Modeling for the Hann Bay depollution project
The Senegalese National Water Office (ONAS) has been in charge to implement the Greater Dakar sanitation plan: to collect, treat and disperse the industrial and domestic wastewater generated by the country’s capital. The technical solutions chosen resemble those preferred in developed countries: the high costs of water treatment lead to the use of the coastal ocean to dilute the residual pollutants and contaminants.
In 2013-2014, we have assisted our historical partner, the Laboratory of Physics of the Atmosphere and the Ocean, to conduct a complementary study on the discharge point of Mbao. Through modelling studies, we did confirm the significant amelioration of nearshore water qualities to be expected, even with an outfall of only 2 km length.
UPSEN-UPSEN2-ECOAO-AWA field experiments
The data from these field campaigns with mutidisciplinary objectives (physical and planktonic ecosystem for upsen2, planktonic ecosystem and small pelagic fish for ecoao) have led to significant advances (and are still being processed).
Specifically, they have led to new insight into:
- the local oceanic circulation, turbulence and internal wave field and their role in transporting heat, salt, and biogeochemical properties (Capet et al, 2017)
- the occurence of short-term deoxygenation episodes (Machu et al, 2018). The subject has also been studied using in situ measurements made at fixed mooring MELAX (Tall et al, 2021)
- the preferential role of the Dakar bay (“Baie de Hann”) as a reproduction hotspot for small pelagic fish (Ndoye et al, 2017)
- the distribution of zooplankton over the southern senegalese shelf from acoustic sampling (Diogoul et al, 2020)
Anticipating changes in ocean physics at the 2080-2100 horizon
As part of the AMMA2050 project (SCUS 2050 component, 2017-2019), SOLAB partners in Senegal and France have analysed CMIP5 simulations to shed light on possible physical changes in the WA coastal ocean at the 2080-2100 time horizon. We found robust but modest decrease in upwelling wind intensity in the southern part of the region (typically Senegal) and limited changes further north (Sylla et al, 2018). Downscaling of CMIP5 wind regime changes onto the Senegalese sector confirms that modifications of the circulation will be limited (Ndoye et al, in preparation). This places focus on temperature changes and how they will impact the ecosystem/food chain.
Capacity building/local scientist training
In addition to Pr. Bamol Sow, SOLAB can rely on several local experts trained thanks to the joint international laboratory ECLAIR1-2 (2012 to present): Siny Ndoye, Andul-Wahab Tall, Khassoum Correa, Youssouph Coly, Aida Beye, Ibrahima Camara, Lala Kounta, Saliou Faye, and Baye Cheikh Mbaye.