3D municipal model for administration and handling of water in large cities
With growing interest in using the subsurface for stormwater infiltration and other climate-related solutions or for heat-storage systems, groundwater cooling, water extrac
tion or for infrastructure such as tunnels and buildings, there is a strong demand for knowledge about the subsurface below our cities.
In 2015, GEUS finalised a project to develop a 3D geological/hydrogeological model of the subsurface under Odense Municipality. The project was carried out with Odense Municipality, VandCenter Syd, I-GIS and Alectia A/S with support from the Foundation for Development of Technology in the Danish Water Sector. The project worked intensively to couple the model of the natural geology of the deeper layers with the model of the surface layers which includes large man-made infill areas.
The model and the modelling tools developed are important for Odense Municipality and Vandcenter Syd related to manage and handle water. This includes tasks related to infiltration and diversion of water to reduce the risk of flooding or related to protecting drinking water supply. The project also produced a number of recommendations
for developing 3D geological/hydrogeological models below the city which may serve as inspiration to others.
Faster meltwater release from the Greenland ice sheet
In 2015, Nature Climate Change published the results of a study by glaciologists from GEUS and the Cooperative Institute for Research in Environmental Sciences (CIRES) in Boulder, USA. The results revealed that meltwater from the Greenland ice sheet may be released faster than expected because of massive ice layers in the surface-near layers of snow and firn. Researchers have examined the effect of the very high temperatures observed in recent years on the structure of the surface-near layers of snow and ice, called firn, in the ice sheet near Kangerlussuaq in West Greenland. During the three expeditions in 2012, 2013 and 2015, researchers examined several hundred kilometres of the ice-sheet surface, mapping the structure in the firn layers with radar equipment and by drilling numerous firn cores. The studies showed that large quantities of meltwater have infiltrated the snow and firn during the very warm periods observed in recent years. The meltwater freezes again and forms massive ice layers which function as a lid, preventing infiltration of additional water. The meltwater therefore does not seep down into the firn, but is led away from the ice in streams along the surface of the ice. Researchers first discovered this phenomenon in 2012, when large rivers of meltwater suddenly formed on the surface of the ice in areas where the water had previously remained in the firn, where it refroze. The 2015 studies received financial support from the Danish Council for Independent Research (Natural Sciences).
Mapping the sea ice and marine primary production
Arctic sea ice has been dwindling over the past decades. This affects marine primary producers such as diatoms and bluegreen algae, which are the basis for the marine ecosystem in the Arctic, and this, in turn, has repercussions for marine food
chains, the carbon cycle and the fishing industry. In April and May, researchers from GEUS gathered sediment cores from the sea floor under the frozen Wandel Sea at Station Nord in NorthEast Green land to reconstruct long-term changes in the marine primary production caused by changes in sea-ice cover. Sediment cores from the sea floor contain information about climate and environment conditions going back thousands of years, and important parameters such as temperature, salinity, sea-ice cover and productiv ity can be reconstructed using a combination of geochemical, sedimentological and micropalaeontological indicators. The new data will make it possible to develop more reliable forecasts of developments in the Arctic using sea-ice and eco-system models. The project is financed by the VILLUM FONDEN Young Investigator Programme and the fieldwork was organised by the Arctic Science Partnership jointly with the Arctic Research Center at Aarhus University.
Robustness to flooding
GEUS is taking part in a common Nordic research project, NORDRESS, which is generating knowledge about how to better protect society against natural disasters and how best to secure and help society recover after a disaster event. Recent years extensive flooding in Denmark as a consequence of cloudbursts etc. have demonstrated a need for this type of knowledge. GEUS is heading efforts to develop monitoring systems which can give early warning and information about the extent of a flood event through public and stakeholder involvement. Researchers are drawing on experience from a previous GEUS pilot project, which examined the possibilities for real-time warning with GEUS' national hydrological model, so that the model can continuously calculate developments in the surface water and groundwater throughout Denmark. Part of this work involved a user survey among municipalities, water utility companies, farmers and other stakeholders to identify the types of hydrological data in demand and the format in which to deliver them.
The NORDRESS project involves developing methods for how to utilise the real-time experiences of the public before, during and after a flood event, so that these experiences can be included in a real-time warning system or help in mapping the extent of flood events and prioritising response measures. For example, this could be through photos or reports submitted directly by individuals via apps and the social media. NORDRESS is receiving funding from Finland, Iceland, Norway, Sweden and NordForsk