How is salinity impacting the formation of sub-surface waters (known as Mode Waters) in the South-West Pacific Ocean?

Audrey Hasson is a researcher in physical oceanography. She specializes in the study of water bodies based on satellite measurements. After two years at the Jet Propulsion Laboratory (Caltech/NASA), and 2 years as a fellow at the Centre National des Etudes Spatiales Français (CNES), Audrey is an ESA Living Planet post-doctoral fellow. She currently works at LOCEAN, the oceanography laboratory of the Pierre-Simon Laplace Institute (IPSL). 

Her latest work focused on understanding the ocean surface salinity variability using European and American satellites, as well as in situ observations and numerical simulations. These studies eventually provide a better knowledge of changes in the hydrological cycle in the context of the El Niño phenomenon. Audrey regularly participates in international conferences and campaigns at sea in the tropical Pacific and Antarctica.

Beyond this scientific work, Audrey is involved in scientific communication by leading a project to popularize science among a blind and visually impaired public, in partnership with the association “Les Etoiles Brillent pour Tous”. Audrey is also a laureate of the UNESCO/L’Oréal foundation Award and is an ambassador for the association “Pour les Filles et la Science” and regularly intervenes in schools to raise awareness of STEM among young girls. 

Research objectives

1. Enhance our knowledge of the role of surface salinity in the formation of Mode Waters (MW)s and of the processes behind the variability of surface salinity in formation areas.
2. Characterise the relationship between the surface and subsurface salinity signals along the MWs pathways
3. Determine the pathways of the MWs and the time need for them to reach the equatorial mixed layers
4. Establish the proportion of signal that reaches the mixed layer and its effect on the mixed layer characteristics
5. Characterise the role of the MWs variability in volume and density in the Sea Level variability at the interannual to longer timescales.

Read more on the research project sheet. 

Publications

Boutin, J., Vergely, J.-L., Marchand, S., D’Amico, F., Hasson, A., Kolodziejczyk, N., et al. (2018). New SMOS Sea Surface Salinity with reduced systematic errors and improved variability. Remote Sensing of Environment,Volume 214,2018,Pages 115-134,ISSN 0034-4257. https://doi.org/10.1016/j.rse.2018.05.022

Dassié, E. P., Hasson, A., Khodri, M., Lebas, N., & Linsley, B. K. (2018). Spatiotemporal Variability of the South Pacific Convergence Zone Fresh Pool Eastern Front from Coral-Derived Surface Salinity Data. Journal of Climate, 31(8), 3265–3288. https://doi.org/10.1175/JCLI-D-17-0071.1

Hasson, Delcroix, T., & Dussin, R. (2013). An assessment of the mixed layer salinity budget in the tropical Pacific Ocean. Observations and modelling (1990-2009). Ocean Dynamics, 63(2–3), 179–194. https://doi.org/10.1007/s10236-013-0596-2

Hasson, A., Delcroix, T., & Boutin, J. (2013). Formation and variability of the South Pacific Sea Surface Salinity maximum in recent decades. Journal of Geophysical Research-Oceans, 118(10), 5109–5116. https://doi.org/10.1002/jgrc.20367

Hasson, A. E. A., Mills, G. A., Timbal, B., & Walsh, K. (2009). Assessing the impact of climate change on extreme fire weather events over southeastern Australia. Climate Research, 39(2), 159–172. https://doi.org/10.3354/cr00817

Hasson, Audrey, Koch-Larrouy, A., Morrow, R., Juza, M., & Penduff, T. (2012). The origin and fate of mode water in the southern Pacific Ocean. Ocean Dynamics, 62(3), 335–354. https://doi.org/10.1007/s10236-011-0507-3

Hasson, Audrey, Delcroix, T., Boutin, J., Dussin, R., & Ballabrera-Poy, J. (2014). Analyzing the 2010–2011 La Niña signature in the tropical Pacific sea surface salinity using in situ data, SMOS observations, and a numerical simulation. Journal of Geophysical Research: Oceans, 119(6), 3855–3867. https://doi.org/10.1002/2013JC009388

Hasson, Audrey, Puy, M., Boutin, J., Guilyardi, E., & Morrow, R. (2018). Northward Pathway Across the Tropical North Pacific Ocean Revealed by Surface Salinity: How do El Niño Anomalies Reach Hawaii? Journal of Geophysical Research: Oceans, 123(4), 2697–2715. https://doi.org/10.1002/2017JC013423

Hasson, Audrey, Farrar, J. T., Boutin, J., Bingham, F. M., & Lee, T. (2019). Intraseasonal variability of surface salinity in the eastern tropical Pacific associated with mesoscale eddies. Accepted at Journal of Geophysical Research: Oceans.

Li, J.-L. F., Wang, Y.-H., Lee, T., Waliser, D., Lee, W.-L., Yu, J.-Y., Hasson., A., et al. (2016). The impacts of precipitating cloud radiative effects on ocean surface evaporation, precipitation, and ocean salinity in coupled GCM simulations: OCEAN SALINITY IN GCM SIMULATIONS. Journal of Geophysical Research: Atmospheres, 121(16), 9474–9491. https://doi.org/10.1002/2016JD024911

Protat, A., Bouniol, D., Delanoe, J., May, P. T., Plana-Fattori, A., Hasson, A., et al. (2009). Assessment of Cloudsat Reflectivity Measurements and Ice Cloud Properties Using Ground-Based and Airborne Cloud Radar Observations. Journal of Atmospheric and Oceanic Technology, 26(9), 1717–1741. https://doi.org/10.1175/2009jtecha1246.1

Supply, A., Boutin, J., Vergely, J.-L., Martin, N., Hasson, A., Reverdin, G., et al. (2017). Precipitation estimates from SMOS sea-surface salinity: Precipitation Estimates from SMOS Sea-Surface Salinity. Quarterly Journal of the Royal Meteorological Society. https://doi.org/10.1002/qj.3110