Climatic & environmental changes

Climatic and environmental changes and their impacts on hydrology: changes that can happen in the rivers hydrological regimes are important elements for water resources managers. They can be linked to climatic or environmental changes.

Environmental changes and trend detections

Paired catchments: basins that have a high similarity degree. Reference for impact studies on vegetation cover for the hydrology of small basins (V. Andréassian)

To analyse the change of hydrological behaviour of catchments (link between rainfall and streamflow), we can use rainfall-runoff models, which allows characterizing the functioning of the basin for several periods.

Works on trend detections were lead by Nascimento (1995), and then by Andréassian (2002), who studied the link between the change of hydrological behaviour and evolution of the forest cover.

Climate change and impacts

It is now very likely, as the IPCC reports indicate, that the climate of next decades will be different from the current climate. This climate change will have an impact on hydrology at local or more global scales, because of the precipitation or temperature modifications, as well as demographic or socio-economic modifications.

That is why we work on the diverse problematics linked to climate change and hydrology. The knowledge of climate change and its consequences is still impacted by several uncertainties related to:

  • climate and socio-economic scenarios used,
  • climate models used,
  • methods used to adapt the climate predictions to the scale of hydrological models,
  • to the hydrological modelling used and their robustness under future conditions.

With other teams from Irstea (HYCAR, RiverLy, G-Eau, RECOVER, etc.) we are interested in the following questions:

  • how to quantify the relative part of the diverse uncertainties sources?
  • how to reduce the effects of climate change?
  • which impact on hydrology and water-related policies?
  • what are our adaptation capacities and what are our future needs?

The question of the relevance of using hydrological models calibrated on current conditions, for future periods that will be different, is also one of our research areas:

Several national or international projects, in collaboration with numerous research institutes and water resources companies, are the basis for our researches in this area: RExHySS, Explore2070, Rheinblick2050, Climaware, R2D2, Imagine2030, Climsec, Hydroqual, MOSARH21, CHIMERE21 projects.

For more information: see our publications.