Human impacted land-ocean continuum

Isabelle DADOU
isabelle.dadou@legos.obs-mip.fr
05 61 33 29 54

Maria-Angela BASSETTI
maria-angela.bassetti@univ-perp.fr
04 68 66 17 47

river • lake • estuary • river plume • coastal • ocean physics • biogeochemistry • sediment • human impact • climate change

The land-sea continuum includes all natural (continental, coastal and marine) and urban areas. It is an environment strongly impacted and weakened by human activity: understanding the interactions between the elements of the natural system and anthropic action is fundamental to follow its evolution under rapid environmental changes. In particular global warming and sea level rise are accelerating rapidly according to the latest IPCC report 2021-2022 (International Panel on Climate Change) with increases in extreme events in the land-sea continuum area.

The overall objective of this module is to introduce students to different multidisciplinary approaches to the study of this complex system subject to strong anthropic pressure and climate change using examples and applications involving complementary tools: in situ data, satellite and modeling.

It will be approached through two main blocks:

• Knowledge of the river-littoral-ocean continuum environment and its study: main processes of the river-littoral-ocean-atmosphere continuum (physical, biogeochemical) and main human/anthropic impacts, measurements and instruments (physical and biogeochemical). Accuracy, limitations, difficulty of use in this complex environment.

• Example and applications: in the Mediterranean Sea or other geographical areas subject to anthropogenic effects using in situ, satellite and modeling data.

None.

Main physical and chemical processes on this land-ocean continuum impacted by humans: tools and analyses via different applications/examples:

• Water continuum: river water (flow, etc.), watersheds, extent of flood areas, exchange along the continent – river – lagoon – coastal area – ocean; impact of coupling and feedback with the atmosphere (precipitation, etc.), anthropogenic effects and climate change, its variability and extreme events.

• Continuum of water level: river, coastal, ocean : its variability, extreme events with the combined effects of river discharge/tides/storms/waves/climate change, surge and flooding, salinization.

• Sediment and erosion continuum: natural and anthropogenic forcing on coastal dynamics and morphology: in particular,  study of coastal zone erosion and tools for its quantification, transport and accumulation of sediments at the land-sea interface: role in biochemical cycles (nutrient supply), carbon burial and rapid modifications of subaquatic morphology (dunes migration, mudbelts formation) 

• Continuum transport of chemical elements (nutrients, pollutants) from the river to the ocean – anthropic effects: productivity, eutrophication, anoxia, acidification, greenhouse gas emissions.