Aerosol information content analysis of multi-angle high spectral resolution measurements and its benefit for high accuracy greenhouse gas retrievals Atmospheric Measurement Techniques DOI 10.5194/amt-5-1809-2012 27 July 2012 In this paper, we investigate the combined aerosol and greenhouse gas retrieval using multiple satellite viewing angles simultaneously. We find that this method greatly enhances the ability to retrieve aerosol properties by 2–3 degrees of freedom. Read more
Statistical adaptation of ALADIN RCM outputs over the French Alps – application to future climate and snow cover The Cryosphere DOI 10.5194/tc-6-785-2012 24 July 2012 In this study, snowpack scenarios are modelled across the French Alps using dynamically downscaled variables from the ALADIN Regional Climate Model (RCM) for the control period (1961–1990) and three emission scenarios (SRES B1, A1B and A2) for the mid- and late 21st century (2021–2050 and 2071–2100). Read more
Climatic and geologic controls on suspended sediment flux in the Sutlej River Valley, western Himalaya Hydrology and Earth System Sciences DOI 10.5194/hess-16-2193-2012 20 July 2012 Here, we present a comprehensive analysis of the spatiotemporal trends in suspended sediment flux based on daily data during the past decade (2001–2009) from four sites along the Sutlej River and from four of its main tributaries. Read more
Enhancing flood resilience through improved risk communications Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-2271-2012 20 July 2012 A framework of guiding recommendations for effective pre-flood and flood warning communications derived from the URFlood project (2nd ERA-Net CRUE Research Funding Initiative) from extensive quantitative and qualitative research in Finland, Ireland, Italy and Scotland is presented. Read more
Risk perception – issues for flood management in Europe Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-2299-2012 20 July 2012 Public perception of flood risk and flood risk information is often overlooked when developing flood risk management plans. As scientists and the public at large perceive risk in very different ways, flood risk management strategies are known to have failed in the past due to this disconnect between authorities and the public. This paper uses a novel approach in exploring the role of public perception in developing flood risk communication strategies in Europe. Read more
Detecting anthropogenic carbon dioxide uptake and ocean acidification in the North Atlantic Ocean Biogeosciences DOI 10.5194/bg-9-2509-2012 11 July 2012 Fossil fuel use, cement manufacture and land-use changes are the primary sources of anthropogenic carbon dioxide (CO2) to the atmosphere, with the ocean absorbing approximately 30% (Sabine et al., 2004). Ocean uptake and chemical equilibration of anthropogenic CO2 with seawater results in a gradual reduction in seawater pH and saturation states (Ω) for calcium carbonate (CaCO3) minerals in a process termed ocean acidification. Read more
Comparison of OH concentration measurements by DOAS and LIF during SAPHIR chamber experiments at high OH reactivity and low NO concentration Atmospheric Measurement Techniques DOI 10.5194/amt-5-1611-2012 11 July 2012 During recent field campaigns, hydroxyl radical (OH) concentrations that were measured by laser-induced fluorescence (LIF) were up to a factor of ten larger than predicted by current chemical models for conditions of high OH reactivity and low NO concentration. These discrepancies, which were observed in forests and urban-influenced rural environments, are so far not entirely understood. Read more
Searching for the seafloor signature of the 21 May 2003 Boumerdès earthquake offshore central Algeria Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-2159-2012 10 July 2012 Shaking by moderate to large earthquakes in the Mediterranean Sea has proved in the past to potentially trigger catastrophic sediment collapse and flow. On 21 May 2003, a magnitude 6.8 earthquake located near Boumerdès (central Algerian coast) triggered large turbidity currents responsible for 29 submarine cable breaks at the foot of the continental slope over ~150 km from west to east. Read more
Extrapolating glacier mass balance to the mountain-range scale: the European Alps 1900–2100 The Cryosphere DOI 10.5194/tc-6-713-2012 6 July 2012 This study addresses the extrapolation of in-situ glacier mass balance measurements to the mountain-range scale and aims at deriving time series of area-averaged mass balance and ice volume change for all glaciers in the European Alps for the period 1900–2100. Read more
Bioerosion by euendoliths decreases in phosphate-enriched skeletons of living corals Biogeosciences DOI 10.5194/bg-9-2377-2012 2 July 2012 While the role of microboring organisms, or euendoliths, is relatively well known in dead coral skeletons, their function in live corals remains poorly understood. They are suggested to behave like ectosymbionts or parasites, impacting their host’s health. However, the species composition of microboring communities, their abundance and dynamics in live corals under various environmental conditions have never been explored. Read more
Building an 18 000-year-long paleo-earthquake record from detailed deep-sea turbidite characterisation in Poverty Bay, New Zealand Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-2077-2012 27 June 2012 Our results show that the progressive characterisation of a turbidite record from a single sedimentary system can provide a continuous paleo-earthquake history in regions of short historical record and incomplete onland paleo-earthquake evidences. The systematic description of each turbidite enables us to infer the triggering mechanism. Read more
Novel water source for endolithic life in the hyperarid core of the Atacama Desert Biogeosciences DOI 10.5194/bg-9-2275-2012 26 June 2012 Our results explain how life has colonized and adapted to one of the most extreme environments on our planet, expanding the water activity envelope for life on Earth, and broadening the spectrum of possible habitats for life beyond our planet. Read more
Severe wind gust thresholds for Meteoalarm derived from uniform return periods in ECA&D Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-1969-2012 25 June 2012 In this study we present an alternative wind gust warning guideline for Meteoalarm, the severe weather warning website for Europe. There are unrealistically large differences in levels and issuing frequencies of all warning levels currently in use between neighbouring Meteoalarm countries. This study provides a guide for the Meteoalarm community to review their wind gust warning thresholds. Read more
Introduction to the European Monitoring and Evaluation Programme (EMEP) and observed atmospheric composition change during 1972–2009 Atmospheric Chemistry and Physics DOI 10.5194/acp-12-5447-2012 22 June 2012 European scale harmonized monitoring of atmospheric composition was initiated in the early 1970s, and the activity has generated a comprehensive dataset which allows the evaluation of regional and spatial trends of air pollution during a period of nearly 40 yr. Read more
Impact of heat and drought stress on arable crop production in Belgium Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-1911-2012 18 June 2012 Modelling approaches are needed to accelerate understanding of adverse weather impacts on crop performances and yields. The aim was to elicit biometeorological conditions that affect Belgian arable crop yield, commensurate with the scale of climatic impacts. Read more
Towards a merged satellite and in situ fluorescence ocean chlorophyll product Biogeosciences DOI 10.5194/bg-9-2111-2012 12 June 2012 Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represent the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Read more
Solar irradiance reduction to counteract radiative forcing from a quadrupling of CO2: climate responses simulated by four earth system models Earth System Dynamics DOI 10.5194/esd-3-63-2012 6 June 2012 In this study we compare the response of four state-of-the-art Earth system models to climate engineering under scenario G1 of two model intercomparison projects: GeoMIP (Geoengineering Model Intercomparison Project) and IMPLICC (EU project “Implications and risks of engineering solar radiation to limit climate change”). Read more
Organic matter dynamics and stable isotope signature as tracers of the sources of suspended sediment Biogeosciences DOI 10.5194/bg-9-1985-2012 4 June 2012 Suspended sediment (SS) and organic matter in rivers can harm brown trout Salmo trutta by affecting the health and fitness of free swimming fish and by causing siltation of the riverbed. The temporal and spatial dynamics of sediment, carbon (C), and nitrogen (N) during the brown trout spawning season in a small river of the Swiss Plateau were assessed and C isotopes as well as the C/N atomic ratio were used to distinguish autochthonous and allochthonous sources of organic matter in SS loads. Read more
The spatial structure of European wind storms as characterized by bivariate extreme-value Copulas Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-1769-2012 29 May 2012 The winds associated with extra-tropical cyclones are amongst the costliest natural perils in Europe. Re/insurance companies typically have insured exposure at multiple locations and hence the losses they incur from any individual storm crucially depend on that storm’s spatial structure. Motivated by this, this study investigates the spatial structure of the most extreme windstorms in Europe. Read more
Drivers of flood risk change in residential areas Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-1641-2012 23 May 2012 The observed increase of direct flood damage over the last decades may be caused by changes in the meteorological drivers of floods, or by changing land-use patterns and socio-economic developments. It is still widely unknown to which extent these factors will contribute to future flood risk changes. Read more
Photo-lability of deep ocean dissolved black carbon Biogeosciences DOI 10.5194/bg-9-1661-2012 9 May 2012 Dissolved black carbon (DBC) is a significant component of the oceanic dissolved organic carbon (DOC) pool. In the current study, the photo-lability of DBC, DOC and coloured dissolved organic matter (CDOM; ultraviolet-visible absorbance) were determined over the course of a 28 day irradiation of North Atlantic Deep Water under a solar simulator. Read more
On the role of ozone in long-term trends in the upper atmosphere-ionosphere system Annales Geophysicae DOI 10.5194/angeo-30-811-2012 8 May 2012 Recently, Walsh and Oliver (2011) suggested that the long-term cooling of the upper thermosphere (above 200 km) may be due largely to the stratospheric ozone depletion. Here, we show that the role of ozone is very important in the mesosphere and lower thermosphere but not in the upper thermosphere. Read more
Estimating the climate significance of halogen-driven ozone loss in the tropical marine troposphere Atmospheric Chemistry and Physics DOI 10.5194/acp-12-3939-2012 4 May 2012 We find that the implementation of oceanic halogen sources and chemistry in climate models is an important component of the natural background ozone budget and we suggest that it needs to be considered when estimating both preindustrial ozone baseline levels and long term changes in tropospheric ozone. Read more
The regulation of the air: a hypothesis Solid Earth DOI 10.5194/se-3-87-2012 12 March 2012 We propose the hypothesis that natural selection, acting on the specificity or preference for CO2 over O2 of the enzyme rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase), has controlled the CO2:O2 ratio of the atmosphere since the evolution of photosynthesis and has also sustained the Earth’s greenhouse-set surface temperature. Read more
Global characteristics of the lunar tidal modulation of the equatorial electrojet derived from CHAMP observations Annales Geophysicae DOI 10.5194/angeo-30-527-2012 8 March 2012 It has been known since many decades that lunar tide has an influence on the strength of the equatorial electrojet (EEJ). There has, however, never been a comprehensive study of the tidal effect on a global scale. Based on the continuous magnetic field measurements by the CHAMP satellite over 10 years it is possible to investigate the various aspects of lunar effects on the EEJ. Read more
Evidence of a possible turning point in solar UV-B over Canada, Europe and Japan Atmospheric Chemistry and Physics DOI 10.5194/acp-12-2469-2012 5 March 2012 This study examines the long-term variability of UV solar irradiances at 305 nm and 325 nm over selected sites in Canada, Europe and Japan. Site selection was restricted to the availability of the most complete UV spectroradiometric datasets during the period 1990–2011. The analysis includes the long-term variability of total ozone, aerosol optical depth and cloud fraction at the sites studied. Read more
A tsunami wave recorded near a glacier front Natural Hazards and Earth System Sciences DOI 10.5194/nhess-12-415-2012 27 February 2012 We observed a tsunami wave near the glacier front in the Temple Fjord (Spitsbergen). Two temperature and pressure recorders were deployed on a wire from the ice approximately 300 m from the glacier front. The measurements allowed us to estimate the wave number of these waves and the Young’s modulus of the ice. Read more
Revisiting “Narrow Bipolar Event” intracloud lightning using the FORTE satellite Annales Geophysicae DOI 10.5194/angeo-30-389-2012 24 February 2012 The lightning stroke called a “Narrow Bipolar Event”, or NBE, is an intracloud discharge responsible for significant charge redistribution. The NBE occurs within 10–20 μs, and some associated process emits irregular bursts of intense radio noise, fading at shorter timescales, sporadically during the charge transfer. Read more
Tomography of the 2011 Iwaki earthquake (M 7.0) and Fukushima nuclear power plant area Solid Earth DOI 10.5194/se-3-43-2012 14 February 2012 High-resolution tomographic images of the crust and upper mantle in and around the area of the 2011 Iwaki earthquake (M 7.0) and the Fukushima nuclear power plant are determined by inverting a large number of high-quality arrival times with both the finite-frequency and ray tomography methods. The similar structures under the Iwaki source area and the Fukushima nuclear power plant suggest that the security of the nuclear power plant site should be strengthened to withstand potential large earthquakes in the future. Read more
Magnetopause displacements: the possible role of dust Annales Geophysicae DOI 10.5194/angeo-29-2219-2011 1 December 2011 Large compressions of the magnetopause are proposed to occasionally result from temporary encounters of the magnetosphere with dust streams in interplanetary space. Such streams may have their origin in cometary dust tails or asteroids which cross the inner heliosphere or in meteoroids in Earth’s vicinity. Read more
