INDEXCLIMA · Indian-Atlantic interocean exchange as modulator of global climate
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2019-10-01 → 2021-09-30
- EU contribution
- €184,708
- Participants
- 1
- Scheme
- MSCA-IF-EF-ST
Lines connect the coordinator with its partners.
Results in brief
Indian-Atlantic interocean exchange as modulator of global climate
The INDEXCLIMA project (Indian-Atlantic interocean exchange as modulator of global climate) investigated the relationship between Atlantic deep water entering the Indian Ocean and Indian surface water flowing into the Atlantic Ocean over the last 630,000 years. The warm and salty surface Indian waters are transported into the Atlantic Ocean through the so-called Agulhas rings. These dense rings may contribute to maintain the strength of global thermohaline circulation, including the Gulf Stream that keeps a temperate climate in Europe. The circulation state affects the ocean capacity to sequestrate atmospheric CO2. The study period covers different glacials-interglacials characterised by distinct climate conditions. Even if the project results will attract attention of mainly scientists working on Earth and Climate Sciences, the carbon cycle and climate regulation by a large-scale oceanic circulation are of great interest of the society. In short, the project contributes to better understanding the interaction between Ocean and Climate by a unique approach reconstructing both surface and deep water variabilities from the same archives using geochemical proxies with microfossil assemblage. The overall objectives of the project were: (1) To reconstruct how the Atlantic deep water and southern-sourced deep water flowing into the Indian Ocean varied during the last 630,000 years, and evaluate how deep-water carbon storage varied with time and space. (2) To analyse the relationship of Indian-Atlantic interocean exchange between surface and deep waters in order to evaluate the impact of the Indian surface waters entering Atlantic Ocean via the Agulhas rings to the Atlantic meridional overturning circulation under different climate conditions.
Data: CORDIS, © European Union
Project objective
Indian-Atlantic interocean exchange (IAIE), occurring through Agulhas current/leakage, is one of the return flows of global thermohaline circulation that contributes to the temperate climate in Europe. Since IAIE affects the transport of heat and salt to the zone of deep water formation, the variability of Atlantic Meridional Overturning Circulation (AMOC) is related to IAIE as shown by instrumental observation and past reconstructions. However, the relationship between the IAIE and AMOC under different climate conditions including distinct atmospheric CO2 concentration is still to be elusive. The INDEXCLIMA (INDian-Atlantic interocean EXchange as modulator of global CLIMAte) project aims to study the deep-water IAIE, Agulhas current/leakage and AMOC evolution over the last 1000 kyr when internal feedback processes have modified climatic cyclicity from 41 kyr to 100 kyr (Mid-Pleistocene transition) and enhanced the amplitude of interglacial periods (Mid-Brunhes event ca. 430 kyr). The study area is the Mozambique Channel (Indian Ocean) and the Cape Basin (SE Atlantic Ocean) where 3 marine sediment cores were drilled and are available at CEREGE, France. The originality of this project resides on the reconstruction of deep water masses (Nd isotopic compositions, benthic foraminifera) and of surface Agulhas current (planktonic foraminifera) from the same cores across an Indian-Atlantic transect. This will allow estimating lead and lag between Agulhas current/leakage and deep water circulation changes. The study period beyond 800 kyr is also in line with the next target of glaciological community. This project is a great opportunity for me to develop new geochemical and technical skills including mastering Nd isotope geochemistry, the application of an innovative instrument that automatically sort foraminiferal tests and a new software for foraminiferal classification. These new skills will complement my previous knowledge improving my career possibilities in academia.
Original text from CORDIS.
Participants
- CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS · ParisCoordinatorFrance
Links
Data: CORDIS, © European Union