O
</s>
<s>
For	O
example	O
,	O
by	O
Gavin	O
Schmidt	O
(	O
a	O
climate	B-Application
modeler	I-Application
with	O
the	O
NASA	O
Goddard	O
Institute	O
for	O
Space	O
Studies	O
in	O
New	O
York	O
)	O
.	O
</s>
<s>
The	O
possibility	O
of	O
such	O
high	O
sensitivities	O
being	O
plausible	O
given	O
observations	O
had	O
been	O
reported	O
prior	O
to	O
the	O
climateprediction.net	B-Operating_System
experiment	O
but	O
"	O
this	O
is	O
the	O
first	O
time	O
GCMs	B-Application
have	O
produced	O
such	O
behaviour	O
"	O
.	O
</s>
<s>
Even	O
the	O
models	O
with	O
very	O
high	O
climate	O
sensitivity	O
were	O
found	O
to	O
be	O
"	O
as	O
realistic	O
as	O
other	O
state-of-the-art	O
climate	B-Application
models	I-Application
"	O
.	O
</s>
<s>
There	O
is	O
an	O
Open	O
University	O
short	O
course	O
and	O
teaching	O
material	O
available	O
for	O
schools	O
to	O
teach	O
subjects	O
relating	O
to	O
climate	O
and	O
climate	B-Application
modelling	I-Application
.	O
</s>
<s>
The	O
original	O
experiment	O
is	O
run	O
with	O
HadSM3	O
,	O
which	O
is	O
the	O
HadAM3	B-Application
atmosphere	O
from	O
the	O
HadCM3	B-Application
model	O
but	O
with	O
only	O
a	O
"	O
slab	O
"	O
ocean	O
rather	O
than	O
a	O
full	O
dynamic	O
ocean	O
.	O
</s>
<s>
Each	O
downloaded	O
model	O
comes	O
with	O
a	O
slight	O
variation	O
in	O
the	O
various	O
model	O
parameters	B-Application
.	O
</s>
<s>
Many	O
volunteer	B-Operating_System
computing	I-Operating_System
projects	O
have	O
screensavers	B-General_Concept
to	O
visually	O
indicate	O
the	O
activity	O
of	O
the	O
application	O
,	O
but	O
they	O
do	O
not	O
usually	O
show	O
its	O
results	O
as	O
they	O
are	O
being	O
calculated	O
.	O
</s>
<s>
By	O
contrast	O
,	O
climateprediction.net	B-Operating_System
not	O
only	O
uses	O
a	O
built-in	O
visualisation	O
to	O
show	O
the	O
climate	O
of	O
the	O
world	O
being	O
modelled	O
,	O
but	O
it	O
is	O
interactive	O
which	O
allows	O
different	O
aspects	O
of	O
climate	O
(	O
temperature	O
,	O
rainfall	O
,	O
etc	O
.	O
)	O
</s>
<s>
The	O
IDL	O
Advanced	O
Visualisation	O
was	O
written	O
by	O
Andy	O
Heaps	O
of	O
the	O
University	O
of	O
Reading	O
(	O
UK	O
)	O
,	O
and	O
modified	O
to	O
work	O
with	O
the	O
BOINC	B-Operating_System
version	O
by	O
Tesella	O
Support	O
Services	O
plc	O
.	O
</s>
<s>
The	O
download	O
size	O
is	O
much	O
smaller	O
for	O
CPView	O
and	O
CPView	O
works	O
with	O
Windows	B-Device
98	I-Device
.	O
</s>
<s>
As	O
of	O
December	O
2008	O
there	O
is	O
no	O
visualisation	O
tool	O
that	O
works	O
with	O
the	O
newer	O
CPDN	B-Operating_System
models	O
.	O
</s>
<s>
So	O
users	O
can	O
only	O
visualize	O
the	O
data	O
through	O
the	O
screensaver	B-General_Concept
.	O
</s>
<s>
The	O
BBC	B-Operating_System
Climate	I-Operating_System
Change	I-Operating_System
Experiment	I-Operating_System
was	O
a	O
BOINC	B-Operating_System
project	O
led	O
by	O
Oxford	O
University	O
with	O
several	O
partners	O
including	O
the	O
UK	O
Met	O
Office	O
,	O
the	O
BBC	O
,	O
the	O
Open	O
University	O
and	O
Reading	O
University	O
.	O
</s>
<s>
It	O
is	O
the	O
transient	B-Application
coupled	I-Application
model	I-Application
of	O
the	O
climateprediction.net	B-Operating_System
project	O
.	O
</s>
<s>
On	O
8	O
March	O
2009	O
,	O
climateprediction.net	B-Operating_System
officially	O
declared	O
that	O
BBC	B-Operating_System
Climate	I-Operating_System
Change	I-Operating_System
Experiment	I-Operating_System
was	O
finished	O
,	O
before	O
shutting	O
down	O
the	O
project	O
.	O
</s>
