Photo: Saildrone

For the fourth consecutive year, Saildrone and the National Oceanic and Atmospheric Administration (NOAA) are sailing a fleet of uncrewed surface vehicles (USVs) into hurricanes to better understand how these storms develop, track and intensify.

Saildrone Explorer USVs are 23 ft long and carry a payload of sensors to measure air, surface and water temperature as well as humidity, barometric pressure, wind speed and direction, salinity and wave height. To withstand major hurricane conditions—winds over 110 mph and waves that exceed 50 ft—they have a shorter and stronger “hurricane wing,” similar to a reefed sail on a sailboat.

Saildrone USVs sail autonomously along prescribed routes, which Saildrone Pilots define according to weather conditions and to meet mission objectives. Saildrone’s science partners in the mission at NOAA’s Atlantic Oceanographic & Meteorological Laboratory (AOML) and Pacific Marine Environmental Laboratory (PMEL) will work closely with Saildrone Mission Control to guide the saildrones into oncoming hurricanes.

As the final group of saildrones was readied for deployment, Tropical Storm Debby was forming in the Gulf of Mexico. Just days after SD-1057 was deployed, the USV sailed through the eye of Hurricane Debby hours before the storm made landfall in Florida. Powered solely by renewable wind and solar energy, the Saildrone fleet will stay at sea for the duration of the mission, which will last through October 2024.

<p>The post Saildrone, NOAA initiate tracking of seasonal hurricane activity first appeared on GPS World.</p>

Photo: NOAA

Today, NOAA cartographers from the Marine Chart Division are converting paper nautical charts to a digital format and incorporating them into NOAA electronic navigational charts (NOAA ENC). NOAA created its suite of ENCs by digitizing its paper nautical charts. An ENC is a vector database that supports all types of marine navigation. Marine navigators can use the system to see their real- time position in relation to features on a chart.

Marine navigators using NOAA ENC. (Photo: NOAA)

By digitizing the paper Erie Canal charts, NOAA can now provide ENCs for the canal from Albany to Lake Ontario. As part of the digitizing process, NOAA cartographers standardized the chart scales covering the canal, moving away from the 64 irregularly shaped paper charts in chart 14786, New York State Canal System.

1:10,000 SCALE NOAA Custom Chart output near Waterford, New York. (Photo: USGS/NOAA)

The ENC is the primary nautical navigation product of the agency, which is ending the production and maintenance of its traditional paper and raster nautical chart products. The remaining paper charts are only being updated with critical corrections until they are fully canceled. Chart 14786 will be one of the last ones canceled, on Dec. 5, 2024.

Now, marine users are referred to the NOAA Custom Chart Application. It is an online map tool for users to create paper and PDF nautical charts derived from the official NOAA ENC.

<p>The post How NOAA is digitizing charts of the Erie Canal first appeared on GPS World.</p>

Photo: Saildrone and NOAA.

As Hurricane Beryl moved across the Caribbean, the National Oceanic and Atmospheric Administration (NOAA) has partnered with Saildrone to deploy seven hurricane-tracking saildrones in strategic locations.  

These unmanned surface vessels (USVs) are equipped with a specialized “hurricane wing” to withstand extreme wind conditions. The USVs are gathering real-time data on key atmospheric and oceanic parameters such as wind speeds, wave heights, temperature, pressure and salinity​. 

Hurricane Beryl 

Hurricane Beryl impacted Jamaica, the Cayman Islands and the Yucatan Peninsula. Residents were urged to complete preparations to protect life and property as the storm progressed. 

Two saildrones were deployed in the Gulf of Mexico, launched from St. Petersburg, Florida, and Port Aransas, Texas, and five more in the Atlantic Ocean and Caribbean Sea, launched from Jacksonville, Florida, and the U.S. Virgin Islands. These systems provide critical data to improve the understanding and prediction of tropical cyclone intensity changes, particularly rapid intensification — where hurricane wind speeds increase dramatically in a short period​. 

To enhance these efforts, Rutgers University deployed underwater gliders that work in tandem with saildrones. These gliders measure temperature and salinity at various depths, offering a detailed picture of the ocean’s conditions before, during and after a hurricane.  

The collaboration aims to provide high-resolution, coordinated measurements from the ocean surface to the atmosphere, enhancing situational awareness for forecasters and improving the accuracy of hurricane intensity forecasts. 

Our researchers flew into Cat5 Hurricane #Beryl w/ @NOAA_HurrHunter to gather data from the air, while a @saildrone and a @RutgersU sea glider gathered data from the ocean, and @NOAASatellites gathered data from space. #collaboration @NOAAResearch pic.twitter.com/gG8P0yM9wo

— NOAA Atlantic Oceanographic and Meteorological Lab (@NOAA_AOML) July 3, 2024

Advanced Technologies  

Equipped with a “hurricane wing,” Saildrone’s USVs can collect continuous data in harsh storm conditions, providing real-time insights into the physical interactions between the ocean and atmosphere. Underwater gliders, deployed by Rutgers, aid in measuring subsurface ocean conditions, which are critical for understanding how variations in temperature and salinity affect hurricane strength. 

The information gathered by these technologies is extremely valuable for enhancing predictive models, ultimately helping to improve disaster preparedness and response. The partnership between Saildrone, NOAA and Rutgers University represents a significant step forward in the use of uncrewed systems for environmental monitoring. 

Photo: Saildrone and NOAA

<p>The post Saildrone, NOAA and Rutgers improve Hurricane Beryl monitoring first appeared on GPS World.</p>

Photo: SonjaBK / iStock / Getty Images Plus / Getty Images

In my last newsletter, I highlighted the release of a beta version of a new NOAA CORS Network (NCN) Station Web Page. As demonstrated in my newsletter, each CORS in the NCN has its own page with data, metadata, maps and photos for that station displayed in a modular layout so information is easily found all in one location. This past month, I had the privilege of participating in a meeting with representatives from the American Association for Geodetic Surveying (AAGS), the National Society of Professional Surveyors (NSPS) and the National Geodetic Survey (NGS). As a Past President of AAGS and the current Chair of the AAGS Membership Committee, I participate in these quarterly meetings.

AAGS aims to lead the community of geodetic, surveying, and land information data users through the 21^st century. AAGS members develop new educational programs, including presentations, seminars, and workshops on topics related to geodetic surveying; and articles and papers that inform the membership of the latest scientific and technological developments and how to implement them in the most cost-effective and efficient manner.

In my previous newsletters, I have reminded everyone that time is running out to obtain a working knowledge of the new, modernized National Spatial Reference System (NSRS). The release of the new, modernized NSRS is only about a year away. As of July 2024, NGS plans to have a beta version of the new, modernized NSRS available around the summer of 2025 for users to test and evaluate new products and services. After enough testing has been performed, the new, modernized NSRS will be officially published – probably in early to mid-2026.

At the meeting, NGS highlighted some new products on its Alpha Preliminary Products site. The alpha site provides products that are useful for individuals who want to obtain a better understanding of the products that will be distributed as part of the new, modernized NSRS.

Some of my previous newsletters have discussed the Alpha product concept.  My September 2023 newsletter highlighted the first two Alpha products; that is, State Plane Coordinate System of 2022 (SPCS2022) and NGS Coordinate Conversion and Transformation Tool (NCAT).  As of June 2024, two more products have been added to the Alpha Preliminary Products site – “GEOID2022 Alpha” and “Alpha Values for EPP.”  The State Plane Coordinate System of 2022 (SPCS2022) is probably the most important to land surveyors.  There are significant changes between the SPCS2022 and the State Plane Coordinate System of 1983 (SPCS83). I will highlight the latest options in the alpha site later in this newsletter.

First, I want to bring attention to the importance of ensuring that the state’s legislation is modified or rewritten, if required, to include that the current horizontal and vertical datums are being replaced with the new, modernized NSRS. The “Learn More” button on the SPCS2022 Alpha site provides information about legislation.

On the “Learn More” site, NGS provides an SPCS legislation template.

Per personal communication with Michael Dennis, Ph.D., NGS SPCS2022 Manager, as of June 26, 2024, the following 12 states have have enacted into law NSRS modernization: Alaska, Idaho, Iowa, Kansas, Kentucky, Louisiana, Nebraska, North Carolina, South Dakota, Vermont, Washington, and Wyoming.

Users can download examples of actual new state legislation here.

Examples of legislation.

During the joint AAGS/NSPS/NGS meeting, Tim Birch, the executive director of NSPS, said that anyone who has questions about updating legislation for the new, modernized NSRS, including SPCS2022, can contact him directly. NSPS has experience working with agencies and individuals to develop legislation as indicated in the following statement on the NSPS website.

“We are the voice of the professional surveying community in the US and its territories. Through its affiliation agreements with the respective state surveying societies, NSPS has a strong constituency base through which it communicates directly with lawmakers, agencies, & regulators at both the national and state level. NSPS monitors and comments on legislation, regulation, & policies that have potential impact on the activities of its members and their clients, and collaborates with a multitude of other organizations within the geospatial community on issues of mutual interest.”

Tim’s contact information is provided on the NSPS home webpage: Staff List – National Society of Professional Surveyors (nsps.us.com).

As previously stated, the two latest alpha products are the “GEOID2022 Alpha” and “Alpha Values for EPP.” My December 2017 newsletter discussed GEOID 2022 and the North American-Pacific Geopotential Datum of 2022 (NAPGD2022), and my February 2022 newsletter discussed the Euler Pole Parameters process and use in the new, modernized NSRS.

The GEOID2022 Alpha page provides a version of GEOID2022, which is the most recent prototype of the geoid models. The reference ellipsoid is Geodetic Reference System 1980 (GRS 80, but the geometric reference frame is ITRF2020). The Alpha GEOID2022 prototype data is available for download in two formats, “ASCII” and “.b.” There is a static component (SGEOID2022) and a dynamic component (DGEOID2022). These grids will be useful to programmers who want to develop and test their systems. Additional grids and tools will be available in the future.

Technical Details of the Alpha prototype of GEOID2022

GEOID2022 alpha is the last prototype of GEOID2022. It covers three regions: the North America–Pacific region, Guam and Northern Mariana Islands, and American Samoa. The spatial resolution of the geoid model is 1 arcminute. The geoid heights, which are in the tide-free system, are with respect to the reference ellipsoid of the Geodetic Reference System 1980 (GRS80) in the ITRF2020 geometric reference frame. GEOID2022 alpha includes static and dynamic components for the geoid heights. For detailed fundamental parameters of the geoid model, refer to NOAA Technical Report 78.

GEOID2022 Alpha

The Alpha EPP site provides the Euler Pole Parameters (EPP) that are needed to define the relationship between the ITRF2020 and models on the North America, Caribbean, Pacific and Mariana plates as discussed in NGS’s Blueprint Part 1 document.

Alpha Values for EPP

As stated in Blueprint Part 1, NGS will define the official relationship between ITRF2020 and the four NSRS TRFs through equation 59, using the rotation matrix in equation 58 resulting in equation 60.

I programmed this using a simple Excel spreadsheet to compute some of the potential changes between epochs for North Carolina. They were very similar to the ones that I depicted in my February 2022 newsletter that discussed the Euler Pole Parameters process and provided plots depicting the movement.

I would like to highlight the latest information available on the State Plane Coordinate System of 2022 alpha site. As previously stated, in about a year, the new, modernized NSRS will be available as a beta product. Users must get prepared by accessing NGS’s alpha products as well as taking the opportunity to provide feedback to NGS to improve their products and services. The Online Interactive Maps page provides information about the zones for every U.S. state and territory.

Clicking on the Online Interactive Maps link opens a NOAA ArcGIS online website that provides information about the Alpha State Plane Coordinate System 2022 preliminary zone designs. I have highlighted a few items that may be of interest to users.

The site provides a description of the site, links to various types of zones, links to data sources and information about distortion.

SPCS2022 online interactive maps.

Clicking on the link for zone definitions provides a list of zones and their parameters. This same information is also provided when users click on a zone on the map. I will demonstrate this later in this newsletter.

Per personal communication with Dennis, as of June 26, 2024, seven states have some or all their SPCS2022 zone definitions formally finalized, consisting of 205 out of the 965 zones (the total number of zones is still preliminary):

• Alaska (partial coverage multizone layer)
• Arizona (both multizone layers)
• Idaho (both multizone and statewide)
• Kentucky (both multizone and statewide)
• North Carolina (statewide zone; it has no other zones)
• South Dakota (both multizone and statewide)
• Wisconsin (multizone)

Dennis informed me that the information on the alpha SPCS2022 Experience has been updated. He told me that the total number of zones decreased from 967 to 965, but based on coordination with the International Association of Oil & Gas Producers (IOGP) Geodesy Subcommittee the number may eventually increase to 972 (more about that in a future newsletter).

He stated that his goal is to finalize the zone definitions by the end of this calendar year or early 2025. Users should keep checking the alpha site.

Dennis mentioned that the website now offers a new feature that provides the distortion value when users click on the map. A nice thing about that is the site can be used on a smartphone, allowing users to obtain real-time distortion information from their location.

Clicking on the link titled “View” in the upper right corner of the box brings up a map that depicts the SPCS2022 zones.

View of ALPHA (preliminary) SPCS2022 zone designs.

When you click on the note about the ALPHA being preliminary, the map underneath appears where the user can select the type of maps they wish to review.

The following options are available: All Zone Layers, Statewide Zone Layers, Multizone Complete Layers, Multizone Partial Layers, and Special Use Zone Layers.

Users can use their mouses or the “+” button on the left-hand side” to zoom to a particular region, or use the search button on the right-hand side to select a State or zone.

Using the search box.

Information about a particular zone pops up by clicking on a point on the map.

Detailed information provided for a zone.

Each zone provides links to other features based on the location of the point selected on the map.

The image below provides the distortion in ppm for the point selected on the map.

The Alpha NCAT site can be used to obtain an estimate of the changes between SPCS83 and SPCS2022. It should be noted that all values will be in meters (m) and international feet (ft).

International feet may be new to some surveyors who were previously using the U.S. survey feet in SPCS83. The U.S. survey foot will not be used with the NSRS, including SPCS2022 coordinates. NGS and the National Institute of Standards and Technology (NIST) have taken action to deprecate the U.S. survey foot. What does that mean?. NIST has the following statement on its website: “Beginning on January 1, 2023, the U.S. survey foot should be avoided, except for historic and legacy applications, and has been superseded by the international foot.” This means that NGS will not be publishing SPCS2022 in U.S. survey feet but all historic products and services such as SPCS83 will still be provided in U.S. survey feet (sft) and international feet (ift).

More information and resources about the deprecation of the sft are listed below (personal communication from Dennis):

• The official announcement is the final determinationFederal Register Notice (FRN) on deprecation of the sft issued on 10/5/2020. It was jointly issued by the National Institute of Standards and Technology (NIST) and NGS. I encourage everyone concerned about this topic to read it closely and in its entirety; it can likely answer most questions. The FRN includes information on the continued use of sft for legacy applications (such as SPCS 83). That is stated in the last paragraph of the “Notice of Final Determination” section; in items #1 and #2 in the “Counterpoints to Feedback Expressing Opposition”section; and in the second paragraph of the “Implementation Summary and Actions” section.
• The legacy issue is also addressed in the 10th FAQon the NIST website and in the 11th FAQon our “new datums” FAQs web page.
• The 40 states that officially adopted the sft for SPCS 83 are listed in Table C.1 of Appendix C of NOAA Special Publication NOS NGS 13, “The State Plane Coordinate System History, Policy, and Future Directions.”
• Although the final determination FRN is itself not a law, Congress has passed several laws giving NIST the authority to maintain national standards of measurement. These and other related federal laws are given in the initial sft FRNissued on 10/17/2019.
• An NGS webinar given on 11/10/2022 addresses the deprecation of the sft in the context of state plane. Two previous NGS webinars also provide additional background and historical information on the sft, one given on 4/25/2019 and the other on 12/12/2019.

Input to Alpha NCAT.

Photo:Output from Alpha NCAT.

This newsletter highlighted the products on NGS’s Alpha Preliminary Products site. The alpha site provides products that can be useful for individuals to obtain a better understanding of the products that will be distributed as part of the new, modernized National Spatial Reference System (NSRS). NGS is providing these products on an alpha site so that they can get feedback from users. I would encourage all users to access the alpha sites and provide comments to NGS so that their products and services better meet the needs of the surveying and mapping community.

Alpha Preliminary Products

Welcome to the NGS National Spatial Reference System (NSRS) Modernization Alpha Product Release Site. This site provides examples of the content, format, and structure of data and products that NGS plans to release as a part of the Modernized NSRS.

Products found on this page are for illustrative purposes only and do not contain any authoritative NGS data or tools. They are under active development and are subject to change without notice.

To provide feedback on any of the content on this site, please email ngs.feedback@noaa.gov.

<p>The post NGS new alpha preliminary products in support of the modernized NSRS first appeared on GPS World.</p>

I mentioned in the May 2024 newsletter that NGS announced the release of a beta version of a new NOAA CORS Network (NCN) Station Web Page. Each CORS station in the NCN will have its own page with data, metadata, maps and photos displayed in a modular layout so information is easily found in one location. This newsletter will describe some features of the new beta site.

The beta site is located here.

I will highlight some of the information provided by the routine, but I would encourage others to access the beta site and provide feedback to NGS. NGS states on the site that “This is a Beta product. We are interested in your feedback. Please email us at: ngs.feedback@noaa.gov and indicate the subject as “NCN Station Pages Feedback.”

When you access the website, it defaults to the CORS station GODE. The user has the option to enter their own CORS station in the box located on the right-hand side of the webpage.

Texas CORS Station TXLV.

A nice feature of the site is that the CORS data availability for the last seven days is provided under the Station Information section. For those interested in downloading data, there is a button titled “Quick Data Download,” on the top left corner. The site allows users to download daily data from the past 30, seven or two days.

In my example, I downloaded the last seven days of data for CORS TXLV. It only took a few seconds to download and provide the data in a zipped file. If a user includes this process in their standard operating procedure, they can easily download all the CORS data required for their project.

Downloading TXLV GNSS data.

Another planning tool available is the weather information for a week. Today, most users can get the weather information on their phone. However, this is a convenient option to have when you are looking at available CORS on the day of occupying marks. It can help in managing schedule changes.

There is an option to show the five nearest CORS relative to your selected CORS by clicking on the button titled “Show Closest 5 on Map.”

CORS Located near TXLV.

Clicking on the button labeled “Show Legend” provides information about the CORS depicted on the map. This is a useful feature especially if selecting CORS that provide GNSS data other than GPS and/or data at different sampling rates.

If a user clicks on the button “Open NGS Map,” the site will access the NGS Map website and provide information about the selected CORS. This allows users to get information about the CORS. I found that the beta site provided most of the same information using the various options on the NGS Map website.

NGS Map depicting CORS TXLV.

The site provides photos and equipment history that may help in troubleshooting an issue associated with processing sessions or during the analysis of the adjustment results. I have highlighted that a new antenna was installed at the TXLV CORS on August 5, 2021. I will explain later in this newsletter how this information helped me during my analysis of a GNSS project.

Photos and equipment history of TXLV.

Under the Coordinates and Velocities section, the site provides information about the latest coordinates and velocities along with superseded values for the selected CORS. The superseded values may not be of interest to most users, but I am always looking at the changes in CORS coordinates. It is my nature to try to understand the reason why something has changed; especially for CORS that I am including in a GNSS project.

Coordinates and velocities.

Clicking on the link titled “Position and Velocity” under the Coordinates and Velocities section provides the coordinate and velocity information for your selected CORS. I have highlighted the ITRF2014 velocities, the NAD 83 (2011) velocities, the latest antenna type, installation date and the dates the positions and velocities were revised.

As shown in the image above, the position and velocity sheet provide the dates that the position was revised. Clicking on the link titled “Datasheet with GRP/MON included (if available)” in the Coordinates and Velocities section provides the datasheet that lists the NAD 83 (2011) superseded survey control values. The superseded ellipsoid heights from the datasheet are provided in the box titled “Excerpt from TXLV Datasheet.”

When you are trying to estimate heights to the 2 cm level, changes in published NAD 83 (2011) CORS heights at the 2 cm level are significant and should be investigated and understood. This beta CORS website offers useful information that can help understand some of these changes. I will explain later in the newsletter how this information and other data from the beta site helped me in the analysis of my GNSS project.

Excerpt from TXLV data sheet.

The beta site provides plots that depict the daily positions and residuals for a CORS. In my May 2024 newsletter, I stated that NGS has developed a Beta CORS Time Series Tool that provides information that assists users in selecting appropriate CORS for a project. The Beta CORS Time Series Tool provides the residual differences from the daily NGS OPUS-NET solutions with the coordinates from the official CORS’ coordinate functions. The excerpt below explains the plots and residuals:

NCN Residual Time Series Comparison Tool (NCN PloTS)

This tool computes and displays the residuals for up to 50 CORS stations within the NCN. The mean, standard deviation, and root-mean-square error of the residuals are also provided in a summary table that is available for download. This tool is informational, not authoritative.

The residuals are calculated as the difference between the daily observation at a station and the official daily coordinates for a station. The daily observation is processed from the GPS L1 and L2 signals only, using a network adjustment program. There must be a minimum of 8 hours of data present in a 24 hour file for a solution to be generated. The network adjustment program is an internal application developed by NGS for monitoring the position of the CORS stations in the NCN (Gillins et al., 2019). The official daily coordinates for a station are calculated using the reference epoch (2010.0) position and velocity published as the station coordinate function in the Position and Velocity File. An example of a Position and Velocity File for NCN station GODE can be found here. To obtain Position and Velocity Files for NCN stations please visit the NCN Station Pages and navigate to the Coordinates and Velocities section.

This tool is optimized for plotting data extending between 30 to 90 days in length but can be customized to other time frames. The earliest start date currently available is October 27, 2018, which is the completion date of the MYCS2 and the end date can be as recent as 3 days before the present day. This three-day time lag is so that the final orbits can be used in the network adjustment to create the daily solutions. Then, please enter the 4-character station ID for at least one and up to 50 CORS stations in the NCN and submit this request to obtain a map, summary table of comparative statistics, and residual plots during the date range.

The beta NGS NCN station pages show similar plots to the Beta CORS Time Series Tool. the station pages also allow users to create position and residual plots at different periods. I find these plots very useful when selecting CORS to be included in a GNSS project. The latest plots are of interest to users when selecting CORS to be included in their GNSS project but there are reasons to look at plots depicting older time periods.

Position and residual plots for TXLV.

I previously mentioned that the antenna of CORS TXLV was changed on August 5, 2021, so I used the option to plot the last five years to include data before and after the date the antenna was changed. I highlighted August 7, 2021, on both plots. This was two days after the antenna was changed on CORS TXLV.

There appears to be a 2 cm upward shift in the up component after the new antenna was installed. There was also a change of about 1 cm in the north component. Something else to notice in the position plot is that the east component has a significant tilt during the five years. The below provides the ITRF2014 velocities — the eastward component velocity is —1.21 cm/year. In 5 years, one could expect to see about a 6 cm change.

Position and residual plots for TXLV.

Five-year position plot of TXLV.

Five-year residual plot of TXLV.

Position plot of TXLV for selected time interval.

These small changes affected my analysis and network adjustment results. During the past several years, I have participated in several Harris-Galveston Subsidence District (HGSD) GNSS projects performed in the Houston-Galveston, Texas, region. I have been involved with estimating subsidence in the Houston-Galveston, Texas, region for about 40 years so when I see changes in height values indicating an apparent uplift it makes me question my results. Therefore, I started investigating the CORS involved in the GNSS project. I looked at the Texas CORS surrounding the GNSS project: WHARTON CORS, COLUMBUS CORS, HEMPSTEAD CORS, LIVINGSTON CORS, and LIBERTY CORS.

The table below provides the differences between the published ellipsoid height and the previous superseded height for the five CORS. As the table indicates, the published ellipsoid height of the CORS increased by about 2 cm from the superseded height. This led me to use the NGS NCN Station Pages to investigate these CORSs. I found that all five of these CORSs had new antennas installed in 2021 and their position plots depicted a similar shift.

I want to emphasis that I am not saying that anyone did anything wrong or incorrect.  The CORS manager of these sites provided the appropriate metadata to the NGS CORS team so the site information could be updated and correctly reported. What this indicates to me is that the installation of the new antenna and setup may have affected the height component of these CORS, that is, it may have changed the official position of the monument’s reference point. Again, I want to emphasize that I am not saying that anyone did anything wrong or incorrect.  NGS’s process includes monitoring all CORS that are part of the NOAA CORS Network (NCN). The NGS CORS Team noticed the significant change in the up component comparing it to its expected value, so they computed a new coordinate and published the new coordinate in 2022. In my opinion, anyone using these CORSs as constraints in their GNSS projects after the date that the new antenna was installed and before the new coordinate was published could have generated adjusted heights that are in error by 2 cm. As previously stated, when you are estimating heights to the 2 cm level, changes in published NAD 83 (2011) CORS heights at the 2 cm level are significant. In my opinion, this type of analysis should be performed by all users that are incorporating CORS in their GNSS processing.

Keep checking NGS beta site because NGS makes changes based on user feedback. As I previously stated, I would encourage everyone to access the beta site and provide your feedback to NGS. NGS states on the site that “This is a Beta product. We are interested in your feedback. Please email us at: ngs.feedback@noaa.gov and indicate the subject as “NCN Station Pages Feedback.”  I have talked to the CORS team and they really would like feedback. The team will make changes to the website based on feedback from users.

<p>The post NGS beta version of a new NOAA CORS Network station web page first appeared on GPS World.</p>

Photo: Verizon

The National Oceanic and Atmospheric Administration (NOAA) has entered into a three-year Cooperative Research and Development Agreement (CRADA) with Verizon Frontline to refine the use of uncrewed aircraft systems (UAS) for assessing storm damage. This initiative aims to provide rapid and accurate damage assessments following severe weather events such as tornadoes and hurricanes.

Verizon Frontline will deploy its UAV technology to capture high-resolution imagery of areas affected by storms, providing crucial data to NOAA’s National Weather Service (NWS) and the National Severe Storms Laboratory. This imagery will assist in post-storm damage assessments and contribute to research aimed at understanding tornado behavior and improving severe weather warnings.

“Following a crisis, the initial imagery available is often from satellites, which may not offer the best resolution. Our goal with NOAA is to provide high-resolution imagery much faster, enhancing the support to emergency management and public safety agencies,” said Verizon Frontline Crisis Response Team member, Chris Sanders.

The collaboration represents a step forward in integrating modern technology into traditional environmental and emergency management practices, aiming to improve outcomes after natural disasters.

<p>The post NOAA, Verizon Frontline enhance storm damage assessment first appeared on GPS World.</p>

NASA’s Solar Dynamics Observatory captured this image of solar flares on May 11, 2024. The NOAA says there have been measurable effects and impacts from the geomagnetic storm. (Photo: Solar Dynamics Observatory)

Earth is experiencing a severe solar storm causing concern for those responsible for power grids, communication systems and satellites.

The National Oceanic and Atmospheric Administration (NOAA) has reported measurable effects and impacts from the geomagnetic storm that has been visible as aurora across vast swathes of the Northern Hemisphere. As of May 12, 2024, NOAA had seen no reports of major damage.

There has been some degradation and loss to communication systems that rely on high-frequency radio waves, NOAA told NPR, as well as some preliminary indications of irregularities in power systems.

“Simply put, the power grid operators have been busy since yesterday working to keep proper, regulated current flowing without disruption,” said Shawn Dahl, service coordinator for the Space Weather Prediction Center at NOAA.

“Satellite operators are also busy monitoring spacecraft health due to the S1-S2 storm taking place along with the severe-extreme geomagnetic storm that continues even now,” Dahl added, saying some GPS receivers have struggled to lock locations and offered incorrect positions.

As NOAA warned, the Earth has been experiencing a G5, or “extreme,” geomagnetic storm. It is the first G5 storm to hit the planet since 2003, when a similar event temporarily knocked out power in part of Sweden and damaged electrical transformers in South Africa.

As of May 13, NOAA’s Space Weather Prediction Center said that a G3, or “strong,” geomagnetic storm warning was in effect until 2 a.m. ET. While stronger storms are no longer likely and conditions are expected to “gradually wane” throughout the day, the center said in its forecast that moderate to strong geomagnetic storms are “likely” on May 13, as are minor storms on May 14.

The center also said that “solar activity is expected to be at high levels” with a possibility of more solar flares, or bursts of electromagnetic radiation from the sun.

The update came as another X-class solar flare was recorded. X-class flares are the strongest class of these solar bursts, and the latest was recorded as “moderate.”

Flares of this magnitude are not frequent,” the center said. “…Users of high frequency (HF) radio signals may experience temporary degradation or complete loss of signal on much of the sunlit side of Earth.”

Northern lights in unusual places

On May 12, people from all around the world shared photos of a dazzling display of the Northern Lights, which were visible in Russia, Scandinavia, the United Kingdom, continental Europe and some even reported seeing the aura as far south as Mallorca, Spain.

In the United States, the NOAA center shared that the storm-induced auroras were visible as far south as Northern California and Alabama.

The source of the solar storm is a cluster of sunspots on the sun’s surface that is 17 times the diameter of Earth. The spots are filled with tangled magnetic fields that can act as slingshots, throwing huge quantities of charged particles toward our planet. These events, known as coronal mass ejections, become more common during the peak of the Sun’s 11-year solar cycle.

While the storm has proven to be large, predicting the effects of such incidents can be difficult, Dahl said.

The world has grown more reliant on electronics and electrical systems. Depending on the orientation of the storm’s magnetic field, it could induce unexpected electrical currents in long-distance power lines. Those currents could cause safety systems to flip and trigger temporary power outages in some areas.

I took these photos near Ranfurly in Central Otago, New Zealand. Anyone can use them please spread far and wide. https://t.co/NUWpLiqY2S

— Dr Andrew Dickson reform/ACC (@AndrewDickson13) May 10, 2024

The storm caused some navigational systems in tractors and other farming equipment to break down, suppliers and farmers told the New York Times.

Farmers have become dependent on equipment that utilizes GNSS and other navigation technology to help them plant more effectively — a practice known as precision agriculture. However, some of these operations in the Midwest, as well as in other parts of the United States and Canada, came to a temporary halt.

How it affects the ionosphere

The storm will also likely disrupt the ionosphere, a section of Earth’s atmosphere filled with charged particles. Some long-distance radio transmissions use the ionosphere to “bounce” signals around the globe, and those signals can be disrupted.

The particles may also refract and otherwise scramble GNSS signals, according to Rob Steenburgh, a space scientist with NOAA. Those effects can linger for a few days after the storm.

The storms can bring on ionospheric scintillation, which refers to rapid fluctuations in GNSS signal strength and phase due to localized irregularities in the electron density of the ionosphere resulting from solar activity. Scintillation adversely affects GNSS positioning, particularly around the geomagnetic equator after local sunset.

Similarly to Dahl, Steenburgh said that it is unclear just how bad the disruptions will be. While we still depend on GNSS, there are also more satellites in orbit. Moreover, the anomalies from the storm are constantly shifting through the ionosphere like ripples in a pool. “Outages, with any luck, should not be prolonged,” Steenburgh said.

<p>The post How the strong solar storm could impact GNSS first appeared on GPS World.</p>

Summary of the SIO Geospatial Award. (Image: NGS website)

Bock is director of the California Spatial Reference Center (CSRC), which is responsible for “establishing and maintaining an accurate state-of-the-art network of GPS control stations for a reliable spatial reference system in California.” I highlighted the CSRC in my June 2023 GPS World Newsletter.

Yehuda’s proposal included the following three activities:

• Create a formal Geodesy Program at SIO to address the nationwide deficiency of geodesists. Expand current geophysics curriculum – funding for five graduate students.
• Develop an IFDM to supplement the NSRS for users in regions with significant ground motions, using GNSS and InSAR/GNSS displacement fields (funded by NASA projects) and underlying geophysical models. CSRC will exercise the IFDM through its community of public, private and academic users of precise spatial referencing in our challenging region of secular and transient crustal movements.
• Investigate a unified vertical reference frame, including a marine geoid optimized to be consistent with the full spectrum of observations from modern gravimetric geoids (e.g., GRAV-D, ICGEM), remotely sensed observations (e.g., SWOT, ICESat-2), in situ ocean observations and assimilating ocean models and the TRF.

Yehuda’s project includes creating a formal geodesy program at SIO that will help to address the geodesy crisis. Anyone keeping up with my columns knows that I have been highlighting the geodesy crisis and programs that advance the science of geodesy (July 2020, November 2022, and December 2022).

Yehuda showed a slide that highlighted “What Geodesy Can Tell Us About Earth.”  Looking at the slide, geodesists are needed in the field of climatology, meteorology, hydrology, geology, volcanology, oceanography, and glaciology, as well as surveying, mapping, and navigation. All these disciplines study Earth’s dynamic processes and involve geodesy.

From Yehuda Bock Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

The images “Geodesy Curriculum at SIO (PhD, MSc)”, “Geodesy Courses – 1” and “Geodesy Courses – 2” provide information about the Geodesy Program as SIO.

From Yehuda Bock, Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

Notice that some of the courses focus on topics that are important to real world applications. For example, GNSS precise point positioning applications to seismotectonics, GNSS signal propagation applications to atmospheric remote sensing and GNSS reflection: soil moisture and sea level and the vertical datum.

From Dr. Yehuda Bock Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

FromYehuda Bock, Ph.D.’s presentation to the AAGS General Membership Meeting. (Image: AAGS website)

In addition to the graduate-level courses, they are proposing an undergraduate course titled Geodesy and Geospatial Information. The purpose of the course is to provide students with the skills in geospatial systems that will provide opportunities for eventual employment in the public and private sectors.

Proposed Undergraduate Course

 Title: Geodesy and Geospatial Information

Course justification and content objectives: Geodesy is the study of Earth’s size (geometry), shape (gravity field) and deformations (e.g., plate tectonic motions, subsidence). It provides access to a well-defined spatial reference system for precise geospatial information (latitude, longitude, height, elevation with respect to sea level) used for positioning, navigation, surveying and mapping. Geodesy is also an important discipline within the earth, atmospheric and oceanographic sciences, using observations of GPS and other satellite navigation constellations, remote sensing platforms (satellite and drone), and various terrestrial sensors. It is a data- and analysis-intensive discipline increasingly requiring modern data science methods. This introductory course will provide students with a solid background in geospatial systems for eventual employment in the public and private sectors. The course will also serve as a pipeline to the geodesy track at SIO/Earth Sciences and to other academic institutions and to alleviate the nationwide deficiency of geodesists. The objective is to provide basic knowledge of geodetic concepts for Earth and data scientists and the underlying geodetic framework for precise spatial information.

Learning objectives:

• Acquire basis concepts of geodetic science.
• Provide overview of geodetic instrumentation and observations.
• Develop elementary skills in geodetic data analysis.
• Explore existing geodetic infrastructure and data repositories.
• Experience hands on visualization and manipulation of geospatial information.
• Understand the underlying geodetic framework for precise spatial information systems.
• Provide example of data science applications in solving geodetic problems.

Preferred background: statistics, linear algebra, Matlab/Python

In my opinion, universities should provide a general elective course for undergraduate students that provides an introduction in how geodesy influences your daily routines. For example, how does my phone know where I am and how does it know the best route I should take to get to my destination?

How Does My Phone Know Where I Am? (Image: Dave Zilkoski)

The second task in the SIO proposal is to develop an IFDM. The concept of an IFDM is part of NGS’ modernized, NSRS. Several of my previous My July 2023 GPS World newsletter highlighted a presentation by Yehuda discussing a kinematic datum that uses an intra-frame velocity model to estimate positions at any time with respect to a reference frame and epoch.

As I mentioned in my July 2023 newsletter, California’s geodetic network is significantly affected by crustal movement. To help address this issue, the CSRS updated the NAD 83 coordinates, it is denoted as CSRS epoch 2017.5 (NAD 83). Part of the implementation of the CSRC epoch 2017.50 (NAD 83) was to have the new epoch-date coordinates transmitted with RTCM 3.0 data streams. This is something that other RTN operators from around the nation will have to do after NGS publishes the NSRS coordinates. The CSRS is a model from which others can learn.

During his presentation to AAGS, Yehuda highlighted his methodology of integrating InSAR and GNSS to develop an IFDM that provides for higher spatial resolution to improve the model between GNSS stations.

The boxes titled “SCIP Dynamic Datum Utility” and “Output from SCIP Utility” provide an example of an input and output of the utility, and the box titled InSAR/GNSS Integration for Higher Spatial Resolution” is a conceptual diagram of the concept.

Not only has this abbreviation been spelled out before, but here the full phrase appears three times, in three consecutive sentences.

SCIP Dynamic Datum Utility. (Image: SOPAC website)

Output from SCIP Utility. (Image: (SOPAC Website)

From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting
(Image: AAGS website)

The image provides an example of the concept in the San Joaquin Valley, California.

InSAR/GNSS Integration Example.

The following statement is in the note section of the slide:

“Area of subsidence in San Joaquin Valley. Our weekly displacement time series at GNSS station P056 shows significant changes in subsidence rate over the period 2006 to 2022, for a total of 3.3 feet that reflects periods of drought and increased groundwater use. On the upper right is the InSAR time series at that location for a shorter period of time.”  This shows the potential of using InSAR to improve the IFDM in areas of sparse CORS.

The third item in the proposal is to “Investigate a unified vertical reference frame, including a marine geoid optimized to be consistent with the full spectrum of observations from modern gravimetric geoids (e.g., GRAV-D, ICGEM), remotely-sensed observations (e.g., SWOT, ICESat-2), in situ ocean observations and assimilating ocean models, and the TRF.”

The images below provide a list of the reference surfaces involved in unifying the vertical reference frames and the observing systems involved in the project. Understanding the geoid at the land-sea interchange is important to estimating accurate GNSS-derived orthometric heights along the coast as well as in the oceans. My August 2021 newsletter highlighted the concept of establishing an International Height Reference System (IHRS) so that all countries could provide physical heights across their boundaries and over the oceans. This project would support that international activity.

From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

From Yehuda Bock Ph.D.’s Presentation to the AAGS General Membership Meeting. (Image: AAGS website)

This newsletter and my previous GPS World newsletter highlighted two of the grantees, \SIO and OSU, which included developing models to address what NGS denotes as the IFDM.

The SIO program includes creating a formal geodesy program at SIO that will help to address the geodesy crisis. In addition to the graduate level courses, they are proposing an undergraduate course that will provide students with the skills in geospatial systems that will provide opportunities for eventual employment in the public and private sectors. My next newsletter will address another NGS geospatial modeling grant awardee – Oregon State University’s proposal.

<p>The post Scripps Institution of Oceanography establishes a geodesy program first appeared on GPS World.</p>