4 international gnss service (igs) troposphere products ......international gnss service (igs)...
TRANSCRIPT
Inte
rnati
on
al G
NS
S S
erv
ice (
IGS
)
Tro
po
sp
here
Pro
du
cts
an
d W
ork
ing
Gro
up
Acti
vit
ies
C H
ackm
an
1, G
uerg
an
a G
uero
va
2,
S B
yra
m1,
J D
ou
sa
3 a
nd
U H
ug
en
tob
ler4
1U
nited S
tate
s N
aval O
bserv
ato
ry,
Washin
gto
n, D
C U
SA
2S
ofia U
niv
ers
ity,
Sofia,
Bulg
aria
3G
eodetic O
bserv
. P
ecný,
Czech R
epublic
4T
echnis
che U
niv
ers
ität M
ünchen
, M
unic
h, G
erm
any
guero
va@
phys.u
ni-sofia.b
g
christine.h
ackm
an@
usno.n
avy.m
il
2
FIG
Work
ing W
eek 2
015 P
aper
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ofia, B
ulg
aria; 18 M
ay 2
015
Agenda
•IG
S o
verv
iew
: m
issio
n,
receiv
er
netw
ork
•W
hy I
GS
estim
ate
s t
roposphere
dela
y
•IG
S F
inal T
roposphere
Estim
ate
s:
genera
tion,
usage
•IG
S T
roposphere
Work
ing G
roup:
str
uctu
re, m
eetings,
pro
jects
, how
to join
3
FIG
Work
ing W
eek 2
015 P
aper
7696
S
ofia, B
ulg
aria; 18 M
ay 2
015
IGS
overv
iew
(fo
unded 1
994)
•M
issio
n:
•pro
vid
e h
ighe
st-
qualit
y G
NS
S d
ata
, pro
ducts
, se
rvic
es…
•in
supp
ort
of applic
ations b
ene
fiting s
cie
nce, so
cie
ty (
e.g
.,
terr
estr
ial re
fere
nce fra
me, P
NT
, eart
h-s
cie
nce r
ese
arc
h)…
•openly
-availa
ble
basis
•A
ctivitie
s:
•co
ord
inate
glo
ba
l G
NS
S-r
ece
iver
netw
ork
, arc
hiv
ing o
f its d
ata
•pro
duce e
stim
ate
s fro
m those
data
: G
NS
S s
ate
llite
orb
its,
receiv
er
coord
inate
s, eart
h r
ota
tion p
ara
mete
rs, sat/re
ceiv
er
clo
ck
valu
es, io
no
/tro
po
valu
es…
•w
ork
ing g
roups: im
pro
ve s
cie
nce to im
pro
ve e
stim
ate
s
•T
o learn
more
: htt
p:/
/igs.o
rg
4
FIG
Work
ing W
eek 2
015 P
aper
7696
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ofia, B
ulg
aria; 18 M
ay 2
015
IGS
receiv
er
netw
ork
, data
analy
sis
•400+
perm
anent
continuously
-
opera
ting d
ual-
frequency c
arr
ier-
phase r
eceiv
ers
•R
ecord
one o
r m
ore
of:
GP
S, G
LO
, G
AL,
BeiD
ou,
QZ
SS
,
SB
AS
•D
ata
arc
hiv
es
(public
ly-a
ccessib
le):
•F
our
glo
bal IG
S
data
cente
rs
•R
egio
nal data
cente
rs
•IG
S a
naly
sis
cente
rs p
rocess m
easure
ments
, contr
ibute
“pro
ducts
” (e
.g.,
orb
its)
to I
GS
AC
Coord
inato
r, w
ho
pro
duces o
ffic
ial IG
S p
roducts
:
•ultra
s (
NR
T);
rapid
s (
24
-h late
r);
finals
(best)
5
FIG
Work
ing W
eek 2
015 P
aper
7696
S
ofia, B
ulg
aria; 18 M
ay 2
015
Why IG
S e
stim
ate
s tro
po
sp
he
re d
ela
y
•O
rigin
al re
ason:
“nuis
ance p
ara
mete
r” –
must estim
ate
to
achie
ve c
m-
or
mm
-level G
NS
S p
ositio
nin
g
•2.2
m @
ze
nith; te
ns o
f m
@ low
ele
vation (
e.g
., 1
5 o
r 7 d
eg
)
•Z
TD
GN
SS =
ZT
Ddry +
ZT
Dw
et
•Z
TD
dry:
~2
m, ca
n m
odel
•Z
TD
wet:
0.1
-0.2
5 m
, ch
ange
s too q
uic
kly
/locally
to m
odel ->
must
estim
ate
fro
m G
NS
S o
r get fr
om
, e.g
., W
VR
•B
ut
now
: use Z
TD
GN
SS -
> Z
TD
wet ->
PW
V
•A
tmospheric s
cie
nce!
•L
ow
-late
ncy, hig
h-d
ensity P
WV
: w
eath
er
fore
casting
•D
eca
des-l
ong r
eco
rd, 300+
sites w
orldw
ide, valu
es e
very
fiv
e
min
ute
s: clim
ate
stu
die
s
6
FIG
Work
ing W
eek 2
015 P
aper
7696
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ofia, B
ulg
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ay 2
015
IGS
Fin
al T
roposphere
Estim
ate
s
•U
SN
O/D
r S
Byra
m g
ene
rate
s
•O
ne 2
4 h
r file
per
IGS
sta
tion
•
ZT
D,
gra
die
nts
every
5 m
in
•325
-6 s
tations/d
, 2013-4
•C
om
pute
d u
sin
g B
ern
ese G
PS
S
W, G
MF
, P
PP
usin
g IG
S F
inal
Orb
its/E
OP
s/S
V c
locks
•T
hus ~
21 d
late
ncy
•U
sed b
y s
cie
ntific r
esearc
hers
as r
efe
rence (
e.g
. W
an
g e
t al.
2013
* ra
dio
sonde
stu
dy)
•12.3
M d
ow
nlo
ad
s in 2
014
•ftp://c
ddis
.gsfc
.nasa.g
ov/g
ps/p
roducts
/tro
posphere
/zpd
Num
ber
of
qualit
y-c
hecked IG
S F
inal
Tro
posp
here
Estim
ate
file
s s
ubm
itte
d t
o
IGS
per
measure
ment
day.
20
0
25
0
30
0
35
0
40
0
03
65
73
01
09
51
46
0
# receivers for which files submitted
da
ys
sin
ce 1
Ja
n 2
01
1
Nu
mb
er,
QC
-ed
Tro
po
Fil
es
Su
bm
itte
d t
o I
GS
20
11
me
an
: 3
22
20
12
me
an
: 3
02
20
13
me
an
: 3
25
20
14
me
an
: 3
26
improvedresults screening
update station list
*Wang, J.
et a
l.,
“Ra
dia
tion d
ry b
ias c
orr
ectio
n o
f V
ais
ala
RS
92
hu
mid
ity d
ata
an
d its
im
pa
cts
on
his
torica
l
rad
ioso
nde
da
ta,”
J A
tmo
sp
h a
nd
Oce
an
ic T
ech
, 3
0:1
97-2
14, 2
01
3.
Exam
ple
: IG
S F
inal Z
TD
, 29 J
une 2
012
CE
DU
DA
V1
KO
KB
PO
L2
TH
U3
U
SN
3
19
00
20
00
21
00
22
00
23
00
24
00
25
00
26
00
00
.25
0.5
0.7
51
MM
FR
AC
TIO
N O
F D
AY
TO
TAL
ZE
NIT
H T
RO
PO
SP
HE
RE
DE
LAY,
30
JU
NE
20
12
CE
DU
DA
V1
KO
KB
PO
L2T
HU
3U
SN
3
FIG
Work
ing W
eek 2
015 P
aper
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ofia, B
ulg
aria; 18 M
ay 2
015
7
8
FIG
Work
ing W
eek 2
015 P
aper
7696
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ofia, B
ulg
aria; 18 M
ay 2
015
Usin
g I
GS
FT
Es:
su
btleties
•“R
epro
cessin
g”
cam
paig
ns:
•IG
S a
dop
ts n
ew
physic
al m
odels
->
ch
ange
s Z
TD
estim
ate
s
(thoug
h s
am
e a
tmosph
ere
) ->
co
mplic
ate
s long
-term
stu
die
s
•T
o a
ddre
ss: re
pro
cess e
ntire
tim
espan o
f IG
S G
NS
S
measure
ments
usin
g o
ne, best-
to-d
ate
model se
t
•“R
epro
1”:
ftp
://c
ddis
.gsfc
.nasa.g
ov/g
ps/p
roducts
/zpd/r
epro
1
•“R
epro
2”:
will
do w
hen R
epro
2 o
rbits/c
locks/E
OP
s c
om
ple
te
•U
pcom
ing im
pro
vem
ents
to I
GS
FT
Es:
•R
educe d
ay-b
oun
dary
dis
co
ntinuitie
s (
no
n-p
hysic
al fe
w-m
m Z
TD
-
valu
e jum
ps b
etw
ee
n e
nd o
f one 2
4-h
r file
, begin
nin
g o
f next)
•U
pgra
de to n
ew
er
vers
ion o
f B
ern
ese S
W, new
er
models
IGS
Tro
po
sphere
Work
ing
Gro
up
lM
issio
n:
impro
ve a
ccura
cy,
usabili
ty o
f G
NS
S
troposphere
estim
ate
s
lM
em
bers
: 50+
worldw
ide;
all
are
welc
om
e!
lT
wo m
eetings/y
r (s
imulc
ast
usin
g g
oto
meeting.c
om
):
lD
ece
mber:
sp
linte
r @
Am
. G
eophysic
al U
nio
n F
all
Meeting
lS
pring/S
um
mer:
either
IGS
Work
shop o
r sp
linte
r @
EG
U
lM
ajo
r activitie
s:
lW
ork
ing g
roup p
roje
cts
(n
ext page
).
lC
oord
inate
techn
ica
l se
ssio
ns (
ple
nary
, poste
r) a
t IG
S W
ork
sho
p.
lP
lenary
: th
ree o
ral pre
senta
tions,
big
-pic
ture
pro
jects
lP
oste
r: g
oal =
foste
r te
chnic
al exchange -
> s
eek m
axim
um
part
icip
ation
lLin
ks t
o 2
014 I
GS
Work
shop
contr
ibutions in p
rinte
d v
ers
ion o
f th
is p
resenta
tion
FIG
Work
ing W
eek 2
015 P
aper
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ulg
aria; 18 M
ay 2
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9
IGS
TW
G p
roje
cts
FIG
Work
ing W
eek 2
015 P
aper
7696
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ofia, B
ulg
aria; 18 M
ay 2
015
10
Auto
mate
d,
continuous c
om
pari
sons o
f
tropo e
stim
ate
s f
rom
independe
nt
techniq
ues (
GN
SS
, V
LB
I, r
adio
sondes…
)
•C
om
pari
son o
f answ
ers
yie
lds b
ett
er
uncert
ain
ty e
stim
ate
s -
> im
pro
ves
accura
cy
•P
rim
ary
develo
pm
en
t @
GO
P;
contr
ibu
tions f
rom
GF
Z,
US
NO
, m
ore
•P
art
ially
fundin
g,
CZ
-US
Konta
kt
II
gra
nt
# L
H14089
•C
om
ple
te 2
016
clic
k-a
ble
sta
tion m
ap
, lis
t
gra
phs u
p t
o s
ix
sta
tions w
ith
multip
le
techniq
ue
com
parisons
user
defined
com
parison
gra
ph
Supp
ort
of
trop
o_
sin
ex (
ZT
D-d
issem
ination)
form
at
sta
ndard
ization
•A
d-h
oc f
orm
at
evolu
tion in d
iffe
rent
geodetic
com
munitie
s
•IG
S T
ropo
WG
mem
bers
R P
acio
ne
, J D
ousa
spearh
eadin
g C
OS
T A
ction G
NS
S4S
WE
C
WG
3 e
ffort
to r
edefin
e/e
xpand f
orm
at
•S
tatu
s:
just
sta
rted F
all
2014
11
FIG
Work
ing W
eek 2
015 P
aper
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ofia, B
ulg
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ay 2
015
Conclu
sio
n: jo
in u
s!
Fo
r m
ore in
form
ati
on
on
…
•IG
S: http://igs.o
rg
•IG
S F
inal T
rop
osphere
Estim
ate
s:
•D
ow
nlo
ad h
ere
: ftp://c
ddis
.gsfc
.nasa.g
ov/g
ps/p
roducts
/tro
posph
ere
/zpd
•Q
uestions a
bout
them
?
•D
r S
ha
ryl B
yra
m:
sh
ary
l.b
yra
m@
usn
o.n
avy.m
il
•D
r C
hri
stin
e H
ackm
an
: ch
ristin
e.h
ackm
an
@usno
.na
vy.m
il
•IG
S T
rop
osphere
Work
ing G
roup:
•Q
uestions:
christine.h
ackm
an@
usno.n
avy.m
il
•W
ebsite (
under
develo
pm
ent)
: http://igs.o
rg/p
roje
cts
-work
ing
-gro
ups/tw
g
•Join
em
ail
list: h
ttp://igscb.jpl.nasa.g
ov/m
ailm
an/igs-t
wg
Tha
nk y
ou f
or
your
att
ention!
Extr
a s
tuff
(as n
eeded?)
FIG
Work
ing W
eek
2015 P
aper
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ulg
aria; 18 M
ay 2
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12
13
FIG
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ing W
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ofia, B
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Exam
ple
:
Gra
die
nt of 1
mm
asym
metr
y o
f
1 m
m a
t z=
38
asym
metr
y
15 m
m a
t
z=
75
tilt o
f 1.5
′
pro
jection o
f ze
nith
dela
y v
ecto
r: 1
mm
Tro
posphere
Gra
die
nts
hydro
sta
tic
dela
y
(mod
elle
d)
wet dela
y
(estim
ate
d)
NS
and E
W
gra
die
nts
(estim
ate
d)
sla
nt dela
y
(mea
su
red)