Ocean and climate Plateform

CNRS and Sorbonne Universités are members of the Ocean and Climate Plateform an alliance of non-governmental organizations, universities and research institutes, created with support from the UNESCO Intergovernmental Oceanographic Commission on the World Ocean Day in June, 8th 2015.

The Ocean and Climate Platform main goal is to integrate the ocean in the debate on climate, and contribute to successful negotiations for an ambitious agreement at the COP21.

As part of the Scientific Committee of OCP, the chair contributed to the writing of the published scientific factsheets dedicated to climate issues for the deep ocean.

 

The deep ocean: any climate issues?

The deep ocean (200m below the surface to 11,000m) represents over 98% of marine waters in volume. The image of a stable and homogeneous environment over vast areas, with low biological activity, does not actually reflect the diversity of deep-sea ecosystems nor their sensitivity to climate change. Even on the abyssal plains, variations in abundance of key species have been attributed to changes in the photosynthetic productivity at the surface of the ocean. Moreover, many biodiversity and productivity ‘hot-spots’ of the deep seafloor, and their foundation species such as deep-sea corals could be particularly vulnerable to the already observable changes at great depths, such as local or regional warming deep water, acidification and deoxygenation and modifications of the circulation of water masses. This vulnerability questions our ability to anticipate the consequences of climate change on poorly known ecosystems and the services they provide.