Warmist Michael Mann says there is no need for statistics: ‘We can see climate change…now, playing on our TV screens’
Tax viruses!? Ocean viruses may have impact on Earth’s climate – ‘Could be responsible for billions of metric tons of extra CO2 every year’
Nature Geoscience. doi:10.1038/ngeo2766
Authors: Nathaniel L. Bindoff & William R. Hobbs
Circumpolar upwelling circulation near the Antarctic has mainly been attributed to winds. An analysis of water-mass transformation shows that the dominant driver is instead the formation of sea ice near Antarctica and its melt offshore.
Nature Geoscience. doi:10.1038/ngeo2746
Author: Mladen R. Nedimović
At mid-ocean ridges, the directions in which plates spread and the underlying mantle flows were thought to broadly align. A synthesis of results from ridges that spread at a variety of rates reveals that instead there may be a systematic skew.
Nature Geoscience. doi:10.1038/ngeo2749
Authors: Ryan P. Abernathey, Ivana Cerovecki, Paul R. Holland, Emily Newsom, Matt Mazloff & Lynne D. Talley
Ocean overturning circulation requires a continuous thermodynamic transformation of the buoyancy of seawater. The steeply sloping isopycnals of the Southern Ocean provide a pathway for Circumpolar Deep Water to upwell from mid depth without strong diapycnal mixing, where it is transformed directly by surface fluxes of heat and freshwater and splits into an upper and lower branch. While brine rejection from sea ice is thought to contribute to the lower branch, the role of sea ice in the upper branch is less well understood, partly due to a paucity of observations of sea-ice thickness and transport. Here we quantify the sea-ice freshwater flux using the Southern Ocean State Estimate, a state-of-the-art data assimilation that incorporates millions of ocean and ice observations. We then use the water-mass transformation framework to compare the relative roles of atmospheric, sea-ice, and glacial freshwater fluxes, heat fluxes, and upper-ocean mixing in transforming buoyancy within the upper branch. We find that sea ice is a dominant term, with differential brine rejection and ice melt transforming upwelled Circumpolar Deep Water at a rate of ∼22 × 106 m3 s−1. These results imply a prominent role for Antarctic sea ice in the upper branch and suggest that residual overturning and wind-driven sea-ice transport are tightly coupled.
Nature Geoscience. doi:10.1038/ngeo2745
Authors: Brandon P. VanderBeek, Douglas R. Toomey, Emilie E. E. Hooft & William S. D. Wilcock