NCGS

Geodetic News Archive


FAA issues notice of GPS interference testing
Friday, January 22, 2021

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
CARRIER STRIKE GROUP FOUR (CSG4) 21-01
17 – 27 January 2021 / Carrier Strike Group Four

This test will be centered at 30.937500°, -79.687500°, which is 101 NM ENE of the Craig (CRG) VORTAC in Jacksonville, Florida, and extend outward and upward like a bowl affecting the GPS signal 148 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (0 ft MSL), 217 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 1200 Z - 2230 Z (7:00 pm EST – 5:30 pm EST) January 17th and January 24th - 27th with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 170 NM. Since this radius is relative to the CP’s ground elevation (0 ft MSL), the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 540 ft, 10 NM for 720 ft, 15 NM for 940 ft, and 20 NM for 1,200 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.


FAA issues notice of GPS interference testing
Monday, November 9, 2020

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
MARINE SPECIAL OPERATIONS COMMAND (MARSOC) 20-05
08 – 16 November 2020 / Ivanhoe, NC

This test will be centered at 34.648611°, -78.298333° and extend outward and upward like a bowl affecting the GPS signal 69 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (~80 ft mean sea level or MSL), 123 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 0000 Z - 0600 Z (7:00 pm EST – 1:00 am EST) November 8-16 with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 90 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 600 ft, 10 NM for 880 ft, 15 NM for 1,270 ft, and 20 NM for 1,800 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.


FAA issues notice of GPS interference testing
Monday, October 12, 2020

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
FORT BRAGG NORTH CAROLINA (FTBRNC) 20-29
11 – 16 October 2020 / Ft. Bragg, NC

This test will be centered at 35.139444°, -79.163333° and extend outward and upward like a narrow test tube affecting the GPS signal 27 Nautical miles (NM) away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~300 ft mean sea level or MSL) plus the height of the broadcasting antenna, 30 NM away at 4,000 ft AGL, 30 NM away at 10,000 ft MSL, and so on. These tests will be conducted daily 0601 Z - 2359 Z (2:01 am EDT - 7:59 pm EDT) with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 28 NM. Due to the steepness of this curve, NCGS recommends adding a 5 NM buffer for any low altitude UAV ops and a 10 NM buffer for any UAV ops near 400 ft AGL.

Please note that the testing centered at Fort Bragg will be encompassed by the testing near Ivanhoe, NC, but the testing near Ivanhoe will be conducted at night [0000 Z - 0600 Z (8:00 pm EDT – 2:00 am EDT)].


FAA issues notice of GPS interference testing
Monday, October 12, 2020

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
MARINE SPECIAL OPERATIONS COMMAND (MARSOC) 20-04
11 October – 02 November 2020 / Ivanhoe, NC

This test will be centered at 34.648611°, -78.298333° and extend outward and upward like a bowl affecting the GPS signal 69 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elev (~80 ft mean sea level or MSL), 123 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 0000 Z - 0600 Z (8:00 pm EDT – 2:00 am EDT) Oct 11 – 15 and Oct 27 – Nov 2 with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 90 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 600 ft, 10 NM for 880 ft, 15 NM for 1,270 ft, and 20 NM for 1,800 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

Please note that the testing centered near Ivanhoe will encompass the testing at Fort Bragg, but the testing near Fort Bragg will be conducted later in the day [0601 Z - 2359 Z (2:01 am EDT - 7:59 pm EDT)].


FAA issues notice of GPS interference testing
Wednesday, August 5, 2020

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
NAVY WARFARE DEVELOPMENT CENTER (NWDC) 20-01 (Revision 1)
07 – 10 August 2020 / Portsmouth, VA

This test will be centered at 36.950000°, -76.308333° and extend outward and upward like a bowl affecting the GPS signal 49 nautical miles (NM) away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~7 ft MSL) plus the height of the antenna, 107 NM away at 4,000 ft AGL, and so on. The tests will be conducted daily 2130 Z - 2300 Z (5:30 PM - 7:00 PM EDT).

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 60 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 601 ft, 10 NM for 844 ft, 15 NM for 1,129 ft, and 20 NM for 1,456 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.


Intermittent issues with NCGS Geodetic Control Database
Friday, August 21, 2020

Users of the NCGS Geodetic Control Database (https://ncgs.nc.gov/geodeticmonuments) may notice some intermittent outages. NCGS is aware of the issue and is working to resolve it as quickly as possible.

In the meantime, users may want to try accessing the database via a different browser, and/or users may try a hard refresh to force the browser to fully reload the database page. On most browsers a hard refresh can be accomlished by pressing CTRL+F5, but users should consult their browser help resources for exact instructions. Neither of these solutions are a guaranteed fix, but they have resolved the issue in some cases.


FAA issues notice of GPS interference testing
Monday, March 23, 2020

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
FORT BRAGG NORTH CAROLINA (FTBRNC) 20-27
23 – 27 March 2020 / Ft. Bragg, NC

This test will be centered at 35.157222°, -79.293333° and extend outward and upward like a bowl affecting the GPS signal 26 NM away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~465 ft MSL), 85 NM away at 4,000 ft AGL, and so on.

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 46 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 584 ft, 10 NM for 823 ft, 15 NM for 1,127 ft, and 20 NM for 1,506 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.


FAA issues notice of GPS interference testing
Tuesday, March 03, 2020
 
The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:
 

This test will be centered at 34.373056°, -77.178333°, which is located 13.3 nautical miles (NM) southeast of the Sandview Pier, and extend outward and upward like a bowl affecting the GPS signal 23 NM away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~0 ft MSL), 75 NM away at 4,000 ft AGL, and so on.

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 41 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 598 ft, 10 NM for 859 ft, 15 NM for 1,192 ft, and 20 NM for 1,607 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.
 

FAA issues notice of GPS interference testing
Monday, February 17, 2020
 
The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:
 

This test will be centered at 34.902222°, -76.885556° and extend outward and upward like a bowl affecting the GPS signal 61 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elev (~24 ft MSL), 121 NM away at 4,000 ft AGL, and so on.

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 73 NM. Since this radius is relative to the CP’s ground elev, the radius needs to be extended by 5 NM for UAV ops at higher ground elevations where the combined ground elev difference (remote site elev – CP elev) + UAV flight elev approaches or exceeds 636 ft, 10 NM for 904 ft, 15 NM for 1,206 ft, and 20 NM for 1,542 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for ops near 400 ft AGL.
 

FAA issues notice of GPS interference testing
Tuesday, February 11, 2020
 
The Federal Aviation Administration (FAA) has issued a notice of GPS interference testing in the vicinity of Fort Bragg, NC that​ may affect GPS signal for surveyors and unmanned aircraft operators. For details and a map showing the affected area, please see the advisory below.
 
FLIGHT ADVISORY - GPS Interference Testing
FORT BRAGG NORTH CAROLINA (FTBRNC) 20-14
11 - 13 February 2020
Fort Bragg, NC

Additional information is available at the link below:

For unmanned aircraft operators, NCGS estimates (based on FAA data) the affected radius at 400 ft AGL to be approximately 72 NM and recommends adding a wide buffer (>10 NM) to that figure for operations near 400 ft AGL.
 

FAA issues notice of GPS interference testing
Tuesday, January 28, 2020
 
The Federal Aviation Administration (FAA) has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. For more details and a map showing the affected airspace, please see the advisory below.
 
FLIGHT ADVISORY
GPS INTERFERENCE TESTING
27 - 31 January 2020
Fort Bragg, NC

Additional information is available at the link below:

For unmanned aircraft operators, NCGS estimates (based on FAA data) the affected radius at 400 ft AGL to be approximately 65 NM and recommends adding a wide buffer (>10 NM) to that figure for operations near 400 ft AGL.
 

FAA issues notice of GPS interference testing
Monday, December 16, 2019
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY GPS INTERFERENCE TESTING
13 - 14 December 2019
Fort Bragg, NC

Additional information is available at the link below:
 

Please update your NCGS website bookmark
Tuesday, November 18, 2019

The NC Geodetic Survey website has undergone some recent back-end changes to enhance security and functionality. If you have not already done so, please update your bookmark for the NCGS page to the URL below.



FAA issues notice of GPS interference testing
Tuesday, September 17, 2019
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Norfolk Naval Base, VA that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY GPS INTERFERENCE TESTING
18 - 20 September 2019
Norfolk Naval Base, VA

Additional information is available at the link below:
 

FAA issues notice of GPS interference testing
Tuesday, August 27, 2019
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY GPS INTERFERENCE TESTING
26 - 30 August 2019
Fort Bragg, NC

Additional information is available at the link below:
 

FAA issues notice of GPS interference testing
Friday, April 26, 2019
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY GPS INTERFERENCE TESTING
28 April - 02 May 2019
Fort Bragg, NC

Additional information is available at the link below:
 

GPS Week Number Rollover
Thursday, March 28, 2019
 
The GPS Week Number will reset to zero at 23:59:42 UTC on April 6, 2019. Please visit the link below for more information. The GPS Week Number rollover information is at the top right of the page.
 
 

FAA issues notice of GPS interference testing
Tuesday, February 26, 2019
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY
GPS INTERFERENCE TESTING
21 February - 02 March 2019
Fort Bragg, NC.
Additional information at the link below:
 

High Water Mark Location Collection Tool
Wednesday, September 12, 2018
 
The high water mark collection tool can be accessed using the link below:
 
 

NCGS selects three firms for the aerial imagery quality control (QC) project
Thursday, May 31, 2018
 
The North Carolina Geodetic Survey selected the following private surveying firms for the aerial imagery quality control (QC) project (RFQ #295-01-2018):
 
CESI (Concord Engineering & Surveying, Inc.)
Merrick & Company
Vaughn & Melton Consulting Engineers, Inc.
 

2022 Datum Information Available
Monday, April 30, 2018
 
A new category has been added to the library specifically for information related to the 2022 datum change. In the document library, choose the "2022 Reference Frame" category from the dropdown menu. The information can also be accessed directly using the link below:

FAA issues notice of GPS interference testing
Wednesday, March 21, 2018
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY
GPS INTERFERENCE TESTING
22-23 March, 2018
Fort Bragg, NC.
Additional information at the link below:
 

FAA issues notice of GPS interference testing
Thursday, February 8, 2018
 
The FAA has issued a notice of GPS interference testing in the general vicinity of Fort Bragg, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
FLIGHT ADVISORY
GPS INTERFERENCE TESTING
11-15 February, 2018
Fort Bragg, NC.
Additional information at the link below:
 

Request for Qualifications (RFQ) issued for aerial imagery quality control (QC) project
Tuesday, January 23, 2018
  
The North Carolina Geodetic Survey (NCGS) intends to award multiple Qualifications-Based Selection (QBS) contracts to private surveying firms for the purpose of performing aerial imagery quality control (QC) surveys utilizing Global Navigation Satellite System (GNSS) and traditional survey methods to support the Statewide Digital Orthoimagery Project.​
 
The purpose of the orthoimagery project, which is funded by the North Carolina 911 Board (http://www.nc911.nc.gov/), is to collect seamless aerial imagery for use by local 911 agencies; local, state and federal agencies; and the public.
 
The work for this Request for Qualifications (RFQ) would consist of performing horizontal and vertical quality control (QC) survey projects.  For more information, please visit the following URL:
 
 

Informative videos available
Wednesday, November 8, 2017
 

A collection of short, informative videos about various topics have been made available. The videos can be accessed by clicking the links below:

 

Continuously Operating Reference Station (CORS) videos

 

FAA issues notice of GPS interference testing
Wednesday, September 13, 2017
 
The FAA has issued a notice of GPS interference testing by the Air Force in the general vicinity of Cherry Point, NC that​ may result in unreliable or unavailable GPS signal. Please see the advisory below for details.
 
Notice Number: NOTC7365
FLIGHT ADVISORY
GPS INTERFERENCE TESTING
AIR FORCE SPECTRUM MANAGEMENT OFFICE (AFSMO) 17-02
16-30 September, 2017
Cherry Point, NC.
Additional information at the link below:
 

Solar storm alert
Wednesday, September 6, 2017

Expected solar storm serves as a reminder to always check the space weather forecast before doing any GNSS surveying, precision agriculture, or GNSS-guided earthmoving work

The sun had a coronal mass ejection (CME) on September 4 that is expected to produce one or more geomagnetic storms on September 6 and 7.  The NOAA Space Weather Prediction Center (SWPC) has issued a G3 (strong) geomagnetic storm watch for this event.  
  
How does space weather affect GNSS work?  NASA provides the following response:
In calm conditions, single frequency GPS systems can provide position information with an accuracy of a meter or less.  During a severe space weather storm, these errors can increase to tens of meters or more.  Dual frequency GPS systems can provide position information accurate to a few centimeters.  In this case the two different GPS signals are used to better characterize the ionosphere and remove its impact on the position calculation.  But when the ionosphere becomes highly disturbed, the GPS receiver cannot lock on the satellite signal and position information becomes inaccurate.
 
Geomagnetic storms create large disturbances in the ionosphere.  The currents and energy introduced by a geomagnetic storm enhance the ionosphere and increase the total height-integrated number of ionospheric electrons, or the Total Electron Count (TEC).  GPS systems cannot correctly model this dynamic enhancement and errors are introduced into the position calculations.  This usually occurs at high latitudes, though major storms can produce large TEC enhancements at mid-latitudes as well.
 
Therefore, please always check the following SWPC webpages before doing any GNSS work:
·         3-DAY FORECAST
 

Update regarding NGS web services outage
Monday, September 12, 2016

 

The NGS HQ building experienced a fire event Friday Sept 9. All servers were shut down and limited user functionality such as CORS data, datasheets and geodetic utilities were switched to the backup systems in Boulder, CO. NGS is working on restoring full service sometime Monday Sept. 12.



Informative videos available
Friday, September 9, 2016

A pair of short, informative videos about EDMI baselines are now available. The videos can be accessed by clicking the links below:

 
The link below allows the user to download the NCDOT EDMI check program as a zipped file.



Meeting of the North Carolina Boundary Commission
Monday, July 25, 2016​
 
Notice is hereby given of a meeting of the North Carolina Boundary Commission
 
  


NCGS selects three firms for the aerial imagery quality control (QC) project
Friday, March 11, 2016

 

The North Carolina Geodetic Survey selected the following private surveying firms for the aerial imagery quality control (QC) project (RFQ #295-01-2016):

 

CESI

Stantec Consulting Services Inc.

Vaughn & Melton Consulting Engineers, Inc.

 

Request for Qualifications (RFQ) issued for aerial imagery quality control (QC) project
Thursday, January 28, 2016​

The North Carolina Geodetic Survey (NCGS) intends to award multiple Qualifications-Based Selection (QBS) contracts to private surveying firms for the purpose of performing aerial imagery quality control (QC) surveys utilizing Global Navigation Satellite System (GNSS) and traditional survey methods to support the Statewide Digital Orthoimagery Project.

The purpose of the orthoimagery project, which is funded by the North Carolina 911 Board (http://www.nc911.nc.gov/), is to collect seamless aerial imagery for use by local 911 agencies; local, state and federal agencies; and the public.

The work for this Request for Qualifications (RFQ) would consist of performing horizontal and vertical quality control (QC) survey projects.  For more information, please visit the following URL:

https://www.ips.state.nc.us/ips/AGENCY/PDF/11154000.pdf​


Web Link to North Carolina's Spatial Data Download
Thursday, January 28, 2016​

Users wishing to download NC spatial data may do so at the following link:

https://rmp.nc.gov/sdd/​


Informative videos available
Thursday, July 30, 2015

A series of short video tutorials are now available to help navigate the most-recently developed NC Geodetic Database. The videos can be accessed by clicking the link below:



Solar storm alert
Monday, June 1, 2015

Expected solar storm serves as a reminder to always check the space weather forecast before doing any GNSS surveying, precision agriculture, or GNSS-guided earthmoving work

 
The sun had a coronal mass ejection (CME) on June 18, 19, and 21 that we are experiencing as a series of geomagnetic storms.  The NOAA Space Weather Prediction Center (SWPC) announced on Monday, June 22, that "the geomagnetic storm began as forecasted and quickly ramped up to severe (G4) levels."  
 
On June 23, SWPC predicted the following over the June 23, 24, & 25 period:
The geomagnetic field is expected to remain agitated with G1-G2 (Minor - Moderate) possible early on day one (23 Jun) in continued response to the 21 Jun CME.  Conditions are expected to continue to gradually taper off below G1 (Minor) over the next 12-18 hours back to quiet to active conditions.  The 21 Jun CME is expected to arrive late on day two (24 Jun) to early on day three (25 Jun).  The CME will likely enhance geomagnetic conditions to G1-G2 (Minor-Moderate) levels with the possibility for stronger conditions on day three (25 Jun).
 
On June 24, SWPC predicted the following over the June 24, 25, & 26 period:
G1 (Minor) geomagnetic storms are expected with waning effects from past CME.  With the onset of the new CME, storming conditions up to G3 (Strong) are likely.
 
It is important to note that the SWPC reported the following in its June 23rd 3-Day Forecast, “No radio blackouts were observed over the past 24 hours.”  Furthermore, SWPC predicted a 75% chance of minor-moderate (R1-R2) radio blackout levels for June 24, 25, and 26 and a 20% chance of a strong (R3 or greater) radio blackout over the 3-day period.  SWPC explained, “R1-R2 (Minor-Moderate) or greater radio blackouts are expected, with a slight chance for R3 (Strong) radio blackouts on days one through three (24-26 Jun) due to flare potential from region 2371.
 
How does space weather affect GNSS work?  NASA provides the following response:
In calm conditions, single frequency GPS systems can provide position information with an accuracy of a meter or less.  During a severe space weather storm, these errors can increase to tens of meters or more.  Dual frequency GPS systems can provide position information accurate to a few centimeters.  In this case the two different GPS signals are used to better characterize the ionosphere and remove its impact on the position calculation.  But when the ionosphere becomes highly disturbed, the GPS receiver cannot lock on the satellite signal and position information becomes inaccurate.
 
Geomagnetic storms create large disturbances in the ionosphere.  The currents and energy introduced by a geomagnetic storm enhance the ionosphere and increase the total height-integrated number of ionospheric electrons, or the Total Electron Count (TEC).  GPS systems cannot correctly model this dynamic enhancement and errors are introduced into the position calculations.  This usually occurs at high latitudes, though major storms can produce large TEC enhancements at mid-latitudes as well.
 
 
 Chart.png

Therefore, it is advisable to not do any GNSS work over the next three days, if possible.  As for work that was conducted during the geomagnetic storm’s most severe periods (2:00 pm – 5:00 pm EDT on June 22 and 11 pm EDT on June 22 to 2:00 am EDT on June 23) that work may need to be repeated.
 
 
 
Therefore, please always check the following SWPC webpages before doing any GNSS work:
·         3-DAY FORECAST
 

NGS Releases New Beta Version of Transformational Tool
Monday, June 1, 2015

The National Geodetic Survey (NGS) is pleased to announce the Beta release of a new and improved transformation tool in the NGS geodetic toolkit. This redesigned version supports the transformation between geodetic coordinates and State Plane Coordinates (SPC), Universal Transverse Mercator (UTM) coordinates, Cartesian coordinates (XYZ), and U.S. National Grid (USNG) coordinates as a one-stop solution. It features transformation of single or multiple points, Web services, and software downloads. NGS encourages users to try the Beta Version and provide feedback to Krishna.Tadepalli@noaa.gov so the final version may be improved prior to release as on official NGS product.

The update was in the development stage for several months, and it provides surveyors and geodesists with a more efficient and streamlined way of accessing frequently used NGS tools in the geodetic toolkit. The new interface allows one-page easy access to transformations that were previously available only on separate pages.

The Beta version is accessible at: http://beta.ngs.noaa.gov/gtkweb


GEOID12B Released
Thursday, April 23, 2015

​From NGS

"When using the geoid models, please be advised that GEOID12B should supersede previous models GEOID12 and GEOID12A. GEOID12B is identical to GEOID12A everywhere, except in Puerto Rico and Virgin island region. For more detail, please read Technical details."

Visit the GEOID12B page at NGS: http://www.ngs.noaa.gov/GEOID/GEOID12B/


NC-SC Boundary Commision Meeting
Monday, March 23, 2015

MEDIA ADVISORY

WHAT: The joint boundary commission is a cooperative effort between North Carolina and South Carolina to reestablish our original common boundary, which is the official boundary, in order to minimize jurisdictional conflicts caused by the uncertain location of this boundary. The purpose of this meeting is to discuss the proposed legislation to be filed in each state to reduce impacts on those residents and property owners affected by the clarification of the boundary.
WHEN: Friday, March 27, 2015 10 a.m. to 2 p.m.
WHERE: Baxter Hood Center, Bowater Room
York Technical College
452 South Anderson Road
Rock Hill, SC 29730
AGENDA:
10:00 Welcome, introductions, and objectives for the day
Alan-Jon Zupan, meeting moderator and co-chair of the NC-SC Joint Boundary Commission
10:10 Review and discussion of the proposed legislation to minimize impacts on affected residents and property owners
11:30 Public Comments
12:00 Lunch
12:45 Discussion on the proposed legislation (continued)


GPS on Bench Marks Webinar
Tuesday, March 03, 2015

NOAA’s National Geodetic Survey encourages anyone with survey-grade Global Positioning System (GPS) receivers or GPS-enabled phones and hand held devices to help collect GPS on Bench Marks. This webinar will provide guidance to collect GPS observations at any time, including during National Surveyors Week (March 15–21, 2015). Joining the 2015 effort will help raise awareness about professional surveying while improving the National Spatial Reference System (NSRS).

To register and for more information on the webinar (March 5th, 3pm et), visit: http://www.ngs.noaa.gov/corbin/class_description/GPS_on_benchmarks.shtml.

For more information on GPS on Bench Marks, visit: http://www.ngs.noaa.gov/web/surveys/GPSonBM/.

NCGS