<s>
The	O
FLEXible	O
PARTicle	O
dispersion	O
model	O
(	O
FLEXPART	B-Application
)	O
is	O
a	O
Lagrangian	O
Particle	O
Dispersion	O
Model	O
used	O
to	O
simulate	O
air	O
parcel	O
trajectories	O
.	O
</s>
<s>
FLEXPART	B-Application
has	O
inherited	O
large	O
portions	O
of	O
its	O
code	O
from	O
its	O
predecessor	O
,	O
FLEXTRA	O
(	O
FLEXible	O
TRAjectory	O
model	O
)	O
.	O
</s>
<s>
The	O
first	O
version	O
of	O
FLEXPART	B-Application
was	O
released	O
in	O
1998	O
and	O
was	O
considered	O
free	B-Application
software	I-Application
.	O
</s>
<s>
In	O
addition	O
to	O
main	O
FLEXPART	B-Application
code	O
,	O
several	O
branches	O
have	O
been	O
developed	O
for	O
use	O
with	O
mesoscale	O
meteorological	O
models	O
.	O
</s>
<s>
In	O
particular	O
,	O
FLEXPART-WRF	O
was	O
created	O
to	O
work	O
with	O
the	O
open	O
source	O
WRF	B-Application
model	I-Application
.	O
</s>
<s>
The	O
first	O
version	O
of	O
FLEXPART-WRF	O
was	O
presented	O
in	O
2006	O
by	O
Jerome	O
D	O
.	O
Fast	O
and	O
Richard	O
C	O
.	O
Easter	O
.	O
</s>
<s>
The	O
model	O
was	O
later	O
renamed	O
the	O
"	O
PNNL	O
Integrated	O
Lagrangian	O
Transport	O
"	O
(	O
PILT	O
)	O
model	O
since	O
the	O
code	O
base	O
started	O
to	O
deviate	O
extensively	O
from	O
the	O
main	O
FLEXPART	B-Application
branch	O
.	O
</s>
<s>
In	O
2007	O
,	O
a	O
new	O
technical	O
report	O
was	O
presented	O
where	O
the	O
model	O
was	O
once	O
again	O
referred	O
to	O
as	O
FLEXPART-WRF	O
.	O
</s>
<s>
At	O
this	O
time	O
,	O
there	O
were	O
still	O
a	O
number	O
of	O
important	O
features	O
missing	O
in	O
FLEXPART-WRF	O
(	O
which	O
were	O
available	O
in	O
FLEXPART	B-Application
)	O
.	O
</s>
<s>
A	O
number	O
of	O
research	O
groups	O
started	O
developing	O
FLEXPART-WRF	O
on	O
their	O
own	O
,	O
in	O
2011	O
,	O
there	O
were	O
three	O
separate	O
projects	O
on	O
GitHub	B-Application
,	O
each	O
with	O
a	O
partial	O
goal	O
to	O
implement	O
a	O
scheme	O
for	O
wet	O
deposition	O
.	O
</s>
<s>
In	O
2013	O
,	O
a	O
major	O
update	O
of	O
FLEXPART-WRF	O
was	O
released	O
with	O
support	O
from	O
the	O
FLEXPART	B-Application
developers	O
,	O
the	O
release	O
included	O
a	O
working	O
wet	O
deposition	O
scheme	O
as	O
well	O
as	O
new	O
run-time	O
options	O
for	O
wind	O
fields	O
and	O
turbulence	O
.	O
</s>
<s>
The	O
code	O
was	O
also	O
parallelized	O
with	O
compile-time	O
options	O
for	O
OpenMP	B-Application
and	O
MPI	B-Application
added	O
to	O
the	O
previous	O
default	O
serial	O
mode	O
.	O
</s>
<s>
Furthermore	O
,	O
an	O
option	O
to	O
use	O
the	O
NetCDF	B-Application
standard	O
format	O
for	O
output	O
was	O
added	O
.	O
</s>
