This manuscript presents a validation exercise for a proxy of deep water convection intensity. This exercise consisted in the integrated analysis of direct measurements of deep current intensities, with grain-size distribution analysis on sediment trap collected particles and on sediment cores. The results of this exercise have allowed to directly link a particular mode of coarse size particles to fast current speeds associated to deep convection events in the Gulf of Lion. After this proxy validation, its application in the sedimentary record has allowed, by the first time, to reconstruct changes in the deep convection intensity for the last 2000yr, indicating that the Roman and the late Medieval periods together with the early Little Ice Age recorded the strongest intensity in the formation of Western Mediterranean Deep Water Masses. These results have revealed that strong deep convection occurred during climatic periods of relatively warm but also cold conditions, pointing out to the evaporation-precipitation valance of the whole basin as a key factor controlling deep convection intensity.
Cisneros, M, Cacho, I., Frigola, J., Sanchez-Vidal, A., Calafat, A., Pedrosa-Pàmies, R., Rumín-Caparrós, A., Canals, M., (2019). Deep-water formation variability in the north-western Mediterranean Sea during the last 2500 yr: A proxy validation with present-day data. Global and Planetary Change 177, 56-68.
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