Location: Delft, The Netherlands
Type of contract: One year under Dutch Law
We are looking for an enthusiastic individual with experience in (geo)statistics and data analysis and knowledge of hydrogeology to support the implementation of the Global Gravity-based Groundwater Product (G3P) project, and the development of guidelines for a global groundwater quality assessment under the support of the Friends of Groundwater (FoG) workstream of the World Water Quality Alliance.
The G3P project is a EU HORIZON 2020 project that aims at developing a product of groundwater storage variations with global coverage and monthly resolution from 2002 until present. This is done by a cross-cutting combination of GRACE1 and GRACE-FO2 satellite gravity data with water storage data that are based on the existing portfolio of the Copernicus3 services. More information about how the groundwater product is estimated can be found here. G3P is a 3 years-long project, and 2022 is the 3rd and last year.
The WWQA represents a voluntary and flexible global multi-stakeholders network coordinated by UN Environment that advocates the central role of freshwater quality in achieving prosperity and sustainability. One of the three main activities of the Alliance is to produce a global assessment of freshwater quality (including groundwater) drawing on science – technology – innovation, including a data fusion approach combining in-situ monitoring, modelling and remote sensing.
Details about the G3P project and related tasks
The G3P project is divided in 5 work packages (WP). WP1 carries out the management of the project, while the quantification of TWS and the storage compartments (i.e. glaciers, snow, soil moisture, and surface water bodies) occurs during WP2 and WP3, respectively. The subtraction process happens within WP4, where the newly calculated groundwater product is evaluated against in-situ observations as well. Lastly, WP5 is the one dealing with dissemination of results, exploitation and use cases. IGRAC is leading WP5 and contributing to WP4.
The researcher will be involved in IGRAC’s contribution to WP4, the main task being to evaluate the satellite-based groundwater product produced in WP4 against in-situ observations of groundwater levels. Time series of groundwater levels from selected aquifers have been already collected and processed, and in some cases, groundwater storage change was calculated as well using these in-situ data and other hydrogeological data, such as specific yield. The researcher will have to determine how the gravity-based and terrestrial data relate to each other, and how meaningful is a comparison between them. Other tasks might include for instance to draw conclusions on observed behaviours or trends of G3P, and relate them to existing knowledge on groundwater resources around the world.
Details about the global groundwater quality project and related tasks
The assessment of global groundwater quality is a complex project, even more than the same endeavour for surface water, due to its hidden nature, three-dimensional distribution and long residence times, among others. In addition, knowledge and information necessary to produce a global groundwater quality assessment are highly dispersed. Finding answers to important questions as: “which contaminants are the most important and where are they found? Which places in the world need more attention and/or resources?” is a lengthy and complex process.
There is currently no guidance on how to produce a national or regional groundwater quality assessment based on point measurements, i.e. upscaling of local findings. How representative is the assessment of groundwater quality at the measurement point for a wider area around the point? What should be taken in account while making assumptions (and later decisions) on regional groundwater quality based on set of point measurements?
The researcher will support investigation on the ways groundwater quality is currently assessed at the regional scale in order to come up with a set of recommendation or guidelines to support this process. Special attention will be to aggregation of local measurements for the purpose of a regional assessment. Experiences and practices in upscaling/aggregation of groundwater quality findings will be collected and analysed. This may also include an analysis of the advantages and limitations of statistical methods, modelling, “use cases”, remote sensing, citizen science, etc.
For both projects, other activities include report writing, being involved in subsequent published papers, and working in close collaboration with the projects manager at IGRAC. In addition, the researcher might participate in preparation and implementation of other IGRAC core activities and external projects, including assessment, monitoring and management of global groundwater resources.
Education and skills
- Master's degree in hydrogeology, hydrology, civil engineering, environmental engineering, water resource engineering or related environmental science area with knowledge of (geo)statistics and data analysis.
- Skilled GIS (ArcGIS and/or QGIS) user.
- Knowledge of a programming language (e.g. python, R, Visual Basic).
- Fluency in oral and written English.
Work experience will be considered as advantageous for a junior position. Candidates with a several years of work experience will be considered for an intermediate position.
Applications, including a letter of motivation and CV should be sent to IGRAC by e-mail to Elisabeth Lictevout at email@example.com no later than 15-02-2022.
Please note that a similar position was advertised last year (to contribute to the G3P project), but it was not filled due to unexpected circumstances. If you applied last year, we encourage you to reapply.
1 GRACE was a satellite mission (2002-2017) to measure the Earth’s gravity field and its variation in space and time. It consisted of two satellites following each other on the same orbital track. At an orbital altitude of about 450 km, the distance between the two GRACE satellites was on average 220 km, but constantly changing due to the varying attraction of masses on the surface and inside the Earth. Repeated observations by this constellation ultimately yield changes in the mass distribution, such as changes in the distribution of water stored on and below the Earth's surface. https://www.nasa.gov/mission_pages/Grace/index.html;
2 GRACE Follow-On (GRACE-FO) has been launched into its Earth orbit in 2018 and provides continuity for the GRACE data set. https://gracefo.jpl.nasa.gov/; and
3 Copernicus is the European Union's Earth Observation Programme that offers information services based on satellite Earth Observation and in-situ data. https://www.copernicus.eu/en/copernicus-services.