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Author Spotlight: Unveiling Plankton Response to Climate Change Through Time-Series Data and Artistic Expression
Published on: July 28, 2023
Ocean freshening near the end of the Mesozoic
Wiesława Radmacher1, Igor Niezgodzki2, Vicente Gilabert3,4
1ING PAN - Institute of Geological Sciences, Polish Academy of Sciences, Research Center in Kraków, Senacka 1, Poland. ndkrol@cyf-kr.edu.pl.
Abstract:
Paleogeographic changes have significantly shaped ocean circulation and climate dynamics throughout Earth's history. This study integrates geological proxies with climate simulations to assess how ocean gateway evolution influenced ocean salinity near the end of the Mesozoic (~66 Ma). Our modeling results demonstrate that 1) Central American Seaway shoaling reorganizes ocean currents, and 2) Arctic marine gateway restrictions, confining Arctic-Global Ocean exchange exclusively to the Greenland-Norwegian Seaway, drive Arctic Ocean surface freshening and southward outflow of buoyant, low-salinity waters. However, only the combined effect of these two factors leads to both Arctic freshening and increased water mass stratification in the Greenland-Norwegian Seaway, proto-North Atlantic, and the Western Tethys. This scenario aligns with Maastrichtian palynological, micropaleontological, and geochemical records from high- and low-latitude sites. Our findings highlight the profound impact of these latest Cretaceous paleogeographic reconfigurations in altering global salinity patterns, underscoring their role as key drivers of global climate dynamics.
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