The WP2 Interface models-data aims to improve the use of observatories’ data in modeling and to promote data-models merging in order to enhance the knowledge on the Critical Zone’s functioning. The WP2 also aims at promoting, through modeling, dialogue and interactions between the OZCAR-RI’s teams.
A multi-site approach to modeling
A lot of modeling work has been carried out on the different sites of the OZCAR-RI which, combined with data analysis, has provided some key knowledge. However, these approaches remained very site-specific and often used different modeling tools.
In the context of the OZCAR-RI, it became necessary to use a multi-site modeling approach based on the data from observatories in order to foster a comparative approach and to try to answer “big” questions on the functioning, general and local, of the Critical Zone.
A first step was to identify the modeling tools used in OZCAR-RI and the type of observables needed/used. A synthesis was presented at the TERENO conference in October 2018 (Habets et al., https://www.ufz.de/tereno2018/index.php?en=44426).
Towards a better dialogue between observation data and models
In order to demonstrate the added value of a data-models fusion work on a set of OZCAR-RI’s observatories, a posdoctoral fellow, Sylvain Kuppel, was recruited mid 2019.
After a consultation with the teams interested by the approach, it was decided to implement the EcH2O-iso ecohydologic model on four observatories sharing a similar geology., but different climatic and land-use contexts : the Strengbach site in the Vosges (OHGE), the Kerbernez site in Brittany (AgrHys), the Ara site in Benin (AMMA-CATCH) and the Mule Hole site in India (M-TROPICS). This allowed the following scientific questions to be adressed :
- Where do plants extract the water they consume and how does this influence water pathwayss in the watershed?
- How do water flows and water residence times in the regolith (the soil’s altered area) affect the transport of major elements?
To address the second question, the EcH2O-ISO was linked with the WITCH3D chemical alteration model.