| Date: | 2001-03-07 09:20:00 | |
| Sender: | Van Husson, HTSI <Husson, Van <Van.Husson@honeywell-tsi.com>> | |
| Subject: | [SLR-Mail] No. 747: Greenbelt (station 7105) barometric corrections | |
| Author: | Van Husson, HTSI | |
| Content: | ******************************************************************************** SLR Electronic Mail 2001-03-07 09:20:00 UTC Message No. 747 ******************************************************************************** Author: Van Husson, HTSI Subject: Greenbelt (station 7105) barometric corrections Dear colleagues, In the table, below is a set of barometric correction algorithms for MOBLAS-7 at 7105 in Greenbelt, Md. These corrections are the end result of a 7105 Jan 1998 bias investigation prompted by John Ries and Richard Eanes from CSR. The data was recovered by comparing the 7105 pressures from their normal points to the GPS meteorological data from the USNO site in Washington DC. Data from the GODE GPS receiver was also used as a backup to fill in any holes in the USNO GPS data (Thanks to Carey Noll for recovering some 1996 and 1997 GPS met data from back-up). The symptom of this problem was the barometric pressures did not always update (i.e. remained frozen). This was not due to a problem with the barometric unit, but was procedural in nature and was limited to MOBLAS 7 (i.e. never occurred in any other MOBLAS system). You will notice from the table below that the error is random and can vary by +/- 20 millibars (Mb). Bare in mind a barometric error is elevation dependent. A 1 Mb error at 20 and 90 degrees induces a 7 and a 3 mm range bias, respectively (this applies to any SLR satellite). In the table below, a plus barometric error implies the barometric pressure was measuring too high. Likewise, a minus barometric pressure means the pressure was too low. Station 7105 pressures are suspect on Aug 30, 1996 and Oct 28, 1996 and do not appear in the table, because I could not find another independent trustworthy pressure source (e.g. the GODE GPS met data on Aug 30 and 31 1996 pressures did not track the SLR pressures, when the SLR pressures appeared to be valid). We regret any inconvenience this may have caused the users. Any comments or questions about these corrections can be directed to Van Husson at van.husson@honeywell-tsi.com . EPOCH START EPOCH END Pressure Error Uncertainty CDP yy:day:secon yy:day:secon (Millibars) (Millibars) ---- ------------ ------------ -------------- ------------ 7105 97:007:55260 97:007:57500 -0.9 0.7 7105 97:007:63000 97:007:65000 1.2 0.7 7105 97:080:08340 97:080:27000 14.0 0.8 7105 97:080:33540 97:080:37000 13.5 0.8 7105 97:080:41000 97:080:53000 12.8 0.8 7105 97:080:55000 97:080:58000 13.7 0.8 7105 97:080:61000 97:080:63000 15.3 0.8 7105 97:080:68000 97:080:70000 18.3 0.8 7105 97:223:85680 97:224:01000 -0.4 0.4 7105 97:224:03120 97:224:05000 -1.1 0.4 7105 97:224:10500 97:224:18000 -1.4 0.5 7105 97:224:24180 97:224:25000 -0.9 0.4 7105 97:295:49140 97:295:60000 -0.3 0.5 7105 97:295:64020 97:295:72000 0.3 0.5 7105 97:295:76500 97:295:79000 -0.3 0.5 7105 97:295:83400 97:295:86000 -1.1 0.5 7105 97:296:00840 97:296:02000 -1.7 0.5 7105 97:296:06240 97:296:07300 -2.2 0.4 7105 97:296:09240 97:296:33000 -2.7 0.6 7105 97:296:34980 97:296:37000 -3.1 0.5 7105 97:296:38340 97:296:42000 -3.8 0.5 7105 97:296:44340 97:296:59000 -4.3 0.6 7105 97:296:65940 97:297:01000 -1.5 0.6 7105 97:297:02340 97:297:15000 -2.0 0.5 7105 97:297:17280 97:297:35000 -1.5 0.5 7105 97:297:39480 97:297:43000 -2.3 0.5 7105 97:304:23340 97:297:29500 0.4 0.4 7105 97:304:30660 97:304:35000 1.1 0.4 7105 97:304:36780 97:304:40000 0.7 0.4 7105 97:304:74700 97:304:75000 4.2 0.4 7105 97:304:77640 97:304:86300 5.0 0.5 7105 97:306:13740 97:306:15300 22.8 0.4 7105 97:306:17100 97:306:73000 22.2 0.5 7105 97:306:75720 97:306:77000 20.6 0.4 7105 97:306:77640 97:306:80000 19.7 0.5 7105 97:306:81120 97:306:83000 18.5 0.4 7105 97:306:85800 97:307:21000 16.9 0.5 7105 97:307:07260 97:307:08000 15.8 0.4 7105 97:307:10200 97:307:15000 15.2 0.4 7105 97:307:18420 97:307:22000 14.0 0.5 7105 97:307:24960 97:307:31800 13.3 0.5 7105 97:307:31980 97:307:34300 12.7 0.5 7105 97:307:36120 97:307:38000 12.0 0.5 7105 97:307:41100 97:307:42000 11.4 0.4 7105 97:307:47580 97:307:57500 9.9 0.5 7105 97:307:59940 97:307:61000 10.8 0.4 7105 97:307:71820 97:307:72500 11.4 0.4 7105 97:307:75120 97:307:76000 10.6 0.4 7105 97:307:82220 97:307:84000 9.3 0.4 7105 97:308:06300 97:308:09000 -0.9 0.5 7105 97:308:34860 97:308:39300 -0.4 0.4 7105 97:308:41700 97:308:43000 -1.3 0.4 7105 97:308:84840 97:309:01000 -10.2 0.5 7105 97:309:09120 97:309:10000 -12.9 0.4 7105 97:309:11340 97:309:13200 -13.5 0.4 7105 97:309:14040 97:309:16000 -14.2 0.6 7105 97:309:24540 97:309:25100 -0.9 0.4 7105 97:309:27180 97:309:33000 -1.5 0.4 7105 97:309:36060 97:309:37000 -2.1 0.4 7105 97:309:59760 97:309:61000 0.8 0.4 7105 97:309:83400 97:310:12000 1.3 0.5 7105 97:310:13500 97:310:16000 1.6 0.4 7105 97:310:16620 97:310:20000 2.1 0.4 7105 97:310:22140 97:310:23000 2.8 0.4 7105 97:310:25980 97:310:38000 3.7 0.6 7105 97:310:85080 97:311:01000 -1.1 0.4 7105 97:311:06000 97:311:09000 -2.0 0.4 7105 97:311:10080 97:311:16000 -2.6 0.6 7105 97:311:19080 97:311:21000 -3.4 0.5 7105 97:311:32940 97:311:34000 -4.9 0.5 7105 98:020:78720 98:020:81300 -0.9 0.5 7105 98:020:83100 98:020:84000 -1.7 0.5 7105 98:020:85860 98:020:86300 -2.2 0.5 7105 98:021:01080 98:021:02000 -2.7 0.5 7105 98:021:05580 98:021:09500 -3.6 0.6 7105 98:025:45420 98:025:47000 -7.4 0.8 7105 98:025:56580 98:025:61000 -10.4 0.9 7105 98:025:78960 98:025:81500 -11.9 0.8 7105 98:026:07140 98:026:10000 -14.9 0.9 7105 98:026:12180 98:026:13000 -15.7 0.8 7105 98:026:15000 98:026:33000 -16.2 0.9 7105 98:026:34140 98:026:35000 -16.8 0.8 7105 98:026:38820 98:026:42000 -17.3 0.7 7105 98:026:47700 98:026:51000 -18.9 0.7 7105 98:026:56280 98:026:59000 -19.4 0.7 7105 98:027:04320 98:027:30000 -18.9 0.7 7105 98:027:31980 98:027:34000 -18.2 0.8 7105 98:027:34320 98:027:40000 -17.5 0.8 7105 98:027:41940 98:027:46000 -16.9 0.7 7105 98:041:70740 98:041:73300 1.0 0.6 7105 98:041:78240 98:042:02300 0.4 0.7 7105 98:042:15840 98:042:17000 0.6 0.6 7105 98:042:19860 98:042:24000 1.0 0.6 7105 98:042:26340 98:042:28300 1.4 0.6 7105 98:042:29940 98:042:35000 2.0 0.6 7105 98:043:62160 98:043:69300 20.3 0.6 7105 98:043:72060 98:043:73000 19.8 0.5 7105 98:043:74580 98:043:75300 18.7 0.5 7105 98:043:78120 98:043:80000 17.3 0.5 7105 98:043:81120 98:043:84000 16.4 0.7 7105 98:043:84540 98:043:86000 15.5 0.5 7105 98:044:01860 98:044:02500 14.2 0.5 7105 98:044:03420 98:044:04100 13.6 0.5 7105 98:044:07260 98:044:11000 12.5 0.6 7105 98:044:13740 98:044:17000 11.3 0.7 7105 98:044:22500 98:044:24000 10.1 0.7 7105 98:044:26220 98:044:31000 9.4 0.6 7105 98:044:31080 98:044:35000 8.7 0.7 7105 98:044:38580 98:044:40000 8.3 0.6 7105 98:044:57900 98:044:59000 5.9 0.7 7105 98:044:63060 98:044:84000 7.0 0.8 7105 98:045:04080 98:045:05000 6.1 0.6 7105 98:045:76080 98:045:77200 1.0 0.6 7105 98:045:77520 98:045:81000 0.5 0.6 7105 98:045:83820 98:045:84500 -0.5 0.6 7105 98:045:84720 98:046:03000 -1.0 0.7 7105 98:046:10560 98:046:25900 -3.5 0.7 7105 98:046:25980 98:046:27000 -3.9 0.7 7105 98:046:32940 98:046:35500 -5.2 0.7 7105 98:046:37500 98:046:42000 -6.4 0.6 7105 98:046:59040 98:046:61000 -10.2 0.6 7105 98:046:62040 98:046:63000 -9.0 0.6 7105 98:046:68520 98:046:77200 -7.9 0.6 7105 98:046:78300 98:046:83000 -7.2 0.7 7105 98:217:13680 98:217:33840 -0.3 0.5 7105 98:217:37740 98:217:41000 -0.8 0.4 7105 98:217:43500 98:217:58000 -1.5 0.5 7105 98:217:72060 98:217:83000 0.6 0.5 7105 98:321:85500 98:322:01260 -5.5 0.4 7105 98:322:08940 98:322:10000 -7.9 0.4 7105 98:322:55860 98:322:58000 -16.5 0.4 7105 98:322:84180 98:323:12000 -14.8 0.6 7105 98:323:14880 98:323:16000 -14.1 0.4 7105 98:323:22440 98:323:26500 -13.7 0.4 7105 98:323:31320 98:323:34000 -13.4 0.4 7105 98:323:83040 98:323:84000 -6.4 0.4 7105 99:037:78960 99:037:80640 -0.6 0.4 7105 99:037:85500 99:038:00480 -2.2 0.4 7105 99:038:05700 99:038:12000 -3.9 0.4 7105 99:051:48540 99:051:65500 -0.9 0.6 7105 99:058:08220 99:058:14000 -1.5 0.7 7105 99:058:15300 99:058:37000 -2.3 0.8 7105 99:058:40200 99:058:48000 -1.5 0.7 7105 99:058:50820 99:058:58000 -1.0 0.6 7105 99:060:27780 99:060:41000 21.7 0.7 7105 99:060:48300 99:060:57000 20.8 0.7 7105 99:061:01740 99:061:02300 15.1 0.6 7105 99:061:05400 99:061:08500 14.1 0.7 7105 99:061:09600 99:061:16000 13.0 0.8 7105 99:061:21100 99:061:22000 12.1 0.6 7105 99:061:35040 99:061:39000 10.2 0.7 7105 99:061:41340 99:061:42000 9.0 0.6 7105 99:061:45240 99:061:46000 8.2 0.6 7105 99:061:47100 99:061:53000 7.4 0.6 7105 99:061:54000 99:061:62000 6.5 0.8 7105 99:088:38040 99:088:40000 -1.1 0.7 7105 99:138:68400 99:138:70000 3.9 0.6 7105 99:138:73380 99:138:77000 5.6 0.6 7105 99:159:12420 99:159:21000 0.6 0.6 7105 99:159:22020 99:159:37500 1.2 0.7 7105 99:159:44000 99:159:46000 0.9 0.6 7105 99:190:04080 99:190:06000 -0.6 0.6 7105 99:190:07320 99:190:34000 -1.1 0.7 7105 99:190:49380 99:190:51000 -1.1 3.0 7105 99:191:04000 99:191:23000 4.0 0.8 7105 99:191:50580 99:191:51500 2.9 0.6 7105 99:192:50000 99:192:62000 -7.5 0.7 7105 99:192:66000 99:192:68000 -6.5 0.7 7105 99:204:60300 99:204:63000 0.8 0.6 7105 99:204:68460 99:204:70000 1.8 0.6 7105 99:204:76020 99:205:07000 2.8 0.7 7105 99:205:08000 99:205:15000 2.2 0.8 7105 99:205:17000 99:205:22000 2.7 0.7 7105 99:205:27000 99:205:36000 3.5 0.6 7105 99:205:72000 99:205:73500 5.5 0.6 7105 99:205:77000 99:205:78500 7.2 0.6 7105 99:205:80000 99:206:33000 6.2 0.7 7105 99:206:37000 99:206:40000 5.7 0.6 7105 99:206:43000 99:206:61000 4.6 0.7 7105 99:206:64000 99:206:65000 5.7 0.6 7105 99:206:69000 99:206:73000 6.9 0.7 7105 99:206:76000 99:206:86000 7.7 0.6 7105 99:216:02700 99:216:14000 -0.4 0.5 7105 99:216:26000 99:216:51000 0.8 0.6 7105 99:216:73000 99:216:82000 5.8 0.6 7105 99:265:82000 99:265:86000 -0.7 0.7 7105 99:266:02000 99:266:03000 -1.5 0.6 7105 99:266:05000 99:266:11000 -2.2 0.7 7105 99:266:11100 99:266:12000 -2.7 0.6 7105 99:266:13000 99:266:20000 -3.2 0.7 7105 99:266:21120 99:266:24000 -3.7 0.6 7105 99:266:27000 99:266:37000 -4.1 0.6 7105 99:266:39000 99:266:40000 -5.1 0.6 7105 99:266:42000 99:266:53000 -5.7 0.7 7105 99:266:55000 99:266:58000 -6.4 0.6 7105 99:266:70000 99:266:81000 -3.7 0.7 From: ”Husson, Van” ******************************************************************************** |