Recent seafloor exploration has shown that volcanic-hosted massive sulfides (VHMS) occur in modern silicic calderas formed by highly explosive eruptions at substantial water depths. Sampling of these has so far been restricted to surficial deposits. Ancient analogs provide a time-integrated view of the structure and fill of deepwater calderas, but constraints on paleo-water depths have previous...

Lateglacial (19.0–11.7 ka ago) paleo-temperature records in the Western European Alps document several short-term cooling episodes within general post-Last Glacial Maximum warming trend, phase with North Hemisphere climatic oscillations. Alpine paleo-precipitation reconstructions are instead rare, and further constraints needed order to assess whether cold periods were associated a modified atm...

Abstract. Heat is a naturally occurring, widespread groundwater tracer that can be used to identify flow patterns in systems. Temperature measurements, being relatively inexpensive and effortless gather, represent valuable source of information which exploited reduce uncertainties on flow, and, for example, support performance assessment studies waste disposal sites. In lowland setting, however...

Earth system climate sensitivity (ESS) is the long-term (>10³ year) response of global surface temperature to doubled CO₂ that integrates fast and slow climate feedbacks. ESS has energy policy implications because global temperatures are not expected to decline appreciably for at least 10³ year, even if anthropogenic greenhouse gas emissions drop to zero. We report provisional ESS estimates of ...

Uranium isotopes have been used as mechanistic or time scale tracers of natural processes. This paper describes the occurrence and redistribution of U in the Vendian aquifer of a paleo-valley in NW Russia. Forty-four rock samples were collected from nine boreholes with depths up to 160 m, and 25 groundwater samples were collected from 23 boreholes with depths up to 300 m. The U, Fe concentratio...

[1] Understanding the mechanisms governing temporal variability of ice stream flow remains one of the major barriers to developing accurate models of ice sheet dynamics and ice-climate interactions. Here we analyze a simple model of ice stream hydrology coupled to ice flow dynamics and including drainage and basal cooling processes. Analytic and numerical results from this model indicate that t...

Species assemblage in a local community is determined by the interplay of evolutionary and ecological processes. The Tropical Niche Conservatism hypothesis proposes mechanisms underlying patterns of biodiversity in biological communities along environmental gradients. This hypothesis predicts that, among other things, clades in areas with warm or wet environments are, on average, older than tho...