Technical description of solution usn2001d 2001 November 16 1. Purpose of solution: TRF/CRF for session EOP 2. Analysis center: USN ( United States Naval Observatory ) 3. Short narrative description of solution: Solution usn2001d estimates station position and velocity parameters to define the TRF/CRF for computing EOP time series. Source positions are also estimated. The TRF is attached to ITRF2000 by imposing no-net-rotation and no-net-translation conditions for the positions of a subset of stations and, similarly, no-net-rotation and no-net-translation conditions for the velocities of a subset of stations. The CRF is attached to the ICRF by a no-net-rotation condition using the 212 ICRF defining sources [1]. Parameters are split into three groups: a) global - parameters estimated over all sessions; b) local - parameters estimated for each 24-hour session; c) segmented - parameters estimated over 60 minute time spans. Positions and velocities of all stations were estimated as global parameters. Positions of 527 sources (APPENDIX A) were estimated as global parameters. These 527 sources were considered eligible for estimation as global parameters based on the following criteria: 1) the source had 40 or more good observations; 2) the source was observed during two or more sessions; and 3) the source had N.R.D. less than 1.3 in preliminary solutions. Ninety-two sources with less than 3 total observations and 8 sources with bad data were excluded (APPENDIX B). Positions of the other 143 sources were estimated for each session individually (APPENDIX C). Mean site gradients were computed from a GSFC Data Assimilation Office (DAO) model for met data from 1990-95. Atmospheric gradient delay is modeled as tau = m_grad(el,az) * [GN*cos(az)+GE*sin(az)], where el and az are the elevation and azimuth of the the observation and the gradient mapping function is m_grad. The gradient vector has east and north components GE and GN. Refer to [2], [3]. 4. Estimated parameters: a. celestial frame: right ascension, declination (global and local) b. terrestrial frame: X, Y, Z, Xdot, Ydot, Zdot (global) c. Earth orientation: x, y, UT1-UTC, UT1dot, dpsi, deps (local) d. zenith troposphere: continuous piece-wise linear; 20 min interval; rate constraint generally 50 ps/hr; NMF wet partial derivative (segmented) e. troposphere gradient: 6 hour east and north piece-wise continuous at all stations except a set of 75 stations (APPENDIX D); offset constraint 0.5 mm, rate constraint 2.0 mm/day (segmented) f. station clocks: quadratic + continuous piece-wise linear with 60 min interval; rate constraint generally 5.0E-14 (segmented) g. baseline clocks: set in initial analysis - usually used (local) h. other: global antenna axis offsets for all but 101 stations (APPENDIX E) (global) 5. Celestial reference frame: a. a priori source positions: ICRF b. source positions adjusted in solution: yes If yes, c. definition of orientation: no-net-rotation tie to the ICRF using only ICRF defining sources d. source position estimation: 527 global and 143 local 6. Terrestrial reference frame: a. a priori station positions: ITRF2000 b. a priori station velocities: ITRF2000 c. reference epoch: 1997.0 d. station positions/velocities adjusted in solution: yes If yes, e. definition of origin, orientation, and their time evolution: no-net-translation and no-net-rotation of position for: DSS45 FORTLEZA GILCREEK HARTRAO HOBART26 \ KASHIMA KOKEE LA-VLBA MK-VLBA NRAO20 \ NYALES20 WETTZELL no-net-translation and no-net-rotation of velocity for: DSS45 HOBART26 RICHMOND WESTFORD WETTZELL f. station parameter estimation: X, Y, Z, Xdot, Ydot, Zdot globally for all stations, some with constraints g. stations with constraints: A priori velocity of U, E, and N components for the stations listed in APPENDIX F were constrained to the ITRF2000 velocities with reciprocal weights 0.1, 3.0, and 3.0 mm/yr respectively because the stations have too short history of observations, in many cases only one occupation. The velocities of the 16 pairs of stations listed in APPENDIX G are constrained to be the same. h. stations with discontinuous positions and date of discontinuity: YAKATAGA 871201 SOURDOGH 871201 WHTHORSE 871201 FORTORDS 891001 PRESIDIO 891001 NRAO85 3 901201 MOJAVE12 920627 DSS15 920627 MEDICINA 960601 EFLSBERG 961001 DSS65 970415 TSUKUB32 990401 i. stations with nonlinear velocities: none j. relativity scale: Formula 29 in IERS Conventions 1992, page 127-136 was used. k. permanent tide correction: yes "Yes" means that both the permanent and the periodic tides have been modeled, so that the output station position is for after the removal of both the permanent and the periodic tidal effect. 7. Earth orientation: a. a priori precession model: IERS 1996 b. a priori nutation model: IERS 1996 c. a priori short-period tidal variations in x, y, UT1 were taken into account in accordance with the model presented in APPENDIX H. d. EOP estimation: x, y, UT1, UT1dot, deps, dpsi each day with a priori error of 45 mas for pole and 3 ms for UT1 to allow estimation for one-baseline sessions, although most (all?) one-baseline sessions are removed from the session list before the solution is run; deps and dpsi are relative to IAU 1976 precession and IAU 1980 nutation models. The time tag of the EOP series is the middle epoch of each observing session. The final series of polar motion and UT1 do not contain contributions due to the high frequency variations. The model specified in APPENDIX H was added to the a priori EOP and was not subtracted from the estimates. 8. A priori geophysical models: a. troposphere: NMF dry mapping function; Saastamoinen zenith delay calculated using logged pressure, temperature; a priori mean gradients from VLBI data or DAO weather model. b. solid Earth tide: IERS Conventions 1996, p.56-65, step 1 and step 2, anelasticity variant, including tides of the 3-rd order. c. ocean loading: IERS Conventions 1996, 11 tidal waves in accordance with Schwiderski model, no nodal correction, no interpolation within the band. d. atmosphere loading: VLBI estimates from VLBI [4] were used for the most frequently observed sites: GILCREEK HATCREEK HAYSTACK HRAS 085 (FD-VLBA,MCD 7850,FTD 7900) MOJAVE12 (MOJ 7288, DSS15) ONSALA60 (MV2ONSLA) RICHMOND (MIAMI20) WESTFORD (HAYSTACK) WETTZELL For the remaining stations we used values derived theoretically by convolution of a loading Green's function with meteorological surface pressure data. These values are from T. vanDam (personal communication) for all other sites except KASHIMA KASHIM34 KAUAI for which values from S. Manabe [5] were used. The estimate of station positions are related to the reference pressure at the station (APPENDIX I). 9. Data type: group delays 10. Data editing: 7 degree elevation cutoff 11. Data weighting. Weights are defined as follows: 1/sqrt ( f**2 + a**2 ) where "f" is the formal uncertainty of the ionosphere free linear combination of group delays at X- and S-band obtained by fringe fitting on the base of achieved signal to noise ratio. Station-dependent parameter "a" was computed for each session by an iterative procedure such that the ratio of the sum of squares of the weighted residuals to the estimate of their mathematical expectation is about unity. 12. Standard errors reported: All errors are derived from least-squares estimation propagated from the data weights and the constraints applied to the troposphere, clock and EOP parameters. 13. Software: Calc 9.1x, SOLVE release: 2001.06.05; SOLVE revision: 2001.09.20 14. Other information: Mean pole coordinates used for computation of pole tide deformation were set to 0. References: 1. COORDINATES OF THE DEFINING SOURCES IN ICRF http://hpiers.obspm.fr/webiers/results/icrf/icrfdef.html 2. MacMillan, D.S. and C. Ma, Atmospheric gradients from very long baseline interferometry observations, Geophys. Res. Lett., 22, 1041-1044, 1995. 3. MacMillan, D.S. and C. Ma, Atmospheric gradients and the VLBI terrestrial and celestial reference frames, Geophys. Res. Lett., 24, 453-456, 1997. 4. MacMillan, D.S. and J.M. Gipson, Atmospheric pressure loading parameters from very long baseline interferometry observations, J. Geophys. Res., 99, 18081-18087, 1994. 5. Manabe, S., T. Sato, S. Sakai, and K. Yokoyama, Atmospheric loading effect on VLBI observations, in Proceedings of the AGU Chapman Conference on Geodetic VLBI: Monitoring Global Change, NOAA Tech. Rep. NOS 137 NGS 49, 111-122, 1991. APPENDIX A. ----------- Sources whose positions were estimated as global parameters. 0003+380 0003-066 IIIZW2 0007+171 0008-264 0010+405 0013-005 0014+813 \ 0016+731 0019+058 0026+346 0035+413 0039+230 NGC0262 0047-579 0048-097 \ NGC0315 0056-001 0059+581 0104-408 0106+013 0109+224 0110+495 0111+021 \ 0112-017 0113-118 0118-272 0119+115 0119+041 0123+257 0130-171 0133+476 \ 0135-247 0138-097 0146+056 0148+274 0149+218 0151+474 0153+744 0159+723 \ 0201+113 0202+149 0202-172 0202+319 0208-512 0212+735 0215+015 0219+428 \ 0220-349 0221+067 4C67.05 0229+131 0234+285 0235+164 0237-027 0237+040 \ LSI61303 NGC1052 0239+108 0241+622 0256+075 0259+121 0300+470 0302-623 \ 0302+625 NGC1218 0306+102 0308-611 0309+411 3C84 0317+188 0319+121 \ 0322+222 0326+278 0332-403 NRAO140 CTA26 0338-214 0341+158 0342+147 \ NRAO150 0400-319 0400+258 0402-362 0403-132 0405-385 0405-123 0405+305 \ 0406-127 0406+121 0409+229 0414-189 0420-014 0420+417 0422-380 0422+004 \ 0423+051 0425+048 0426-380 0426+273 0430+289 0434-188 0437-454 0438-436 \ NRAO190 0440+345 0446+112 0444+634 0454-810 0451-282 0454-234 0457+024 \ 0458-020 0458+138 0459+060 0500+019 0502+049 0454+844 0506+101 0507+179 \ 0511-220 0516-621 3C138 0521-365 0524-460 0530-727 0528-250 0528+134 \ 0529+075 0537-441 0537-158 0536+145 0537-286 0539-057 3C147 0544+273 \ 0552+398 0554+242 0556+238 0600+177 0602+405 0602+673 0605-085 0607-157 \ 0610+260 0611+131 0609+607 0620+389 0615+820 0637-752 0636+680 3C166 \ 0642+449 0646-306 0648-165 0650+371 0651+410 0657+172 0707+476 0711+356 \ 0716+714 0722+145 0723-008 0718+793 0727-115 0733-174 0735+178 0738-674 \ 0736+017 0738+313 0738+491 0742+103 0743-006 0743+259 0745+241 0748+126 \ 0749+540 0754+100 0805+046 0805-077 0804+499 0805+410 0808+019 0812+367 \ 0814+425 0818-128 0820+560 0821+621 0823+033 0826-373 0827+243 0829+046 \ 0828+493 0831+557 0834-201 0833+585 0836+710 0839+187 0850+581 OJ287 \ 0859-140 0859+470 0906+015 0912+029 0912+297 0917+449 0919-260 0917+624 \ 0920-397 0920+390 4C39.25 0925-203 0945+408 0949+354 0952+179 SN1993J \ M81 OK290 0955+476 0955+326 0954+658 1004+141 1011+250 1012+232 \ 1014+615 1020+400 1021-006 1022+194 1030+415 1030+074 1032-199 1034-293 \ 1038+064 1038+52A 1038+52B 3C245 1039+811 1042+071 1045-188 1044+719 \ 1048-313 1049+215 1053+704 1053+815 1055+018 1057-797 1101-536 1101+384 \ 1104-445 1104+728 1111+149 1116+128 1123+264 1124-186 1125+596 1127-145 \ 1128+385 1128-047 1130+009 MRK180 NGC3862 1143-245 1144+402 1144-379 \ 1145-071 NGC3894 1147+245 1148-001 1150+812 1150+497 1155+251 1156-094 \ 1156+295 1213-172 1213+350 1215+303 1216+487 1219+285 1219+044 1221+809 \ 1222+037 M84 1226-028 1226+373 3C273B 3C274 1236+077 1237-101 \ 1239+376 1240+381 1243-072 1244-255 1252+119 1251-713 3C279 1254+571 \ 1255-316 1257+145 1300+580 1302-102 1307+121 1308+326 1308+328 1313-333 \ OP326 1324+224 3C286 1330+476 1334-127 1338+381 1342+662 1342+663 \ 1347+539 1351-018 1352-104 1354+195 1354-174 1354-152 1357+769 1402-012 \ 1402+044 OQ208 1406-076 1409+218 1413+135 1413+349 1416+067 1418+546 \ 1417+385 1417+273 1420+326 1424+366 1424+240 1424-418 1427+543 1428+422 \ NGC5675 1430-178 1432+200 1433+304 1435+638 1435-218 OQ172 1443-162 \ 1445-161 1448+762 1451-375 1451-400 1459+480 1502+106 1502+036 1504+377 \ 1504-166 1508+572 1508-055 1510-089 1511-100 1514+197 1514-241 1519-273 \ 1532+016 1538+149 1547+507 1546+027 1548+056 1549-790 1555+001 1555-140 \ 1557+032 1600+335 1604-333 1606+106 CTD93 1611+343 1614+051 1610-771 \ 1616+063 1619-680 1622-253 1624+416 1622-297 NGC6251 1633+38 1636+473 \ 1637+574 NRAO512 1639+230 1642+690 3C345 DA426 1656+348 1656+477 \ 1655+077 1656+053 1657-261 1705+456 1705+018 1706-174 1717+178 1726+455 \ 1727+502 1725+044 NRAO530 1732+389 1734+363 1734+508 1738+499 1738+476 \ 1739+522 1741-038 NGC6454 1743+173 1745+624 1746+470 1749+701 1749+096 \ 1751+441 1751+288 1758+388 1803+784 1800+440 3C371 1806+456 1815-553 \ 1817-254 1821+107 1823+568 1830+285 1831-711 3C390.3 1842+681 1849+670 \ 1856+736 3C395 1908-201 1920-211 1921-293 1923+210 1928+738 1926+087 \ 1929+226 1932+204 1933-400 1936-155 1937-101 1943+228 1951+355 1954+513 \ 1955+335 1954-388 1958-179 2000+472 2000-330 2007+777 2005+642 2005+403 \ OW-015 2008-159 2017+743 2021+317 2023+336 2030+547 2029+121 3C418 \ 2037-253 CL4 2051+745 2052-474 2054-377 2059+034 2106-413 2113+293 \ 2109-811 2121+053 2126-158 2128+048 2128-123 2131-021 2134+00 2136+141 \ 2143-156 2144+092 2145+067 2149+056 2149-306 2150+173 2155-152 2155-304 \ VR422201 2201+315 2209+236 2210-257 2214+350 2216-038 3C446 2227-088 \ 2229+695 CTA102 2232-488 2234+282 2233-148 2235+731 2243-123 2245-328 \ 2250+194 3C454.3 2252-089 2253+417 2254+074 2254+024 2255-282 2318+049 \ 2319+272 2320+506 2320-035 2325-150 2328+107 2329-162 2331-240 2335-027 \ 2344+09A 2345-167 2351+456 2351-154 2355-534 2355-106 2356+385 APPENDIX B. ----------- Sources whose data was not used. Sources with less than three total observations. UG00192 4C+00.02 OB338 0036-216 NGC0253 M77 0252-712 NGC1167 \ UXARI 0335-122 0336-017 0340+044 0420-625 0428+205 0431-512 0454-463 \ HD32918 0512+249 0522-611 0534-611 0537-692 NGC2110 0558-504 MRK003 \ 0614-349 NGC2146 0622-441 0647-475 0700-465 0727-365 0743-673 0809-493 \ VELA 0842-754 0844+387 0902+343 0941-080 M82 NGC3079 1015-314 \ 1017+109 1020-103 1039-474 NGC3690 1129-580 1206-399 M106 NGC4261 \ 1221-829 1225-023 1239-044 1245-197 1305-241 NGC5077 1328+254 1329-665 \ 1355-416 1422+268 1439+327 HD132742 1511+238 1600-445 SIGCRB 1622+238 \ 3C343 3C343.1 NGC6240 1713+218 1729-373 1742-283 1756-663 1813-241 \ 1827-360 1829-106 1855+031 1903-802 NAQL93 1920+154 1934+207 1936-623 \ 1955+343 CYGNUS-A 2027+383 NGC6946 2044-168 2142-758 2209+184 2259-375 \ 2300-307 2300-683 2310-417 2322-411 Sources with bad data. 0218+357 0218+35A 0218+35B 1031+567 1830-211 1830-21A 1830-21B 1947+079 \ APPENDIX C. ----------- Sources whose positions were estimated as arc parameters. 0002-478 0008-421 0022-423 0056-572 0108+388 0116+319 0119+247 0127+084 0131-522 0147-076 0150-334 0153-410 0201+088 0202-765 0230-790 0237-233 0248+430 0252-549 0307+380 0312-770 0331+022 0334+014 0334-546 0335-364 0355-483 0407-658 0415+379 0423+233 0450-743 0503-608 0506-612 0517-726 0600+219 0615-365 0629-418 0637-337 0656+082 0710+439 0736-332 0821+394 0822+137 0823-223 0823-500 0834+250 0836+182 0854+213 0936-853 0937+262 0942+358 0952+581 0959-443 1004-500 1026-084 1043+066 1101-325 1105-680 1116-462 1117+146 1144+352 1148-671 1217+023 1234-504 1236-684 1239+606 1251-407 1320-446 1323+321 1327+321 1334-649 1345+125 1349-439 1352-632 1436+373 1437+331 1444+175 1451+270 1600+43A 1600+43B 1628+216 1647-296 1718-649 1733-565 1740-517 1748-253 1758-651 1806-458 1814-637 1815+531 1822-173 1826+796 1829-718 1843+400 1848+283 1852-534 1910+052 1919+086 1922+155 1925-610 1932+106 1934-638 1935-692 1950-613 2005-489 2021+614 2058-425 2059-786 2100+468 2106+143 2120+099 2142+110 2145+082 2146-783 2147+077 2152-699 2201+171 2204-540 2211-388 2227-399 2229-172 2309+454 2311-452 2312-319 2326-477 2329-384 2333-528 2337+264 2352+495 2353-686 3C120 3C309.1 3C48 4C55.17 CEN-A HR1099 M104 NGC2484 NGC4278 NGC6034 NGC6500 UG01841 UG03927 UGC02748 VELA-G APPENDIX D. ----------- List of 75 stations for which troposphere gradients were not estimated. AIRA AUSTINTX AZORES BERMUDA BLKBUTTE \ BLOOMIND BREST CARNUSTY CARROLGA CHICHI10 \ DEADMANL ELY FLAGSTAF FORT_ORD FORTORDS \ FTD_7900 GIFU3 GOLDMARS GORF7102 GGAO7108 \ GRASSE HALEAKAL HOFN HOHENFRG HOHNBERG \ JPL_MV1 KARLBURG KASHIM11 KIRSBERG KODIAK \ KOGANEI LEONRDOK MAMMOTHL MCD_7850 METSHOVI \ MILESMON MADRID64 MIURA MIYAZAKI MIZUSGSI \ MOJ_7288 MV2ONSLA MON_PEAK NOME OCOTILLO \ OVR_7853 PBLOSSOM PENTICTN PINFLATS PLATTVIL \ PRESIDIO PT_REYES PVERDES QUINCY SAGARA \ SANPAULA SEATTLE1 SINTOTU SINTOTU3 SNDPOINT \ SOURDOGH SUWON TATEYAMA TITIJIMA TOULOUSE \ TROMSONO TRYSILNO TSUKUBA USUDA64 VERNAL \ VICTORIA WHTHORSE YAKATAGA YELLOWKN YUMA APPENDIX E. ----------- List of 101 stations for which axis offsets were not estimated. AIRA AUSTINTX AZORES BERMUDA BLKBUTTE \ BLOOMIND BREST CARNUSTY CARROLGA CHICHI10 \ CHLBOLTN CRIMEA DAITO DEADMANL DSS15 \ ELY FLAGSTAF FORTORDS FORT_ORD FTD_7900 \ GGAO7108 GIFU3 GOLDVENU GORF7102 GRASSE \ HALEAKAL HOFN HOHENFRG HOHNBERG JPL_MV1 \ KARLBURG KASHIM11 KIRSBERG KODIAK KOGANEI \ KWAJAL26 LEONRDOK MAMMOTHL MARCUS MARPOINT \ MCD_7850 METSHOVI MIAMI20 MILESMON MIURA \ MIYAZAKI MIZNAO10 MIZUSGSI MIZUSGSI MOJ_7288 \ MON_PEAK MV2ONSLA NOBEY_6M NOME NRAO85_1 \ OCOTILLO OHIGGINS OVR_7853 PARKES PBLOSSOM \ PENTICTN PINFLATS PLATTVIL PRESIDIO PT_REYES \ PVERDES QUINCY ROBLED32 SAGARA SANPAULA \ SEATTLE1 SESHAN25 SEST SHANGHAI SINTOTU \ SINTOTU3 SNDPOINT SOURDOGH SUWON SYOWA \ TATEYAMA TITIJIMA TOULOUSE TROMSONO TRYSILNO \ TSUKUB32 TIDBIN64 TIGOWTZL TSUKUBA URUMQI \ USSURISK USUDA64 VERNAL VICTORIA VLA \ WHTHORSE YAKATAGA YEBES YELLOWKN YLOW7296 \ YUMA APPENDIX F. ----------- List of 37 stations with constraints on velocity. AUSTINTX AZORES BERMUDA BLOOMIND BREST \ CARNUSTY CARROLGA CHLBOLTN DAITO FTD_7900 \ GIFU3 GRASSE HOFN HOHENFRG HOHNBERG \ KARLBURG KIRSBERG LEONRDOK MCD_7850 METSHOVI \ MILESMON MIYAZAKI MIZNAO10 MIZUSGSI NOBEY_6M \ OCOTILLO SAGARA SEST SUWON SYOWA \ TIDBIN64 TITIJIMA TOULOUSE USSURISK USUDA64 \ VICTORIA VLA APPENDIX G. ----------- Velocities of these pairs of stations were constrained to be the same. DSS15 GOLDMARS \ DSS45 TIDBIN64 \ DSS65 ROBLED32 \ DSS65 MADRID64 \ FORT_ORD FORTORDS \ GORF7102 GGAO7108 \ KAUAI HALEAKAL \ MOJAVE12 MOJ_7288 \ NRAO_140 NRAO85_1 \ ONSALA60 MV2ONSLA \ OVRO_130 OVR_7853 \ RICHMOND MIAMI20 \ SESHAN25 SHANGHAI \ SINTOTU SINTOTU3 \ WETTZELL TIGOWTZL \ YELLOWKN YLOW7296 APPENDIX H. ----------- Expansion of short-period variations in polar motion and UT1. UT1 tidal terms (microseconds) l l' F D Om GST | Cos | Sin | +pi | | | ----------------------------------------- 2 0 2 0 2 -1 -0.42 -0.86 0 0 2 2 2 -1 -0.05 -0.37 1 0 2 0 1 -1 -0.49 -0.99 1 0 2 0 2 -1 -2.57 -5.27 -1 0 2 2 2 -1 -0.69 -1.08 0 0 2 0 1 -1 -2.58 -3.37 0 0 2 0 2 -1 -13.70 -17.89 -1 0 2 0 2 -1 0.76 0.19 1 0 0 0 0 -1 0.87 0.61 0 1 2 -2 2 -1 -0.10 -0.23 0 0 2 -2 2 -1 -2.76 -5.26 0 1 0 0 0 -1 1.06 2.14 0 0 0 0 -1 -1 -0.18 -0.32 0 0 0 0 0 -1 9.20 16.05 0 0 0 0 1 -1 1.25 2.18 0 -1 0 0 0 -1 -0.42 0.06 0 0 -2 2 -2 -1 0.14 -0.06 -1 0 0 0 0 -1 -0.10 1.18 0 0 -2 0 -2 -1 1.02 0.37 0 0 -2 0 -1 -1 0.65 0.24 -1 0 -2 0 -2 -1 0.14 0.48 -1 0 -2 0 -1 -1 0.09 0.31 2 0 2 0 2 -2 -0.37 0.87 0 0 2 2 2 -2 -0.70 0.42 1 0 2 0 2 -2 -2.05 3.28 -1 0 2 2 2 -2 0.00 0.69 0 0 2 0 1 -2 0.38 -0.57 0 0 2 0 2 -2 -10.05 15.27 -1 0 2 0 2 -2 -0.10 -0.15 0 1 2 -2 2 -2 -0.07 0.05 0 0 2 -2 2 -2 -0.85 7.81 0 1 0 0 0 -2 0.29 0.07 0 0 0 0 0 -2 0.56 2.55 0 0 0 0 1 -2 0.17 0.76 0 0 3 0 3 -3 0.29 -0.07 Polar motion tidal terms (microarcseconds) l l' F D Om GST | Cos | Sin | +pi | | | ----------------------------------------- -2 0 -2 0 -2 1 -9.61 10.46 0 0 -2 -2 -2 1 -2.10 6.59 -1 0 -2 0 -1 1 -5.69 1.36 -1 0 -2 0 -2 1 -30.17 7.22 1 0 -2 -2 -2 1 -6.11 3.75 0 0 -2 0 -1 1 -25.99 8.52 0 0 -2 0 -2 1 -137.83 45.19 1 0 -2 0 -2 1 0.02 4.31 -1 0 0 0 0 1 -2.08 -2.41 0 -1 -2 2 -2 1 -0.83 -0.64 0 0 -2 2 -2 1 -43.93 18.22 0 -1 0 0 0 1 28.38 6.45 0 0 0 0 1 1 -3.04 1.59 0 0 0 0 0 1 153.82 -80.29 0 0 0 0 -1 1 20.86 -10.89 0 1 0 0 0 1 1.94 -2.77 0 0 2 -2 2 1 1.27 9.68 1 0 0 0 0 1 3.54 -5.74 0 0 2 0 2 1 5.56 -8.97 0 0 2 0 1 1 3.56 -5.74 1 0 2 0 2 1 2.27 4.21 1 0 2 0 1 1 1.45 2.69 -2 0 -2 0 -2 2 -0.03 -0.18 0 0 -2 -2 -2 2 2.91 -4.06 -1 0 -2 0 -2 2 6.79 -11.88 1 0 -2 -2 -2 2 5.56 1.78 0 0 -2 0 -1 2 -1.04 2.26 0 0 -2 0 -2 2 27.76 -60.45 1 0 -2 0 -2 2 -0.84 -0.96 0 -1 -2 2 -2 2 4.79 -4.67 0 0 -2 2 -2 2 0.92 -19.76 0 -1 0 0 0 2 0.04 0.13 0 0 0 0 0 2 -0.24 -15.36 0 0 0 0 -1 2 -0.07 -4.58 0 0 -3 0 -3 3 -0.31 -4.83 2 0 2 0 2 -2 -0.92 8.15 0 0 2 2 2 -2 -0.30 10.73 1 0 2 0 2 -2 1.30 41.48 -1 0 2 2 2 -2 -8.46 15.22 0 0 2 0 1 -2 0.40 -9.74 0 0 2 0 2 -2 -10.77 261.15 -1 0 2 0 2 -2 0.59 -7.09 0 1 2 -2 2 -2 -8.99 0.66 0 0 2 -2 2 -2 -70.34 109.31 0 1 0 0 0 -2 -1.94 -3.02 0 0 0 0 0 -2 -18.82 8.37 0 0 0 0 1 -2 -5.61 2.49 0 0 3 0 3 -3 0.77 -3.13 APPENDIX I. ----------- Reference station pressure (in mbar). ALGOPARK -.4200 987.7269 AUSTINTX -.4500 987.8843 AZORES .0000 980.0000 BERMUDA -.1700 1032.0591 BLKBUTTE -.4600 958.2020 BLOOMIND -.3900 986.2808 BR-VLBA -.4700 991.1151 BREST -.3500 1018.2115 CARNUSTY -.2700 1006.7997 CARROLGA -.4600 983.5973 CHLBOLTN -.2400 1004.2083 CRIMEA -.3700 1022.2811 DAITO -.1700 1004.8062 DEADMANL -.3900 921.1954 DSS15 -.2980 903.3864 DSS45 -.3600 940.8996 DSS65 -.3700 927.3283 EFLSBERG -.4400 973.3153 ELY -.4600 818.4020 FD-VLBA -.4363 840.9660 FLAGSTAF -.5400 780.6606 FORT ORD -.3000 1026.5164 FORTLEZA -.4600 1008.8414 FORTORDS -.3000 996.2424 FTD 7900 -.4363 843.6926 GGAO7108 -.3600 1009.1006 GILCREEK -.3470 973.5949 GOLDVENU -.4200 907.6266 GORF7102 -.3600 1013.7940 GRASSE -.2800 880.8029 HALEAKAL .0000 980.0000 HARTRAO -.5100 872.2941 HATCREEK -.3257 903.4485 HAYSTACK -.4330 1004.2732 HN-VLBA -.3600 974.3740 HOBART26 -.0680 1015.8087 HOFN -.4000 1008.1025 HOHENFRG -.3900 1006.0411 HOHNBERG -.4000 914.8175 HRAS 085 -.4363 841.6975 JPL MV1 -.3600 968.8810 KARLBURG -.4000 1024.5398 KASHIM34 -.1670 1011.8796 KASHIMA -.1670 1011.6565 KAUAI -.0500 893.1727 KIRSBERG -.4000 999.8500 KODIAK -.3700 1019.8853 KOKEE -.0530 897.6151 KP-VLBA -.5100 809.7043 KWAJAL26 -.0310 1010.4768 LA-VLBA -.4800 805.6143 LEONRDOK -.4900 987.2458 MAMMOTHL -.4200 788.4177 MARCUS .0000 980.0000 MARPOINT -.3500 1015.3604 MATERA -.3400 957.6935 MCD 7850 -.4363 804.4337 MEDICINA -.4100 1015.4830 METSHOVI -.4100 1007.9857 MIAMI20 -.1960 1015.2756 MILESMON -.4700 929.2285 MIYAZAKI -.1670 1010.7844 MIZNAO10 -.1700 1005.5121 MIZUSGSI -.1700 1001.3473 MK-VLBA .0000 980.0000 MOJ 7288 -.2978 904.4807 MOJAVE12 -.2978 910.8149 MON PEAK -.4300 817.6861 MV2ONSLA -.1590 1018.9158 NL-VLBA -.4100 992.0599 NOBEY 6M -.2500 888.1540 NOME -.3200 979.4225 NOTO -.3600 1004.8668 NRAO 140 -.4100 924.2388 NRAO20 -.4100 921.1600 NRAO85 1 -.4100 925.3710 NRAO85 3 -.4100 925.6830 NYALES20 -.2100 999.8049 OCOTILLO -.4300 1018.0067 OHIGGINS -.2300 995.1413 ONSALA60 -.1590 1008.6664 OV-VLBA -.3600 884.1696 OVR 7853 -.3600 888.0806 OVRO 130 -.3600 885.8806 PARKES -.4000 967.9925 PBLOSSOM -.3800 913.4080 PENTICTN -.4400 966.3524 PIETOWN -.4400 766.7355 PINFLATS -.4400 888.9036 PLATTVIL -.4600 854.2665 PRESIDIO -.3200 1025.0298 PT REYES -.3200 1027.5281 PVERDES -.3200 1020.2778 QUINCY -.3600 897.4122 RICHMOND -.1960 1017.6532 ROBLED32 -.3700 1007.4550 SAGARA -.4000 1002.6400 SANPAULA -.3900 1010.2264 SANTIA12 -.3300 937.0019 SC-VLBA -.0500 994.8800 SEATTLE1 -.4000 1043.2625 SESHAN25 -.3200 1013.3407 SEST -.3100 774.8864 SHANGHAI -.3790 1012.1340 SINTOTU -.1670 1003.8890 SNDPOINT -.3700 1011.2705 SOURDOGH -.4300 952.7302 TIDBIN64 -.3600 937.1552 TITIJIMA -.1670 1012.7039 TOULOUSE -.4000 1013.0025 TROMSONO -.3100 1001.7485 TRYSILNO -.3700 932.2366 TSUKUBA -.1670 1011.0706 URUMQI -.5900 798.9826 USSURISK -.3800 993.4937 USUDA64 -.2600 847.8439 VERNAL -.4900 851.8669 VICTORIA -.3700 1025.1324 VLA -.4400 788.5615 VNDNBERG -.3200 1008.3600 WESTFORD -.4330 1005.9516 WETTZELL -.5290 946.1236 WHTHORSE -.4300 931.0909 YAKATAGA -.3700 1018.9455 YEBES -.4200 907.5895 YELLOWKN -.4400 986.8436 YLOW7296 -.4400 987.1935 YUMA -.4500 979.1090 VLBA85 3 -.4000 980.0000 WIDE85 3 -.4100 924.0000 BADARI -.5500 945.6600 BEARLAKE -.4800 989.6000 HYDERBAD -.5200 967.1800 KAGOSHMA -.2200 1010.3000 KIRUNA -.3700 991.8800 KYUSHU -.1670 1007.1000 MCMURDO -.3600 968.2900 SVETLOE -.4100 996.6600 SYOWA -.4900 921.6600 TAHITI .0000 980.0000 TORUN -.4400 986.1500 ULANUDE -.5700 900.1300 WESTBRK0 -.4000 996.3600 YEVPATOR -.4600 967.7200 ZELENCHK -.5100 967.4900 DEFAULT .0000 980.0000