CIRCULAR T 357 ISSN 1143-1393
2017 OCTOBER 10, 13h UTC
BUREAU INTERNATIONAL DES POIDS ET MESURES
ORGANISATION INTERGOUVERNEMENTALE DE LA CONVENTION DU METRE
PAVILLON DE BRETEUIL F-92312 SEVRES CEDEX TEL. +33 1 45 07 70 70 FAX. +33 1 45 34 20 21 tai@bipm.org

The contents of the sections of BIPM Circular T are fully described in the document " Explanatory supplement to BIPM Circular T " available at ftp://ftp2.bipm.org/pub/tai/publication/notes/explanatory_supplement_v0.1.pdf

1 - Difference between UTC and its local realizations UTC(k) and corresponding uncertainties. From 2017 January 1, 0h UTC, TAI-UTC = 37 s.
Date 2017 0h UTC AUG 29 SEP 3 SEP 8 SEP 13 SEP 18 SEP 23 SEP 28 Uncertainty/ns Notes
MJD 57994 57999 58004 58009 58014 58019 58024 uA uB u
Laboratory k [UTC-UTC(k)]/ns
AOS (Borowiec) -2.6 -3.6 -4.5 -4.3 -4.0 -4.2 -4.1 0.6 3.0 3.0
APL (Laurel) 1.6 -2.9 -2.2 -1.8 -2.8 -2.8 -2.7 0.4 10.9 10.9
AUS (Sydney) 436.8 428.0 411.4 413.3 413.1 405.2 387.6 0.4 5.9 5.9
BEV (Wien) 36.2 36.8 36.9 22.7 24.4 22.3 11.1 0.4 2.8 2.8
BIM (Sofiya) 6864.7 6893.9 6941.7 6995.9 7064.0 7121.9 7137.2 0.7 3.0 3.1
BIRM (Beijing) 37.7 33.5 28.6 31.8 34.3 33.3 30.3 0.7 2.8 2.9
BOM (Skopje) -839.4 -837.9 -834.4 -836.4 -833.0 -841.0 -842.1 0.4 3.0 3.0
BY (Minsk) -0.6 -0.5 -0.9 -1.4 3.0 6.6 3.6 1.5 9.3 9.4
CAO (Cagliari) - - - - - - -
CH (Bern-Wabern) 27.9 25.9 22.3 21.7 21.3 23.4 27.9 0.4 1.9 1.9
CNES (Toulouse) 27.3 28.6 31.8 32.5 27.9 25.1 23.2 0.4 4.3 4.3
CNM (Queretaro) -1.1 -4.8 -1.1 3.1 -4.4 -0.1 -0.4 2.5 11.1 11.4
CNMP (Panama) -41.5 -35.5 -22.7 15.2 24.4 23.9 21.3 0.6 7.2 7.2
DFNT (Tunis) 19872.3 20054.3 20250.8 20458.3 20650.9 20834.1 21007.3 0.7 20.0 20.1
DLR (Oberpfaffenhofen) 44.4 43.8 45.2 53.7 69.2 238.6 285.0 0.7 3.0 3.1 (1)
DMDM (Belgrade) -0.8 -2.9 3.9 13.0 7.0 14.3 13.8 0.4 2.8 2.8
DTAG (Frankfurt/M) 29.7 38.7 39.9 34.8 31.3 25.3 21.5 0.4 2.8 2.8
EIM (Thessaloniki) -77.7 - - - 14.4 6.3 8.6 4.0 11.3 12.0
ESTC (Noordwijk) -0.8 -0.3 2.3 3.0 4.3 5.7 5.0 0.4 2.8 2.8
HKO (Hong Kong) 1054.0 1069.5 1079.3 1087.7 1097.9 1113.6 1125.8 0.4 7.4 7.4
ICE (San Jose) 45.5 22.5 16.1 10.8 0.3 -17.5 2.5 0.4 7.2 7.2 (2)
IFAG (Wettzell) -947.2 -938.2 -934.8 -931.5 -934.4 -931.8 -935.3 1.0 5.9 6.0
IMBH (Sarajevo) 13.5 -3.1 7.8 3.5 4.4 1.3 2.7 0.4 7.1 7.1
INCP (Lima) 120.2 129.9 128.5 120.9 121.7 122.0 117.7 5.0 20.0 20.7
INM (Bogota D.C.) -15.2 -17.5 -15.9 -18.0 -10.2 5.9 12.1 2.5 20.0 20.2
INPL (Jerusalem) -19.9 -20.1 -23.0 -30.5 -36.2 -40.1 -51.9 0.4 7.1 7.1
INTI (Buenos Aires) 2.7 -1.2 3.4 6.4 5.3 7.7 23.7 2.5 20.0 20.2
INXE (Rio de Janeiro) -7.5 -6.1 -13.1 -7.3 -0.5 -5.9 -7.0 0.4 20.0 20.0
IT (Torino) -5.1 -4.8 -4.5 -3.9 -3.2 -3.2 -2.9 0.4 1.6 1.6
JATC (Lintong) 3.2 4.8 3.3 4.6 3.8 2.1 2.6 0.4 10.2 10.2
JV (Kjeller) 4.8 -6.2 -17.2 -16.6 -17.6 -19.0 -19.6 0.4 20.0 20.0
KEBS (Nairobi) - - - - - - -
KIM (Serpong-Tangerang) 141.1 168.3 169.5 174.4 188.4 200.4 173.8 2.0 20.0 20.1
KRIS (Daejeon) 35.5 40.3 44.3 47.7 50.6 52.2 52.9 0.4 11.1 11.1
KZ (Astana) -294.7 -322.8 -334.3 -331.1 -313.3 -298.9 -301.0 1.5 9.3 9.4
LT (Vilnius) 158.7 144.0 145.4 157.0 152.5 168.8 181.8 2.0 11.3 11.4
MASM (Bayanzurkh) -411.6 -428.7 -451.6 - - -34.5 -60.0 0.7 20.0 20.1
MBM (Podgorica) 51657.3 51989.6 52323.7 52643.4 52978.9 53335.9 53658.6 1.5 20.0 20.1
MIKE (Espoo) -0.4 -0.3 0.5 0.5 0.8 -0.2 -0.7 0.7 4.2 4.3
MKEH (Budapest) -65005.0 -65222.3 -65420.4 -65627.5 -65836.7 -66030.7 -66237.0 1.5 20.0 20.1
MSL (Lower Hutt) 285.3 289.9 309.0 301.6 285.8 300.7 321.8 1.5 20.0 20.1
MTC (Makkah) 1149.2 1164.1 1145.4 1170.6 1149.7 1204.2 1187.0 10.0 7.4 12.4
NAO (Mizusawa) 99.4 86.1 93.0 95.8 97.0 89.5 75.7 2.0 20.0 20.1
NICT (Tokyo) -5.7 -5.8 -7.5 -6.9 -5.9 -4.2 -1.9 0.4 2.2 2.3
NIM (Beijing) 5.2 4.5 3.8 3.3 3.9 3.7 2.9 0.7 1.9 2.0
NIMB (Bucharest) 1813.1 1816.1 1803.5 1816.4 1818.9 1814.2 1808.5 0.4 7.2 7.2
NIMT (Pathumthani) 203.3 208.9 214.5 217.7 219.5 218.6 221.5 1.0 20.0 20.1
NIS (Cairo) 11.9 8.4 2.4 -19.9 -30.1 -48.5 -55.3 1.6 20.0 20.1
NIST (Boulder) 0.5 0.6 1.1 1.7 2.2 2.2 1.4 0.4 4.9 4.9
NMIJ (Tsukuba) 8.8 8.1 6.7 5.8 5.3 4.1 3.0 0.4 2.8 2.8
NMLS (Sepang) 537.9 586.5 646.6 685.8 731.0 781.9 829.3 1.0 20.0 20.1
NPL (Teddington) 0.7 -0.8 -0.3 0.2 1.8 2.1 3.1 0.4 2.8 2.8
NPLI (New-Delhi) 7.8 8.1 11.4 14.7 16.0 14.3 9.7 0.4 19.9 19.9
NRC (Ottawa) 45.3 44.2 43.4 49.4 52.5 45.2 44.7 0.4 2.8 2.8
NRL (Washington DC) -30.1 0.9 24.1 12.2 -7.8 5.3 - 0.4 20.0 20.0
NTSC (Lintong) 1.8 3.4 0.6 1.7 1.1 -0.5 -0.2 0.4 2.0 2.1
ONBA (Buenos Aires) -2211.9 -2225.2 -2225.0 -2231.1 -2230.4 -2208.7 -2225.0 2.5 11.3 11.5
ONRJ (Rio de Janeiro) 1.5 0.8 3.2 5.4 4.3 5.2 1.7 1.0 7.7 7.7
OP (Paris) 1.1 1.5 1.8 2.0 2.3 2.7 2.7 0.4 1.4 1.5
ORB (Bruxelles) 0.9 1.0 1.0 1.3 2.2 2.0 1.9 0.4 5.5 5.5
PL (Warszawa) 3.2 9.8 13.1 5.8 8.5 7.3 10.8 0.4 3.4 3.4
PTB (Braunschweig) -0.3 0.1 0.5 1.0 1.4 1.5 1.5 0.2 1.2 1.3
ROA (San Fernando) 5.9 4.6 2.9 3.7 4.1 2.0 0.5 0.4 1.5 1.5
SASO (Riyadh) -603.0 -603.9 -610.3 -616.8 -623.6 -622.2 -621.9 0.4 7.4 7.4
SCL (Hong Kong) 43.3 29.1 28.7 31.8 26.8 20.9 21.5 6.0 14.1 15.4
SG (Singapore) 6.1 3.3 0.0 -2.1 -0.3 -0.1 3.1 0.7 5.9 5.9
SIQ (Ljubljana) 264.6 274.9 281.4 297.8 314.0 318.7 323.9 0.4 7.4 7.4
SMD (Bruxelles) -2.1 -1.2 2.7 5.0 12.4 8.0 2.5 0.4 7.7 7.7
SMU (Bratislava) -1399.3 -1404.5 -1408.4 -1415.6 -1423.3 -1432.3 -1449.4 1.5 12.3 12.4
SP (Boras) 4.3 2.9 2.3 1.9 1.6 1.2 0.9 0.4 1.4 1.5
SU (Moskva) 5.6 5.3 5.7 5.3 4.4 4.3 2.5 1.3 6.1 6.2
TL (Chung-Li) -1.2 -1.9 -2.8 -2.3 0.6 1.6 3.1 0.4 2.2 2.2
TP (Praha) -29.0 -17.8 -20.9 -26.9 -23.3 -17.0 -5.2 0.4 6.5 6.5
UA (Kharkov) 2.1 1.0 -4.5 3.6 3.4 -2.5 -1.1 1.5 8.7 8.8
UAE (Abu Dhabi) 12.2 11.3 16.9 16.1 24.4 19.6 19.1 4.0 8.2 9.1
UME (Gebze-Kocaeli) -2251.0 -2293.7 -2340.6 -2402.7 -2455.1 -2503.7 -2560.9 0.7 3.0 3.1
USNO (Washington DC) 1.7 1.8 2.2 2.6 3.0 2.7 2.2 0.3 1.4 1.5
VMI (Ha Noi) 20.7 29.3 18.8 12.5 8.7 -5.3 -14.0 1.3 20.0 20.1
VSL (Delft) 11.0 17.0 22.8 24.0 14.7 24.4 13.3 0.4 1.6 1.6
ZA (Pretoria) 6.0 7.3 5.8 2.5 1.5 4.0 7.5 0.4 4.2 4.2
- Notes on section 1:
(1) DLR : Time step of UTC(DLR) of about -125 ns on MJD 58015.61
(2) ICE : Time step of UTC(ICE) of 27.6 ns on MJD 57999 due to calibration

2 - Difference between the normalized frequencies of EAL and TAI.
Interval of validity f(EAL)-f(TAI)
Steering correction 57994 - 58024 6.501x10-13 (2017 AUG 29 - 2017 SEP 28)
New correction 58024 - 58054 6.501x10-13 (2017 SEP 28 - 2017 OCT 28)
New correction foreseen 58054 - 58084 6.501x10-13 (2017 OCT 28 - 2017 NOV 27)

3 - Duration of the TAI scale interval d.

Table 1: Estimate of d by individual PSFS measurements and corresponding uncertainties.
All values are expressed in 10-15 and are valid only for the stated period of estimation.
Standard Period of d uA uB ul/lab ul/Tai u uSrep Ref(uS) Ref(uB) uB(Ref) Steer Note
Estimation
PTB-CS1 57994 58024 -5.51 6.00 8.00 0.00 0.17 10.00 PFS/NA T148 8. Y (1)
PTB-CS2 57994 58024 -6.40 3.00 12.00 0.00 0.17 12.37 PFS/NA T148 12. Y (1)
IT-CsF2 58004 58024 -0.03 0.62 0.17 0.30 0.38 0.80 PFS/NA T315 0.19 Y (2)
PTB-CSF1 58004 58024 0.12 0.07 0.38 0.02 0.19 0.43 PFS/NA T162 1.40 Y (3)
PTB-CSF2 57994 58024 -0.42 0.10 0.20 0.10 0.17 0.30 PFS/NA T287 0.41 Y (3)

Notes:
(1) Continuously operating as a clock participating to TAI
(2) Report 02 OCT. 2017 by INRIM
(3) Report 29 SEP. 2017 by PTB

Table 2: Estimate of d by the BIPM based on all PSFS measurements identified to be used for TAI steering
over the period MJD57634-58024, and corresponding uncertainties.

Period of estimation d u
57994-58024 -0.22x10-15 0.22x10-15 (2017 AUG 29 - 2017 SEP 28)

4 - Relations of UTC and TAI with predictions of UTC(k) disseminated by GNSS.

[UTC-UTC(USNO)_GPS] = C0', [TAI-UTC(USNO)_GPS] = 37 s + C0'
[UTC-UTC(SU)_GLONASS]= C1', [TAI-UTC(SU)_GLONASS]= 37 s + C1'

For this edition of Circular T, σ0'= 1.1 ns, σ1'= 6.6 ns

2017 0h UTC MJD C0'/ns N0 C1'/ns N1'
AUG 29 57994 -1.3 89 25.8 89
AUG 30 57995 -0.9 87 25.0 86
AUG 31 57996 -2.4 89 26.0 80
SEP 1 57997 -2.0 80 28.5 90
SEP 2 57998 -1.1 89 28.8 81
SEP 3 57999 -1.5 89 24.7 85
SEP 4 58000 -1.1 89 22.5 89
SEP 5 58001 -2.0 89 22.1 85
SEP 6 58002 -1.4 89 22.2 79
SEP 7 58003 -2.6 89 24.2 89
SEP 8 58004 -1.0 89 23.3 87
SEP 9 58005 -0.9 90 22.1 89
SEP 10 58006 -1.3 89 23.4 79
SEP 11 58007 -1.1 89 24.3 85
SEP 12 58008 -1.0 84 21.3 89
SEP 13 58009 -0.7 90 19.7 90
SEP 14 58010 -1.7 89 20.8 86
SEP 15 58011 -2.6 89 20.2 88
SEP 16 58012 -0.5 89 19.0 87
SEP 17 58013 -0.3 90 20.5 89
SEP 18 58014 0.1 89 21.7 76
SEP 19 58015 -0.2 89 23.1 88
SEP 20 58016 -0.2 86 24.0 89
SEP 21 58017 0.1 87 22.8 89
SEP 22 58018 -1.5 89 22.7 89
SEP 23 58019 -0.4 89 22.8 89
SEP 24 58020 -1.4 89 23.1 88
SEP 25 58021 -0.9 90 23.5 89
SEP 26 58022 -0.6 89 22.0 80
SEP 27 58023 -1.8 89 21.1 87
SEP 28 58024 -2.4 89 20.7 89

5 - Time links used for the computation of TAI, calibrations information and corresponding uncertainties.

Link Type Equipment Cal_ID1 / Cal_ID2 uStb/ns uCal/ns uAg/ns Al/ns YYMM
APL /PTB GPSPPP AP02 /PT02 NA_Al / 1001-2016 0.3 11.2 10 24.3 1511
AUS /PTB GPSPPP AU01 /PT02 1002-2010 / 1001-2016 0.3 5.8 3
BEV /PTB GPSPPP BE1_ /PT02 1012-2016 / 1001-2016 0.3 2.5 0
BIM /PTB GPS P3 BM37 /PT02 1011-2016 / 1001-2016 0.7 2.7 1
BIRM/PTB GPS P3 BI01 /PT02 1015-2016 / 1001-2016 0.7 2.5 0
BOM /PTB GPSPPP MABM /PT02 1011-2016 / 1001-2016 0.3 2.7 1
BY /PTB GPS MC BY46 /PT07 NA / 1001-2016 1.5 9.2 6
CAO /PTB NL
CNES/PTB GPSPPP CS22 /PT02 1101-2016 / 1001-2016 0.3 4.1 1
CNM /PTB GPS MC CN00 /PT07 NA_Al / 1001-2016 2.5 11.2 10 -27.3 0804
CNMP/PTB GPSPPP MP1_ /PT02 NA_Al / 1001-2016 0.5 7.1 1 41.7 1607
DFNT/PTB GPS P3 DN__ /PT02 NC_Al / 1001-2016 0.7 20.0 10.3 1507
DLR /PTB GPS P3 DL05 /PT02 1012-2016 / 1001-2016 0.7 2.7 1
DMDM/PTB GPSPPP ZM68 /PT02 1011-2016 / 1001-2016 0.3 2.5 0
DTAG/PTB GPSPPP DT04 /PT02 1015-2017 / 1001-2016 0.3 2.5 0
EIM /PTB GPS MC EI__ /PT07 1011-2007 / 1001-2016 4.0 11.2 10
ESTC/PTB GPSPPP ES04 /PT02 1019-2016 / 1001-2016 0.3 2.5 0
HKO /PTB GPSPPP HKO1 /PT02 NA_Al / 1001-2016 0.3 7.3 2 +15.9 1304
ICE /PTB GPSPPP CE__ /PT02 NA_Al / 1001-2016 0.3 7.1 1 27.6 1709
IFAG/PTB GPS P3 IF19 /PT02 NA_Al / 1001-2016 1.0 5.8 3
IMBH/PTB GPSPPP BH01 /PT02 2004-2016 / 1001-2016 0.3 7.0 0
INCP/PTB GPS MC CP__ /PT07 NC / 1001-2016 5.0 20.0
INM /PTB GPS MC IC__ /PT07 NC / 1001-2016 2.5 20.0
INPL/PTB GPSPPP IL05 /PT02 2002-2016 / 1001-2016 0.3 7.0 0
INTI/PTB GPS MC IN__ /PT07 NC / 1001-2016 2.5 20.0
INXE/PTB GPSPPP NXRA /PT02 NC / 1001-2016 0.3 20.0
JV /PTB GPSPPP JV01 /PT02 NC_Al / 1001-2016 0.3 20.0 130.0 1509
KEBS/PTB NL
KIM /PTB GPS MC KI02 /PT07 NC_Al / 1001-2016 2.0 20.0 -30.6 0901
KRIS/PTB GPSPPP KR01 /PT02 1003-2005 / 1001-2016 0.3 11.2 10
KZ /PTB GPS MC KZ01 /PT07 2002-2008 / 1001-2016 1.5 9.2 6
LT /PTB GPS MC LT01 /PT07 1007-2006 / 1001-2016 2.0 11.2 10
MASM/PTB GPS P3 MN__ /PT02 NC / 1001-2016 0.7 20.0
MBM /PTB GPS MC MEBM /PT07 NC / 1001-2016 1.5 20.0
MIKE/PTB GPS P3 MI04 /PT02 1102-2015 / 1001-2016 0.7 4.1 1
MKEH/PTB GPS MC MK01 /PT07 NC / 1001-2016 1.5 20.0
MSL /PTB GPS P3 MS0_ /PT02 NC / 1001-2016 1.5 20.0
MTC /PTB GPS P3 MC02 /PT02 NA_Al / 1001-2016 10.0 7.3 2 32.6 1411
NAO /PTB GPS MC NAT2 /PT07 NC / 1001-2016 2.0 20.0
NICT/PTB GPSPPP NC01 /PT02 1001-2016 / 1001-2016 0.3 2.0 1
NIM /PTB GPS P3 IM06 /PT02 1001-2016 / 1001-2016 0.7 1.5 0
NIMB/PTB GPSPPP MB02 /PT02 NA_Al / 1001-2016 0.3 7.1 1 32.2 1611
NIMT/PTB GPS P3 MTTO /PT02 NC / 1001-2016 1.0 20.0
NIS /PTB GPS P3 IS__ /PT02 NC_Al / 1001-2016 1.6 20.0 +16.4 1303
NMIJ/PTB GPSPPP NM0D /PT02 NA_Al / 1001-2016 0.3 2.6 2
NMLS/PTB GPS P3 LSM1 /PT02 NC_Al / 1001-2016 1.0 20.0 +3.3 1311
NPL /PTB GPSPPP NPL2 /PT02 1014-2017 / 1001-2016 0.3 2.5 0
NPLI/PTB GPSPPP LI2P /PT02 NC / 1001-2016 0.3 20.0
NRC /PTB GPSPPP NRC4 /PT02 1017-2016 / 1001-2016 0.3 2.5 0
NRL /PTB GPSPPP RL__ /PT02 NC / 1001-2016 0.3 20.0
NTSC/PTB GPSPPP NTP3 /PT02 1001-2016 / 1001-2016 0.3 1.7 0
ONBA/PTB GPS MC ON__ /PT07 1002-2004 / 1001-2016 2.5 11.2 10
ONRJ/PTB GPS P3 RJ01 /PT02 NA_Al / 1001-2016 1.0 7.6 3 +5.6 1302
ORB /PTB GPSPPP OR1Z /PT02 1001-2012 / 1001-2016 0.3 5.4 2
PL /PTB GPSPPP PL_3 /PT02 1101-2013 / 1001-2016 0.3 3.2 2
SASO/PTB GPSPPP SA00 /PT02 NA_Al / 1001-2016 0.3 7.3 2 32.8 1505
SCL /PTB GPS MC SC__ /PT07 1001-1993 / 1001-2016 6.0 14.1 10
SG /PTB GPS P3 SG2P /PT02 1001-2010 / 1001-2016 0.7 5.8 3
SIQ /PTB GPSPPP SI01 /PT02 2002-2014 / 1001-2016 0.3 7.3 2
SMD /PTB GPSPPP SD21 /PT02 2002-2011 / 1001-2016 0.3 7.6 3
SMU /PTB GPS MC SM00 /PT07 NA_Al / 1001-2016 1.5 12.2 10 57.8 0908
SU /PTB GPS MC SU19 /PT07 NA_Al / 1001-2016 1.5 7.1 5 -7.8 1411
TL /PTB GPSPPP TLT1 /PT02 1001-2016 / 1001-2016 0.3 1.8 1
TP /PTB GPSPPP TP04 /PT02 1002-2009 / 1001-2016 0.3 6.4 4
UA /PTB GPS MC UA04 /PT07 2003-2011 / 1001-2016 1.5 8.6 5
UAE /PTB GPS MC AE__ /PT07 2001-2016 / 1001-2016 4.0 8.1 4
UME /PTB GPS P3 UM01 /PT02 1011-2016 / 1001-2016 0.7 2.7 1
VMI /PTB GPS P3 VM__ /PT02 NC / 1001-2016 1.3 20.0
ZA /PTB GPSPPP ZA02 /PT02 1102-2016 / 1001-2016 0.3 4.0 0
Link Type Equipment Cal_ID uStb/ns uCal/ns uAg/ns Al/ns YYMM
AOS /PTB TWSTFT AOS01 /PTB05 0449-2017 0.5 2.7 0
CH /PTB TWGPPP CH01 /PTB01 0284-2012 0.3 1.4 1
IT /PTB TWGPPP IT02 /PTB01 0434-2016 0.3 1.0 0
JATC/NTSC INT LK INTDLY 0.2 10.0 10
NIST/PTB TWSTFT NIST01/PTB01 0393-2015 0.3 5.0 0
OP /PTB TWGPPP OP01 /PTB01 0437-2016 0.3 0.7 0
ROA /PTB TWGPPP ROA01 /PTB01 0440-2016 0.3 0.8 0
SP /PTB TWGPPP SP01 /PTB01 0441-2016 0.3 0.8 0
USNO/PTB TWSTFT USNO01/PTB01 0395-2016 0.3 1.0 0
VSL /PTB TWGPPP VSL01 /PTB01 0295-2015 0.3 1.0 0