Magnetospheric lion roars

International audienceThe Equator-S magnetometer is very sensitive and has a sampling rate normally of 128 Hz. The high sampling rate for the first time allows detection of ELF waves between the ion cyclotron and the lower hybrid frequencies in the equatorial dawnside magnetosphere. The characteristics of these waves are virtually identical to the lion roars typically seen at the bottom of the magnetic troughs of magnetosheath mirror waves. The magnetospheric lion roars are near-monochromatic packets of electron whistler waves lasting for a few wave cycles only, typically 0.2 s. They are right-hand circularly polarized waves with typical amplitudes of 0.5 nT at around one tenth of the electron gyrofrequency. The cone angle between wave vector and ambient field is nearly always smaller than 1°

A case study of a radially polarized Pc4 event observed by the Equator-S satellite

International audienceA 16 mHz Pc4 pulsation was recorded on March 17, 1998, in the prenoon sector of the Earth's magnetosphere by the Equator-S satellite. The event is strongly localized in radial direction at approximately L = 5 and exhibits properties of a field line resonance such as an ellipticity change as seen by applying the method of the analytical signal to the magnetic field data. The azimuthal wave number was estimated as m \approx 150. We discuss whether this event can be explained by the FLR mechanism and find out that the change in ellipticity is more a general feature of a localized Alfvén wave than indicative of a resonant process

Report of the ICES\NAFO Joint Working Group on Deep-water Ecology (WGDEC), 11–15 March 2013, Floedevigen, Norway.

On 11 February 2013, the joint ICES/NAFO WGDEC, chaired by Francis Neat (UK) and attended by ten members met at the Institute for Marine Research in Floedevi-gen, Norway to consider the terms of reference (ToR) listed in Section 2. WGDEC was requested to update all records of deep-water vulnerable marine eco-systems (VMEs) in the North Atlantic. New data from a range of sources including multibeam echosounder surveys, fisheries surveys, habitat modelling and seabed imagery surveys was provided. For several areas across the North Atlantic, WGDEC makes recommendations for areas to be closed to bottom fisheries for the purposes of conservation of VMEs

Negotiating structural barriers to environmental collaborations in doctoral programmes

This is the final version. Available on open access from Wiley via the DOI in this recordData availability statement: No data was drawn on.This commentary reflects on the experiences of a cohort of human and physical geographers in enacting environmental collaborations during their doctoral studies. The authors identify three key structural barriers encountered whilst attempting a collaborative approach: (1) doctoral funding priorities, (2) doctoral resourcing and (3) assessing doctoral collaboration. The authors discuss how the negotiation of these encounters came to frame their understanding of collaborative approaches to environmental knowledge creation. Competitive application processes for doctoral studentships can encourage the overpromising of the impact of planned environmental collaboration, potentially co-opting the voices of partners/communities to satisfy doctoral funding requirements. Given insufficient funding of collaborations, the authors argue that this overpromising of doctoral research's impact can later result in difficult trade-offs between undertaking additional commitments at the expense of the career progression of the doctoral student, contributing to educational inequalities and scaling-back the initial plans at the cost of collaborators encountering environmental crises. The trade-off is further problematised by institutional assessment procedures that do not adequately recognise the more nuanced contributions of environmental collaborations and a prevailing culture promoting peer-review publishing. Overall, the commentary argues that these barriers help to reproduce inequalities in the distribution of voice in environmental scholarship, undermining efforts to democratise environmental knowledge creation in doctoral research. The authors call for specific structural reforms of doctoral programmes to help address these challenges and support a broader resistance to the inadequate resourcing and evaluation of environmental collaborative research in UK higher education.Engineering and Physical Sciences Research Council (EPSRC)Natural Environment Research Council (NERC)QUEX PhD studentship progra