A critical operation is planned for later today. What preparations can I make within Verify-QC? After changing the L-band beam my RTCM station list is not fully populated, why is this? Does Verify-QC configure all my LD2/LD2S settings or are some manual entries required? How can I obtain a manual for Verify-QC v1.20? How do I add non-VERIPOS RTCM stations to the Verify-QC software? How do I archive data in Verify-QC? How do I check the version number of my Verify QC software? How do I configure an NTRIP RTCM input in Verify QC? How do I configure Verify QC to compute an Apex (Apex2) solution How do I configure Verify QC to compute an Ultra or Ultra2 solution? How do I extend the duration of or upgrade my Verify-QC dongle? How do I log RINEX data using the Verify-QC software? How do I setup Apex as backup within Verify QC? How do I upgrade my verify QC? How to Import Verify QC Config Files from a USB to an LD6 If I have too many windows open in Verify-QC, could this cause my computer to crash? I have rebooted my LD2, connected to Verify QC using the Ethernet Port and GNSS Rx in Calculation Status has turned red and stayed red. How do I get it green again? Tides - Can I change between Ultra and Apex? Tides - Can I use the Tides information in real-time? Tides - (How) does the Tides calculation compensate for Heave, Pitch and Roll? Tides - How do I configure and View Tides in Verify QC? Tides - How do I convert from MSS Tides to LAT? Tides - How do I know that MSS Tide and Geoid Tide give representative results? Tides - How do I know that the Tides calculation is giving continuous results? Tides-If I restart QC does Tides restart? Tides - We are leaving the work area to make a port call, should I reset Tides? Tides - What Antenna Height should be measured and what accuracy is required? Is this value fixed for the duration of a survey or should it be updated? Tides - What is the vertical reference for the VERIPOS Tides estimates? Tides-When will tides reset? Tides - Where can I find the Tides logging files? Verify-QC for LD6 Version User Manual Verify-QC v1.20 User Manual We have moved to a new area. Why am I not receiving corrections in Verify-QC? What are the new features of Verify-QC v1.20? What are the recommendations concerning Ultra Backup Positions in Verify-QC? What Geoid model is used within the Verify-QC software? What GNSS receivers does the Verify-QC software support? What is the current release verison of the Verify-QC software and where can I get a copy? What is the minimum specification for a PC to run Verify-QC? Is Windows Vista or Windows 7 supported? What is the purpose of the Tides function in Verify-QC? What is the Vio application included with Verify-QC and how can I use it? When I try to start Verify-QC, I receive a warning message about the dongle. What can I do? Why am I not receiving all the expected reference stations in Verify-QC? Why can’t Verify-QC compute an Ultra Position? Why is “Config” missing from my main menu in Verify-QC? Why is one section of the RINEX logging menu of Verify QC greyed out?

What is the purpose of the Tides function in Verify-QC?

VERIPOS Tides is a real-time tide estimation module within Verify-QC. The module uses the VERIPOS PPP high accuracy solution (e.g. Ultra or Apex) in conjunction with proprietary processing techniques to detect height variations relative to a vertical reference. Heights are typically determined to an accuracy of 10-20cm.

The VERIPOS Tides process provides two real-time tide observations relative to different vertical references.

The first method estimates the tide relative to a Geoid Model, either EGM96 or EGM08, which is a global approximation of MSS but only to the 2-3m level since it ignores the presence of Dynamic Ocean Topography. This observation, called Geoid Tide, is available instantaneously and is most suitable for short projects.

The second method first derives MSS using the VERIPOS Tide filter and then estimates the tide relative to this surface. This observation, called MSS Tide, is independent of uncertainties in the Geoid model. It does however require 39 hours of continuous Verify-QC operation and is therefore only suitable for longer-term offshore projects. The MSS Tide observation is more accurate since its vertical reference (MSS) is accurate at the cm level.

Recommendations on Using VERIPOS Tidal Estimates

An extensive range of tide and position related information is stored to file. This information allows users to incorporate relevant parameters into their real-time and/or post-process hydrographic data management activities and to do further calculations.

There are fundamental differences between real-time GPS-based tide estimation and a predicted tides model or a tide gauge. A predicted tides model will only calculate the predicted vertical movement of the sea surface caused by gravitation effects of mainly the sun and moon and ignore atmospheric and storm surge effects – hence a very smooth tidal curve is produced. A tide gauge can observe tide at a much higher frequency and correct for atmospheric pressure effects but may be effected by storm surge effects.

The VERIPOS Tides estimates provide the real-time total variation from a vertical reference (MSS for MSS Tide or EGM model for Geoid Tide). Fact is that the sea surface varies not only due to tidal effects but also due to additional effects like atmospheric effects (variations in pressure and wind) which in extreme cases will cause tidal surges.

The benefit of estimating a real-time total variation from a vertical reference is that a single vertical correction can be applied to marine survey depth information. In addition, VERIPOS Tides can be estimated with a high frequency, as low as once per minute, such that a very detailed sea surface variation pattern can be build up.