Moisture transport and Antarctic sea ice: austral spring 2016 event Earth System Dynamics DOI 10.5194/esd-9-939-2018 4 July 2018 In austral spring 2016 the Antarctic region experienced anomalous sea ice retreat in all sectors, with sea ice extent in October and November 2016 being the lowest in the Southern Hemisphere over the observational record (1979–present). The extreme sea ice retreat was accompanied by the wettest and warmest spring on record, over large areas covering the Indian ocean, the Ross Sea, and the Weddell Sea. Read more
HESS Opinions: Science in today’s media landscape – challenges and lessons from hydrologists and journalists Hydrology and Earth System Sciences DOI 10.5194/hess-22-3589-2018 4 July 2018 Media play a key role in the communication between scientists and the general public. However, the interaction between scientists and journalists is not always straightforward. In this opinion paper, we present insights from hydrologists and journalists into the benefits, aftermath and potential pitfalls of science–media interaction. We aim to encourage scientists to participate in the diverse and evolving media landscape, and we call on the scientific community to support scientists who do so. HESS Opinions: Science in today’s media landscape – challenges and lessons from hydrologists and journalists">Read more
High- and low-temperature pyrolysis profiles describe volatile organic compound emissions from western US wildfire fuels Atmospheric Chemistry and Physics DOI 10.5194/acp-18-9263-2018 3 July 2018 We found that on average 85 % of the VOC emissions from biomass burning across various fuels representative of the western US (including various coniferous and chaparral fuels) can be explained using only two emission profiles: (i) a high-temperature pyrolysis profile and (ii) a low-temperature pyrolysis profile. The high-temperature profile is quantitatively similar between different fuel types (r2 > 0.84), and likewise for the low-temperature profile. Read more
Transfer entropy and cumulant-based cost as measures of nonlinear causal relationships in space plasmas: applications to Dst Annales Geophysicae DOI 10.5194/angeo-36-945-2018 2 July 2018 The magnetospheric response to the solar wind is nonlinear. Information theoretical tools are able to characterize the nonlinearities in the system. We show that nonlinear significance ofDstpeaks at lags of 3–12 hours which can be attributed toVBs, which also exhibits similar behavior. However, the nonlinear significance that peaks at lags of 25, 50, and 90 hours can be attributed to internal dynamics, which may be related to the relaxation of the ring current. Read more
Brief communication: Candidate sites of 1.5 Myr old ice 37 km southwest of the Dome C summit, East Antarctica The Cryosphere DOI 10.5194/tc-12-2167-2018 28 June 2018 Locating a suitable drill site is a key step in the Antarctic oldest-ice challenge. Here we have conducted a 3-D ice flow simulation in the region of Dome C using a refined bedrock description. Five selection criteria are computed that together provide an objective overview on the local ice flow conditions. We delineate kilometer-scale favorable areas that overlap with the ones recently proposed by another group. We propose a few drill sites that should be surveyed during the next field seasons. Read more
Quality assessment of the Ozone_cci Climate Research Data Package (release 2017) – Part 2: Ground-based validation of nadir ozone profile data products Atmospheric Measurement Techniques DOI 10.5194/amt-11-3769-2018 27 June 2018 This work, performed at the Royal Belgian Institute for Space Aeronomy and the second in a series of four Ozone_cci papers, reports for the first time on data content studies, information content studies, and comparisons with co-located ground-based reference observations for all 13 nadir ozone profile data products that are part of the Climate Research Data Package (CRDP) on atmospheric ozone of the European Space Agency’s Climate Change Initiative. Read more
Electromagnetic characteristics of ENSO Ocean Science DOI 10.5194/os-14-515-2018 25 June 2018 The study finds that changes in seawater temperature due to El Niño and La Niña, anomalous warm and cold events, are in principle detectable by means of the oceanic tidally induced magnetic field. Furthermore, subsurface processes in the onset of those anomalous events lead the surface processes by several months. This causes a lead in the oceanic tidally induced magnetic field signals over sea-surface temperature signals. ENSO">Read more
Acoustic mapping of mixed layer depth Ocean Science DOI 10.5194/os-14-503-2018 22 June 2018 The ocean surface mixed layer depth (MLD) is an important parameter within several research disciplines, as variations in the MLD influence air–sea CO2 exchange and ocean primary production. A new method is presented in which acoustic mapping of the MLD is done remotely by means of echo sounders. This method allows for observations of high-frequency variability in the MLD, as horizontal and temporal resolutions can be increased by orders of magnitude compared to traditional in situ measurements. Read more
New high-frequency (7–12 kHz) quasi-periodic VLF emissions observed on the ground at L ∼ 5.5 Annales Geophysicae DOI 10.5194/angeo-36-915-2018 21 June 2018 We reveal previously unknown quasi-periodic (QP) VLF emissions at the unusually high-frequency band of ~ 7–11 kHz by applying the digital filtering of strong sferics to the ground-based VLF data recorded at Kannuslehto station (KAN). In one event, the spectral–temporal forms of the emissions looked like a series of giantbullets, with very abrupt cessation. In the second event, the modulation period was about 3 min under the absence of the simultaneous geomagnetic pulsations. VLF emissions observed on the ground at L ∼ 5.5">Read more
Transfer of diazotroph-derived nitrogen to the planktonic food web across gradients of N2 fixation activity and diversity in the western tropical South Pacific Ocean Biogeosciences DOI 10.5194/bg-15-3795-2018 21 June 2018 Biological dinitrogen (N2) fixation provides the major source of new nitrogen (N) to the open ocean, contributing more than atmospheric deposition and riverine inputs to the N supply. Yet the fate of the diazotroph-derived N (DDN) in the planktonic food web is poorly understood. The main goals of this study were (i) to quantify how much of DDN is released to the dissolved pool during N2 fixation and how much is transferred to bacteria, phytoplankton and zooplankton, and (ii) to compare the DDN release and transfer efficiencies under contrasting N2 fixation activity and diversity in the oligotrophic waters of the western tropical South Pacific Ocean. Read more