The blue suns of 1831: was the eruption of Ferdinandea, near Sicily, one of the largest volcanic climate forcing events of the nineteenth century? Climate of the Past DOI 10.5194/cp-17-2607-2021 16 March 2022 An unidentified eruption in 1831 was one of the largest volcanic climate forcing events of the nineteenth century. We use reported observations of a blue sun to reconstruct the transport of an aerosol plume from that eruption and, hence, identify it as the 1831 eruption of Ferdinandea, near Sicily. We propose that, although it was only a modest eruption, its volcanic plume was enriched with sulphur from sedimentary deposits and that meteorological conditions helped it reach the stratosphere. Read more
Brief communication: A roadmap towards credible projections of ice sheet contribution to sea level The Cryosphere DOI 10.5194/tc-15-5705-2021 14 March 2022 Estimating how much ice loss from Greenland and Antarctica will contribute to sea level rise is of critical societal importance. However, our analysis shows that recent efforts are not trustworthy because the models fail at reproducing contemporary ice melt. Here we present a roadmap towards making more credible estimates of ice sheet melt. Read more
Options to correct local turbulent flux measurements for large-scale fluxes using an approach based on large-eddy simulation Atmospheric Measurement Techniques DOI 10.5194/amt-14-7835-2021 11 March 2022 Turbulent flux measurements suffer from a general systematic underestimation. One reason for this bias is non-local transport by large-scale circulations. A recently developed model for this additional transport of sensible and latent energy is evaluated for three different test sites. Different options on how to apply this correction are presented, and the results are evaluated against independent measurements. Read more
Dynamics of variable dusk–dawn flow associated with magnetotail current sheet flapping Annales Geophysicae DOI 10.5194/angeo-39-1037-2021 9 March 2022 The sun’s magnetic field is carried across space by the solar wind – a hot plasma “stream” of ions and electrons – forming the interplanetary magnetic field (IMF). The IMF can introduce asymmetries in the Earth’s magnetic field, giving plasma flowing within it a direction dependent on IMF orientation. Electric currents in near-Earth space can also influence these plasma flows. We investigate these two competing mechanisms and find that the currents can prevent the IMF from controlling the flow. Read more
Identifying community values related to heat: recommendations for forecast and health risk communication Geoscience Communication DOI 10.5194/gc-4-517-2021 7 March 2022 This paper presents an analysis of public responses to U.S. National Weather Service heat-related Facebook posts for the Phoenix (Arizona) County Warning Area to identify community norms that may present challenges to the effectiveness of heat risk communication. Findings suggest that local audiences tend to view heat as normal and the ability to withstand heat as a marker of community identity. Recommendations are provided for harnessing those norms to promote positive behavioural change. Read more
Modelling the volcanic ash plume from Eyjafjallajökull eruption (May 2010) over Europe: evaluation of the benefit of source term improvements and of the assimilation of aerosol measurements Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3731-2021 4 March 2022 Volcanic eruptions that spread out ash over large areas, like Eyjafjallajökull in 2010, may have huge economic consequences due to flight cancellations. In this article, we demonstrate the benefits of source term improvement and of data assimilation for quantifying volcanic ash concentrations. The work, which was supported by the EUNADICS-AV project, is the first one, to our knowledge, that demonstrates the benefit of the assimilation of ground-based lidar data over Europe during an eruption. Read more
Ubiquity of human-induced changes in climate variability Earth System Dynamics DOI 10.5194/esd-12-1393-2021 2 March 2022 A large ensemble of simulations with 100 members has been conducted with the state-of-the-art CESM2 Earth system model, using historical and SSP3-7.0 forcing. Our main finding is that there are significant changes in the variance of the Earth system in response to anthropogenic forcing, with these changes spanning a broad range of variables important to impacts for human populations and ecosystems. Read more
SELF v1.0: a minimal physical model for predicting time of freeze-up in lakes Geoscientific Model Development DOI 10.5194/gmd-14-7527-2021 28 February 2022 The time when lakes freeze varies considerably from year to year. A common way to predict it is to use negative degree days, i.e., the sum of air temperatures below 0°C, a proxy for the heat lost to the atmosphere. Here, we show that this is insufficient as the mixing of the surface layer induced by wind tends to delay the formation of ice. To do so, we developed a minimal model based on a simplified energy balance, which can be used both for large-scale analyses and short-term predictions. SELF v1.0: a minimal physical model for predicting time of freeze-up in lakes">Read more
Annual exposure to polycyclic aromatic hydrocarbons in urban environments linked to wintertime wood-burning episodes Atmospheric Chemistry and Physics DOI 10.5194/acp-21-17865-2021 25 February 2022 We analyse observations from year-long measurements at Athens, Greece. Nighttime wintertime PAH levels are 4 times higher than daytime, and wintertime values are 15 times higher than summertime. Biomass burning aerosol during wintertime pollution events is responsible for these significant wintertime enhancements and accounts for 43 % of the population exposure to PAH carcinogenic risk. Biomass burning poses additional health risks beyond those associated with the high PM levels that develop. Read more
Assessing the dependence structure between oceanographic, fluvial, and pluvial flooding drivers along the United States coastline Hydrology and Earth System Sciences DOI 10.5194/hess-25-6203-2021 23 February 2022 We analyse dependences between different flooding drivers around the USA coastline, where the Gulf of Mexico and the southeastern and southwestern coasts are regions of high dependence between flooding drivers. Dependence is higher during the tropical season in the Gulf and at some locations on the East Coast but higher during the extratropical season on the West Coast. The analysis gives new insights on locations, driver combinations, and the time of the year when compound flooding is likely. Read more
