Simulation of climate, ice sheets and CO2 evolution during the last four glacial cycles with an Earth system model of intermediate complexity Climate of the Past DOI 10.5194/cp-13-1695-2017 29 November 2017 Ice cores reveal that atmospheric CO2 concentration varied synchronously with the global ice volume. Explaining the mechanism of glacial–interglacial variations of atmospheric CO2 concentrations and the link between CO2 and ice sheets evolution still remains a challenge. Here using the Earth system model of intermediate complexity we performed for the first time simulations of co-evolution of climate, ice sheets and carbon cycle using the astronomical forcing as the only external forcing. Read more
The role of meteorological conditions and pollution control strategies in reducing air pollution in Beijing during APEC 2014 and Victory Parade 2015 Atmospheric Chemistry and Physics DOI 10.5194/acp-17-13921-2017 23 November 2017 The generalized linear regression model (GLM), even based only on meteorological parameters, could be satisfactory to estimate the contribution of meteorological conditions in reducing air pollution and hence the contribution of control strategies in reducing air pollution. Using the GLM, we found that the meteorological conditions and pollution control strategies contributed 30% and 28% to the reduction of the PM2.5 concentration during APEC 2014 and 38% and 25% during Parade 2015. Read more
Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation Climate of the Past DOI 10.5194/cp-13-1635-2017 22 November 2017 Stratigraphic trends in the carbon isotope composition of calcium carbonate rock can be used as a stratigraphic tool. An important assumption when using these isotope chemical records is that they record a globally universal signal of marine water chemistry. We show that carbon isotope scatter on a confined centimetre stratigraphic scale appears to represent a signal of microbial activity. However, long-term carbon isotope trends are still compatible with a primary isotope imprint. Read more
When probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 1: Model components for sources parameterization Natural Hazards and Earth System Sciences DOI 10.5194/nhess-17-1981-2017 22 November 2017 The volcanic region of Mt. Etna (Sicily, Italy) represents a perfect lab for testing innovative approaches to seismic hazard assessment. We present here the model components and the procedures adopted for defining seismic sources to be used in a new generation of probabilistic seismic hazard assessment, the first results and maps of which are presented in a companion paper, Peruzza et al. (2017). Read more
When probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 2: Computational implementation and first results Natural Hazards and Earth System Sciences DOI 10.5194/nhess-17-1999-2017 22 November 2017 It is well known that volcanoes and earthquakes are associated, and some active volcanoes cause damaging earthquakes. Nonetheless, volcanoes usually are not pinpointed on a hazard map, as the effects of shallow, volcanic earthquakes can be overshadowed by stronger tectonic earthquakes in the region, particularly when long exposure periods are considered. In this study we faced some challenges with software implementations and original concept scheme for an original PSHA at Mt. Etna, Italy. Read more
Climate of migration? How climate triggered migration from southwest Germany to North America during the 19th century Climate of the Past DOI 10.5194/cp-13-1573-2017 21 November 2017 This paper presents the extent to which climate, harvest and prices influenced the major migration waves from southwest Germany into North America during the 19th century, a century of dramatic climatic and societal changes. Read more
A multilayer physically based snowpack model simulating direct and indirect radiative impacts of light-absorbing impurities in snow The Cryosphere DOI 10.5194/tc-11-2633-2017 20 November 2017 Light-absorbing impurities deposited on snow, such as soot or dust, strongly modify its evolution. We implemented impurity deposition and evolution in a detailed snowpack model, thereby expanding the reach of such models into addressing the subtle interplays between snow physics and impurities’ optical properties. Model results were evaluated based on innovative field observations at an Alpine site. This allows future investigations in the fields of climate, hydrology and avalanche prediction. Read more
A new diagnostic for tropospheric ozone production Atmospheric Chemistry and Physics DOI 10.5194/acp-17-13669-2017 17 November 2017 Understanding tropospheric ozone chemistry has been at the centre of the field of atmospheric chemistry for the last 30 years. However, our conceptual approach to diagnosing ozone production in global models has not advanced in this time. Our work presents a new and powerful approach for diagnosing tropospheric ozone production, providing a significant enhancement in our ability to understand the processes controlling ozone and how we can validate our assessment of these processes. Read more
Reviews and syntheses: on the roles trees play in building and plumbing the critical zone Biogeosciences DOI 10.5194/bg-14-5115-2017 17 November 2017 This review represents the outcome from an invigorating workshop discussion that involved tree physiologists, geomorphologists, ecologists, geochemists, and hydrologists and developed nine hypotheses that could be tested. We argue these hypotheses point to the essence of issues we must explore if we are to understand how the natural system of the earth surface evolves, and how humans will affect its evolution. This paper will create discussion and interest both before and after publication. Read more
Basin-scale heterogeneity in Antarctic precipitation and its impact on surface mass variability The Cryosphere DOI 10.5194/tc-11-2595-2017 15 November 2017 In this CESM modeling study, we uncover regional relationships in snowfall across Antarctica that are corroborated by regional modeling and ice core records. These relationships are driven by variability in large-scale atmospheric moisture transport and dampen overall Antarctic snowfall variability, with implications for Antarctic-sourced sea level variability and detection of an emergent anthropogenic signal in Antarctic mass trends. Read more