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Review of the General Assembly by the Division President

Review of the General Assembly by the Division President

More than 15.000 participants with great presentations in 666 sessions (posters, PICOs, and orals) made the EGU General Assembly 2018 at the Austrian Convention Centre in Vienna a great success.
In the geodesy-led programme, we had 428 submissions, which were distributed to 19 oral blocks, 3 PICO sessions, and a series of poster sessions. We listened to exciting talks, starting with geodetic theory on Monday morning and ending with presentations on VLBI and SLR observations to artificial objects in space on Friday afternoon. The PICO sessions with 2-minute (“madness”) introductions are attracting increasing interest, and the poster sessions in the evening made EGU 2018 a good place for discussions and networking. (Hopefully, there will be faster access to coffee and beer next year.)

As a central element of its General Assembly, EGU offered a series of Union Sessions, Interdisciplinary Events, Great Debates, and Short Courses. I always appreciate this possibility of seeing a bigger picture of geosciences. At the Division level, a Geodesy Reception was organised for the first time at TU Wien Tuesday evening with a nice view over the city. This event was well received, although some fine-tuning in the organisation is required to be able to repeat it in 2019. Highlights in geodesy were certainly the presentations of the Vening Meinesz Medal to Markus Rothacher and the Outstanding Early Career Scientist Award to Sara Bruni. Congratulations!

I really would like to thank everybody (participants, authors, conveners, Division Officers, …) for their contributions and fellowship with EGU. You make the EGU General Assemblies an extremely valuable event for geodesy! I hope you enjoyed EGU 2018 – recommendations and feedback (positive and negative) is highly appreciated (email to g@egu.eu).

Looking forward to seeing you in Vienna in April 2019,
Johannes Böhm

 

EGSIEM wants to use GRACE gravity field data for operational flooding and drought management

EGSIEM wants to use GRACE gravity field data for operational flooding and drought management

The terrestial water cycle leaves traces in the Earth’s gravity field

The current onset of el Nino is raising hope in California to replenish some of its multiyear water deficit. Due to the warm pool of water on the East side of the Pacific, more rain, and consequently also larger potential for flooding is expected. At the other side of the Pacific, the water is colder than usual leading to Australia bracing itself for a period of drought.

Besides sea surface height and temperature changes, these precipitation patterns move water masses which are even detectable in the time varying gravity field of the Earth. It would therefore make a lot of sense to integrate gravity field data within drought and flood monitoring schemes. The German-American Gravity Recovery and Climate Experiment (GRACE) already supplies this information, and has proven to be very valuable for climate studies. These range from studies of the mass variations of the world’s major ice sheets and glaciers and their impact on sea level, to studies focusing on anthropogenic uses of groundwater resources.

Near-real time availability of Gravity field data from GRACE opens up possibilities for flooding and drought management

GRACE is therefore very interesting for operational flooding and drought management,  however, the time it takes from the raw in-orbit GRACE measurements to become a widely usable product takes roughly 60 days. In order to embed this innovative gravity field data into operational systems this time needs to be reduced. In light of this, the EGSIEM consortium (European Gravity Service for Improved Emergency Management) are striving to provide a solution to the lack of prompt, uniform environmental mass redistribution data from the GRACE mission.

EGSIEM is a three year research and innovations project funded by the European Union under their Horizon 2020 Programme. It brings together around 20 scientists from geodesy and hydrology backgrounds around Europe who are taking a holistic approach to Earth Observation (EO) Data with the end goal of providing faster, standardized gravity field data. Such products may facilitate not only a broad scientific community, but are also of benefit for the general public who live in areas under threat of large-scale flooding and drought events. Changes in continental water storage conditions form (arguably) the most significant portion of mass redistribution data which, depending on local conditions, may lead to severe flooding and drought events. EGSIEM aims to demonstrate that observations of water and ice mass redistribution derived from satellite gravity data can provide critical and complementary information to more traditional EO products.

 

The GRACE twin satellite are accurately mapping tiny perturbations of the Earth's gravity field since 2002

The GRACE twin satellite have been accurately mapping tiny perturbations of the Earth’s gravity field since 2002

EGSIEM eases the acquaintance with gravity field data

“By offering improved and timely gravity fields, we want to encourage and open up novel approaches to flood and drought monitoring and forecasting” says Adrian Jäggi project coordinator of EGSIEM. The project’s main aims are: To provide a scientific combination service which will, using the knowledge of the entire European GRACE community, deliver a robust standardization of gravity-derived products. Reducing the current delays in provision of observations, such a near real-time service aims to reduce the average time of gravity field products from the current 60 days to five, and for initial Level 1 instrument data from 11 days to one. Also, by developing gravity based indicators for extreme hydrological events the EGSIEM team aim to demonstrate their value to flood and drought forecasting and monitoring services in a hydrological early warning service.

The EGSIEM team proactively maintain their impressive looking website (www.egsiem.eu), where scientists working in the field of gravity recovery and hydrology regularly post blog entries of their findings. According to Keith Cann-Guthauser who is the EGSIEM project administrator: “a key strength of EGSIEM is our engagement and effort to disseminate our findings to a larger audience.” The website further offers a direct visualization of satellite gravity field data with the EGSIEM plotter, and a possibility to sign up for a quarterly newsletter.

Keith Cann-Guthauser (front row second right) and Adrian Jäggi (front row left) are based at the Astronomisches Institut, Universität Bern.

Keith Cann-Guthauser (front row second right) and Adrian Jäggi (front row center) are based at the Astronomisches Institut, Universität Bern.

Measuring with sub-mm accuracy, who cares? WE DO!

Measuring with sub-mm accuracy, who cares? WE DO!

Welcome to the official blog of the geodesy division of the European Geoscience Union. Hosted by the EGU (thanks for that!), the blog is currently being brought into life by the geodesy division presidents and myself. Of course, anyone who has even the slightest curiosity towards geodesy is happily invited to pay us a regular visit.

To stigmatize right away, most geodesists will probably be, either directly or indirectly, involved in measuring the Earth (shape, gravity, rotation) with ridiculously accurate measurement equipment. As a result, geodesists tend to get very excited when they see numbers change somewhere in the 8 digit behind the decimal.

At first sight, this seems like a pretty boring occupation, but we would like to convince you of the contrary. By posting here, we want to convey findings of geodesy related research in an easy-to-digest format, and show the world that we (geodesists) are actually doing pretty interesting and highly relevant work. Furthermore, we’re looking forward to add some personal seasoning to the blog by providing, for example, insights into field work experiences. Of course, news from the EGU Geodesy Division itself will also be posted here. We’ll be on the lookout for interesting/important/funny/visual(!) stuff, but it will be even better if you contact us directly if you have something to share.