gravity

High resolution terrestrial water storage changes from combination of GRACE and models

Khosro Ghobadi-Far, edited by Öykü Koç and Bramha Dutt Vishwakarma February 7, 2024

Image credits: Jakob Keck (distributed via imaggeo.egu.eu)

The Gravity Recovery and Climate Experiment (GRACE) satellite mission (2002-2017) consisted of two satellites at ~500 km altitude separated by 200 km, following each other in the same orbit. The distance between the two GRACE satellites changes because of the gravitational pull of the masses beneath the satellites. As such, mass changes at or near the Earth’s surface caused variations in the dista ...[Read More]

Geodesists on Tour: On a Campaign in the Arctic with a Giraf(f)e in the Aircraft

Tim Jensen and edited by Rebekka Steffen November 6, 2023

First view of the Greenland east coast after crossing the Denmark Strait

Way too early on a Saturday morning in late June 2023 I woke up and started my travel to a small airport in Akureyri, North-East Iceland. This is the location of an Icelandic charter company called Norlandair that we used for our airborne geophysical surveys and logistic operations in the Arctic. For a few months I had been preparing a survey to test a new quantum-based technology for airbo ...[Read More]

Want to really understand sea-level rise? Bring in the geodesists!

Thomas Frederikse and edited by Rebekka Steffen September 28, 2022

Trends in sea level over 2005-2019 using satellite altimetry and gravimetry data.

A remarkably large number of papers and proposals have sentences like “this study is critical to better project future sea-level rise” in their introduction. Most times this is just marketing to trick reviewers and program managers into believing the work is important. On the other hand, geodetic papers and proposals have some compelling reasons to use this statement: a lot of geodetic tech ...[Read More]

Geodesists on Tour: On the left side of the road for getting the g

Przemysław Dykowski and edited by Rebekka Steffen January 24, 2022

A10-020 absolute gravimeter a gravity station near Newport (Ireland).

Getting the small g (the absolute gravity value) outdoors has always been some sort of a challenge. But, in the early 2000s the possibility to measure gravity has changed by the arrival of the first A10 absolute gravimeters. They to a large extent revolutionized the approach of performing gravity measurements in the open field and with that improved the approach to design and measure national grav ...[Read More]