Main TWP2 results

TWP2 Toward integrated modelling of the Mediterranean systems

Ecosystem and climate modelling

For land ecosystems, considerable progress with respect to OT-Med objectives has been made through the work of a PhD student (S Decock) and a post-doc (M Fader) working on the agroecosystem model LPJmL (Fader et al. 2014). One post-doc has been developing the Mediterranean Sea biogeochemical/physical model ECO3M (Alekseenko et al. 2014). The LOVECLIM climate model (of intermediate complexity) has been obtained from H. Goosse (Louvain-la-Neuve) and our modelling engineer has been trained to work on it. Gea-Izquierdo et al. (2015) extended an existing mechanistic model to analyse photosynthesis and variability in carbon allocation in two evergreen species in two Mediterranean forests. The proposed model has a great potential with using abundant dendrochronological data and to analyse forest performance under climate change. This would help to understand how different interfering environmental factors produce instability in the climatic signal expressed in tree-rings.

Approaching the integrated model

To better coordinate the activities mentioned above, and to develop a common framework, a first dedicated OT-Med modelling workshop was held in June 2013. It provided an overview of the different modelling activities in the partner laboratories of OT-Med, and significantly broadened the discussion about model integration. Follow-up discussions have taken place at both annual meetings. At the present stage, OT-Med now develops concrete initiatives for near-term model coupling, notably between land and ocean ecosystem models.

The future plan in this domain consists in developing an integrated process-based model of the key elements of the coupled system: the dynamics of agro-ecosystems under different management scenarios, and the dynamics of the first levels of the marine food web (from nutrients to jellyfishes) driven by ocean physics and rivers nutrients inputs from the land model. The interaction between land and sea primarily concerns the flow of nutrients which is significantly affected by management decisions on land and which has a notable impact on the marine ecosystem and the services it provides. In addition, in a common framework, options for enhanced management of the Mediterranean region will be assessed, and the consequences of environmental change for socio-economic vulnerability will be estimated.

References

  • Alekseenko E, Raybaud V, Espinasse B, Carlotti F, Queguiner B, Thouvenin B, Garreau P, Baklouti M 2014 Seasonal dynamics and stoichiometry of the planktonic community in the NW Mediterranean Sea: a 3D modeling approach Ocean Dynamics 64(2):179-207
  • Fader M, Bondeau A, Cramer W, Decock S, Shi S 2014 How much water do we need for irrigation under climate change in the Mediterranean? Geophysical Research Abstracts 16, EGU2014-13848
  • Gea-Izquierdo G, Guibal F, Joffre R, Ourcival JM, Simioni G, Guiot J 2015 Modelling the climatic drivers determining photosynthesis and carbon allocation in evergreen Mediterranean forests using multiproxy long time series. Biogeosciences Discuss 12:1-42, http://www.biogeosciences.net/12/36..., doi: 10.5194/bgd-12-1-2015
  • Fader M, von Bloh W, Shi S, Bondeau A, Cramer W (2015) Modelling Mediterranean agro-ecosystems by including agricultural trees in the LPJmL model. Geosci Model Dev, 8, 3545–61. doi: 10.5194/gmd-8-3545-2015
  • Fader M, Shi S, von Bloh W, Bondeau A, Cramer W (2015) Mediterranean irrigation under climate change: more efficient irrigation needed to compensate increases in irrigation water requirements. Hydrol Earth Syst Sci Discuss, 12, 8459–504. doi: 10.5194/hessd-12-8459-2015