Radio-Echo Sounding Over Polar Ice Masses

Peer reviewedPublisher PD

Subglacial drainage processes at a High Arctic polythermal valley glacier

Peer reviewedPublisher PD

Antarctic subglacial hydrology: current knowledge and future challenges

AbstractFlood-carved landforms across the deglaciated terrain of Victoria Land, East Antarctica, provide convincing geomorphological evidence for the existence of subglacial drainage networks beneath the Antarctic ice sheet, and motivate research into the inaccessible environment beneath the contemporary ice sheet. Through this research, our understanding of Antarctic subglacial hydrology is steadily building, and this paper presents an overview of the current state of knowledge. The conceptualization of subglacial hydrological behaviour was developed at temperate and Arctic glaciers, and is thus less mature in the Antarctic. Geophysical and remote sensing observations have demonstrated that many subglacial lakes form part of a highly dynamic network of subglacial drainage beneath the Antarctic ice sheet. Recent research into subglacial water flows, other than those directly concerned with lakes, has discovered potentially significant impacts on ice stream dynamics, ice sheet mass balance, and supplies of water to the ocean potentially affecting circulation and nutrient productivity. Despite considerable advances in understanding there remain a number of grand challenges that must be overcome in order to improve our knowledge of these subglacial hydrological processes.</jats:p

Ecosystem services auctions: the last decade of research

ReviewAuctions offer potential cost-effectiveness improvements over other mechanisms for payments for ecosystem services (PES) contract allocation. However, evidence-based guidance for matching design to application is scarce and research priorities are unclear. To take stock of the current state of the art, we conducted a systematic review and thematic content analysis of 56 peer-reviewed journal articles discussing ES auctions published in the last decade. Auctions were approached from three overlapping perspectives: mechanism design, PES, and policy analysis. Five major themes emerged: (1) performance, including measures like cost-effectiveness and PES criteria like additionality; (2) information dynamics like price discovery and communication effects; (3) design innovations like risk-integrating and spatially coordinated mechanisms; (4) contextual variables like policy context and cultural values; and (5) participation factors. Additional attention from policymakers and continued efforts to coordinate research in this diverse and interdisciplinary subfield may be beneficialinfo:eu-repo/semantics/publishedVersio

Student Misbehaviors, Instructor Responses, And Connected Classroom Climate: Implications for the Basic Course

The concept of connected classroom climate focuses on student-to-student communication behaviors that are paramount in creating the climate of a class, especially in the basic course. While previous studies have focused on the positive and cooperative behaviors of students and instructors that may contribute to perceptions of classroom connectedness, the role that incivilities may play in detracting from or undermining a connected classroom climate has not been investigated. This study examines perceptions of a connected classroom climate and its relationships to student misbehaviors and instructor responses. A total of 542 university students enrolled in 30 sections of the basic public speaking course completed the Connected Classroom Climate Inventory (CCCI) and scales measuring student misbehaviors and teacher responses to student misbehaviors. Results showed that student perceptions of a connected classroom climate were inversely related to both inconsiderate and harassing student misbehaviors. The results also revealed a possible relationship between classroom connectedness and the manner in which instructors respond to students when they misbehave. These findings suggest that basic course instructors need to consider how to reduce student inconsideration and harassment misbehaviors in their classes, and how to positively respond to these behaviors when they do occur so that classroom connectedness is not diminished

An investigation into the mechanisms controlling seasonal speedup events at a High Arctic glacier

Seasonal variations in ice motion have been observed at several polythermal ice masses across the High Arctic, including the Greenland Ice Sheet. However, such variations in ice motion and their possible driving mechanisms are rarely incorporated in models of the response of High Arctic ice masses to predicted climate warming. Here we use a three-dimensional finite difference flow model, constrained by field data, to investigate seasonal variations in the distribution of basal sliding at polythermal John Evans Glacier, Ellesmere Island, Canada. Our results suggest that speedups observed at the surface during the melt season result directly from changes in rates of basal motion. They also suggest that stress gradient coupling is ineffective at transmitting basal motion anomalies to the upper part of the glacier, in contrast to findings from an earlier flow line study at the same glacier. We suggest that stress gradient coupling is limited through the effect of high drag imposed by a partially frozen bed and friction induced by valley walls and significant topographic pinning points. Our findings imply that stress gradient coupling may play a limited role in transmitting supraglacially forced basal motion anomalies through Arctic valley and outlet glaciers with complex topographic settings and highlight the importance of dynamically incorporating basal motion into models predicting the response of the Arctic's land ice to climate change