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This article explores how concepts from justice and ethics can inform energy decisionmaking and highlight the moral and equity dimensions of energy production and use. It defines "energy justice" as a global energy system that fairly distributes both the benefits and burdens of energy services, and one that contributes to more representative and inclusive energy decision-making. The primary contribution of the article is its focus on six new frontiers of future energy justice research. First is making the case for the involvement of non-Western justice theorists. Second is expanding beyond humans to look at the Rights of Nature or non-anthropocentric notions of justice. Third is focusing on cross-scalar issues of justice such as embodied emissions. Fourth is identifying business models and the co-benefits of justice. Fifth is better understanding the tradeoffs within energy justice principles. Sixth is exposing unjust discourses. In doing so, the article presents an agenda constituted by 30 research questions as well as an amended conceptual framework consisting of ten principles. The article argues in favor of "justice-aware" energy planning and policymaking, and it hopes that its (reconsidered) energy justice conceptual framework offers a critical tool to inform decision-making.

[1] We present subdaily ice flow measurements at four GPS sites between 36 and 72 km from the margin of a marine-terminating Greenland outlet glacier spanning the 2009 melt season. Our data show that >35 km from the margin, seasonal and shorter-time scale ice flow variations are controlled by surface melt-induced changes in subglacial hydrology. Following the onset of melting at each site, ice motion increased above background for up to 2 months with resultant up-glacier migration of both the onset and peak of acceleration. Later in our survey, ice flow at all sites decreased to below background. Multiple 1 to 15 day speedups increased ice motion by up to 40% above background. These events were typically accompanied by uplift and coincided with enhanced surface melt or lake drainage. Our results indicate that the subglacial drainage system evolved through the season with efficient drainage extending to at least 48 km inland during the melt season. While we can explain our observations with reference to evolution of the glacier drainage system, the net effect of the summer speed variations on annual motion is small (∼1%). This, in part, is because the speedups are compensated for by slowdowns beneath background associated with the establishment of an efficient subglacial drainage system. In addition, the speedups are less pronounced in comparison to land-terminating systems. Our results reveal similarities between the inland ice flow response of Greenland marine-and land-terminating outlet glaciers.

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The southernmost terrestrial extent of the Irish Sea Ice Stream (ISIS), which drained a large proportion of the last British-Irish Ice Sheet, impinged on to the Isles of Scilly during Marine Isotope Stage 2. However, the age of this ice limit has been contested and the interpretation that this occurred during the Last Glacial Maximum (LGM) remains controversial. This study reports new ages using optically stimulated luminescence (OSL) dating of outwash sediments at Battery, Tresco (25.5 AE 1.5 ka), and terrestrial cosmogenic nuclide exposure dating of boulders overlying till on Scilly Rock (25.9 AE 1.6 ka), which confirm that the ISIS reached the Isles of Scilly during the LGM. The ages demonstrate this ice advance on to the northern Isles of Scilly occurred at $26 ka around the time of increased ice-rafted debris in the adjacent marine record from the continental margin, which coincided with Heinrich Event 2 at $24 ka. OSL dating (19.6 AE 1.5 ka) of the post-glacial Hell Bay Gravel at Battery suggests there was then an $5-ka delay between primary deposition and aeolian reworking of the glacigenic sediment, during a time when the ISIS ice front was oscillating on and around the Llŷn Peninsula, $390 km to the north.

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Rates of ice-stream retreat over decades can be determined from repeated satellite surveys and over millennia by paleoenvironmental reconstructions. Centennial time scales are an important temporal gap in geological observations of value in process understanding and evaluation of numerical models. We address this temporal gap by developing a 3 ka and 123 km retreat time series for the Irish Sea ice stream (ISIS), a major outlet draining the last British-Irish ice sheet. The Llŷn Peninsula (northwest Wales, UK) contains numerous ice-marginal indicators from which we reconstructed a robust chronological framework of margin oscillations. The landscape documents the retreat of a former marine-terminating ice stream through a topographic constriction, across a reverse bed slope, and across variations in calving margin width. New dating constraints for this sequence were integrated in a Bayesian sequence model to develop a high-resolution ice-retreat chronology. Our results show that retreat of the ISIS during the period 24-20 ka displayed centennial-scale oscillatory behavior of the margin despite relatively stable climatic, oceanic, and relative sea-level forcing mechanisms. Faster retreat rates coincided with greater axial trough depths as the ice passed over a reverse bed slope and the calving margin widened (from 65 to 139 km). The geological observations presented here over a 123-km-long ice-retreat sequence are consistent with theory that marine-based ice can be inherently unstable when passing over a reverse bed slope, but also that wider calving margins lead to much faster ice retreat.