Volume 13 Issue 9, September 2020

It is commonly thought that old groundwater cannot be pumped sustainably, and that recently recharged groundwater is inherently sustainable. We argue that both old and young groundwaters can be used in physically sustainable or unsustainable ways.

Deep, carbon-rich Pacific waters intruded into the South Atlantic some 38 to 28 thousand years ago. This deep Pacific expansion could have represented a considerable sink of atmospheric CO₂, one that helped initiate the Last Glacial Maximum.

Deliberate application of sulfur onto croplands as fertilizer and pesticide probably causes environmental damage similar to historical acid rain events, according to a literature review and four case studies from the United States.

Mounds within Ceres’s Occator crater may have formed by freezing of water-rich impact-induced melt, by a process analogous to that of pingo formation on Earth, according to an analysis of data from NASA’s Dawn mission.

Experiments show that the iron isotopic composition of iron meteorites can be explained by core crystallization, and suggest the presence of sulfur-rich core material that remains unsampled by meteorite collections.

Meltwater entering the Southern Ocean from Antarctic ice shelves varies substantially from year to year, with consequences for Southern Ocean circulation and climate, according to remote sensing estimates of ice-shelf basal melting rates.

A global map of rock-debris cover on mountain glaciers shows its spatial distribution and evolution.

Carbon-rich Pacific deep water extended into the South Atlantic some 38,000 to 28,000 years ago, potentially contributing to a reduction in atmospheric carbon dioxide and the onset of the Last Glacial Maximum, according to deep-water carbonate chemistry reconstructions.

Antarctic ice volume expansion in the middle Miocene coincides with Southern Ocean cooling, according to biomarker and clumped isotope temperature records from south of Tasmania.

Phosphorus remobilized from seafloor sediments due to a reduced influx of iron-oxide from land led to widespread anoxia during the end-Permian mass extinction, according to palaeoredox and phosphorus speciation proxy records from Svalbard.

In one earthquake, an oceanic transform fault ruptured in one direction and then backwards at a speed exceeding that of shear-wave propagation, according to an analysis of data recorded by nearby seafloor and global seismometers.