Publications by authors named "Erin Pettit"

Knowledge gaps about how the ocean melts Antarctica's ice shelves, borne from a lack of observations, lead to large uncertainties in sea level predictions. Using high-resolution maps of the underside of Dotson Ice Shelf, West Antarctica, we reveal the imprint that ice shelf basal melting leaves on the ice. Convection and intermittent warm water intrusions form widespread terraced features through slow melting in quiescent areas, while shear-driven turbulence rapidly melts smooth, eroded topographies in outflow areas, as well as enigmatic teardrop-shaped indentations that result from boundary-layer flow rotation.

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Article Synopsis
  • Feedback loops between ice melt, glacier flow, and ocean circulation can significantly speed up ice loss at tidewater glaciers, impacting sea-level rise predictions.
  • Current models of ice melt underestimate melting rates by not accounting for air bubbles trapped in glacier ice, which can lead to errors of 10-100 times compared to actual observations.
  • Laboratory experiments reveal that the bursting of these pressurized bubbles enhances ice melt by introducing buoyancy and turbulence, suggesting that glaciers melt 2.25 times faster than bubble-free ice and improving the accuracy of global sea-level rise forecasts.
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West Antarctic ice-shelf thinning is primarily caused by ocean-driven basal melting. Here we assess ocean variability below Thwaites Eastern Ice Shelf (TEIS) and reveal the importance of local ocean circulation and sea-ice. Measurements obtained from two sub-ice-shelf moorings, spanning January 2020 to March 2021, show warming of the ice-shelf cavity and an increase in meltwater fraction of the upper sub-ice layer.

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Antarctic subglacial environments host microbial ecosystems and are proving to be geochemically and biologically diverse. The Taylor Glacier, Antarctica, periodically expels iron-rich brine through a conduit sourced from a deep subglacial aquifer, creating a dramatic red surface feature known as Blood Falls. We used Illumina MiSeq sequencing to describe the core microbiome of this subglacial brine and identified previously undetected but abundant groups including the candidate bacterial phylum Atribacteria and archaeal phylum Pacearchaeota.

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The objective of the study is to assess the impact of emergency department (ED) intimate partner violence (IPV) counseling and resource referrals on patient-perceived safety and safety planning. ED patients with risk factors were offered consultation with trained IPV advocacy counselors who completed safety assessments, provided resource referrals, and helped patients develop safety plans. Patients were contacted after ED intervention to assess progress and further assist in IPV counseling.

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