by Laurent Lebreton et al., June 7, 2017 in Nature Communication
Plastics in the marine environment have become a major concern because of their persistence at sea, and adverse consequences to marine life and potentially human health. Implementing mitigation strategies requires an understanding and quantification of marine plastic sources, taking spatial and temporal variability into account. Here we present a global model of plastic inputs from rivers into oceans based on waste management, population density and hydrological information.
by Michael Stars et al., June 5, 2017 in Nature Communication
High latitude ocean gateway changes are thought to play a key role in Cenozoic climate evolution. However, the underlying ocean dynamics are poorly understood. Here we use a fully coupled atmosphere-ocean model to investigate the effect of ocean gateway formation that is associated with the subsidence of the Greenland–Scotland Ridge. We find a threshold in sill depth (∼50 m) that is linked to the influence of wind mixing.
by Hiroki Tokinaga et al., PNAS, May 1, 2017
Arctic amplification is a robust feature of climate response to global warming, with large impacts on ecosystems and societies. A long-standing mystery is that a pronounced Arctic warming occurred during the early 20th century when the rate of interdecadal change in radiative forcing was much weaker than at present. Here, using observations and model experiments, we show that the combined effect of internally generated Pacific and Atlantic interdecadal variabilities intensified the Arctic land warming in the early 20th century.
by University of California – Davis, May 16,2017 in ScienceDaily
Chronicling Earth’s past temperature swings is a basic part of understanding climate change. One of the best records of past ocean temperatures can be found in the shells of marine creatures called foraminifera
by JoNova (blog), May 2017
Welcome to paleolithic politics: in this version, the witchdoctors are syndicated and with lap tops.
by Yair Rosenthal et al., January 1, 2017
Here we review proxy records of intermediate water temperatures from sediment cores in the equatorial Pacific and northeastern Atlantic Oceans, spanning 10,000 years beyond the instrumental record.
These records suggests that intermediate waters were 1.5–2 °C warmer during the Holocene Thermal Maximum than in the last century.
Intermediate water masses cooled by 0.9 °C from the Medieval Climate Anomaly to the Little Ice Age.
by Tim De Vries et al., Nature Feb 9, 2017
Continued weakening of the upper-ocean overturning is likely to strengthen the CO2 sink in the near future by trapping natural CO2 in the deep ocean, but ultimately may limit oceanic uptake of anthropogenic CO2.
by J. Lecomte et al., CNRS, December 16, 2013
The natural increase in solar luminosity — a very slow process unrelated to current climate warming — will cause the Earth’s temperatures to rise over the next few hundred million years. This will result in the complete evaporation of the oceans. The first three-dimensional climate model able to simulate the phenomenon predicts that liquid water will disappear on Earth in approximately one billion years, extending previous estimates by several hundred million years.
Jérémy Leconte, Francois Forget, Benjamin Charnay, Robin Wordsworth, Alizée Pottier. Increased insolation threshold for runaway greenhouse processes on Earth-like planets. Nature, 2013; 504 (7479): 268 DOI: 10.1038/nature12827
par D. Swingedouw et al., CNRS, 15 février 2017
Dans le cadre du projet européen EMBRACE, une équipe d’océanographes a réexaminé ces 40 projections climatiques en se focalisant sur un point névralgique au nord-ouest de l’Atlantique Nord : la mer du Labrador. Cette mer est le siège d’un phénomène de convection, qui nourrit à plus grande échelle la circulation océanique de retournement. Ses eaux de surface se refroidissent fortement en hiver, deviennent plus denses que les eaux de profondeur et plongent vers le fond. La chaleur des eaux profondes est transférée vers la surface et empêche la formation de banquise
Mark Imisides, December 07, 2009
Carbon dioxide, we are told, traps heat that has been irradiated by the oceans, and this warms the oceans and melts the polar ice caps. While this seems a plausible proposition at first glance, when one actually examines it closely a major flaw emerges.