Measuring tidal displacement using GPS

May 07, 2013

GPS is making possible high-precision, high-resolution measurements of tidal displacement that could not be achieved with other methods. Earth's surface deforms due to both body tides-the deformation of the solid Earth due to the pull of the Sun and the Moon-and ocean tides-the redistribution of water mass loading over Earth's surface. Body tides and ocean tides both have components that vary on semidiurnal, diurnal, and longer periods.

Yuan et al. used data from 456 globally distributed continuous GPS stations covering the period from 1996 through 2011 to determine the 3-dimensional crustal displacements for semidiurnal and diurnal tides.

They examined the accuracy and possible sources of error in the GPS-based estimates of tidal displacements, and were able to achieve sub-millimeter precision for the first time.

They also compared the GPS-based estimates with model accuracies of both body tides and and demonstrated that the GPS-based tidal displacements are more accurate than the modeled displacements, hence providing observations that could be useful for improving the models.

Explore further: Location matters in the lowland Amazon

More information: The tidal displacement field at Earth's surface determined using global GPS observations, Journal of Geophysical Research-Earth Surface, doi:10.1002/jgrb.50159, 2013 http://onlinelibrary.wiley.com/doi/10.1002/jgrb.50159/abstract

Related Stories

Out on the pull: Why the moon always shows its face

Mar 27, 2013

Technically, Pink Floyd had it wrong. The space-facing side of the moon isn't dark (except at full moon when the Earth is between the sun and the moon). Not that you'd know that, given we always see the same ...

Using Loch Ness to track the tilt of the world

Jan 02, 2012

That the rise and fall of the tide is primarily driven by the gravitational pull of the moon and the Sun is common knowledge, but not all tides are controlled by such a standard mechanism.

Ocean mavericks in Maine turn tide for electrical grid

Sep 19, 2012

(Phys.org)—Sadly speaking, the U.S. ocean-energy industry has had to take a back seat to Europe, where government subsidies help entrepreneurs and innovative companies work on their technologies. Happily ...

Rapid tsunami warning by means of GPS

Apr 25, 2012

For submarine earthquakes that can generate tsunamis, the warning time for nearby coastal areas is very short. Using high-precision analysis of GPS data from the Fukushima earthquake of 11 March 2011, scientists ...

Recommended for you

Severe ozone depletion avoided

15 hours ago

We are already reaping the rewards of the Montreal Protocol, with the ozone layer in much better shape than it would have been without the UN treaty, according to a new study in Nature Communications.

Location matters in the lowland Amazon

May 25, 2015

You know the old saying: Location, location, location? It turns out that it applies to the Amazon rainforest, too. New work from Carnegie's Greg Asner illustrates a hidden tapestry of chemical variation across ...

Quake rattles nerves in Napa Valley after 2014 disaster

May 22, 2015

A magnitude-4.1 earthquake has jolted Napa Valley and became an unwelcome reminder of the wine country's large temblor last summer—the strongest quake to hit Northern California in a quarter-century.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.