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Modelling environmental influences on calving at Helheim Glacier in eastern Greenland

Calving is an important mass-loss process for many glaciers worldwide, and has been assumed to respond to a variety of environmental influences. We present a grounded, flowline tidewater glacier model using a physically-based calving mechanism, applied to Helheim Glacier, eastern Greenland.

Effects of stratospheric ozone recovery on photochemistry and ozone air quality in the troposphere

In this study, the authors examine the implications of stratospheric ozone recovery for the tropospheric chemistry and ozone air quality with a global chemical transport model (GEOS-Chem).

Little Ice Age climate reconstruction from ensemble reanalysis of Alpine glacier fluctuations

Here the author analyses terminus position histories from an ensemble of seven glaciers in the Alps with a macroscopic model of glacier dynamics to derive a history of glacier equilibrium line altitude for the time span 400–2010 C.E.

Earthquake-induced ground failures in Italy from a reviewed database

Natural Hazards and Earth System Sciences
DOI 10.5194/nhess-14-799-2014
10 April 2014

A database of earthquake-induced ground failures in Italy is presented, and the related content is analysed. The catalogue collects data regarding landslides, liquefaction, ground cracks, surface faulting and ground changes triggered by earthquakes of Mercalli epicentral intensity 8 or greater that occurred in the last millennium in Italy.

Fracture-induced softening for large-scale ice dynamics

To account for the macroscopic effect of fracture processes on large-scale viscous ice dynamics (i.e., ice-shelf scale), the authors apply a continuum representation of fractures and related fracture growth into the prognostic Parallel Ice Sheet Model and compare the results to observations.

Regional and inter-regional effects in evolving climate networks

In this study we identify the sources of the evolving network characteristics by considering a reduced-dimensionality description of the climate system using network nodes given by rotated principal component analysis. The time evolution of structures in local intra-component networks is studied and compared to evolving inter-component connectivity.

Modelling global-scale climate impacts of the late Miocene Messinian Salinity Crisis

By running extreme, sensitivity-type experiments with a fully coupled ocean–atmosphere general circulation model, this paper investigates the potential of various Messinian Salinity Crisis Mediterranean Outflow Water scenarios to impact global-scale climate.

Further evidence of important environmental information content in red-to-green ratios as depicted in paintings by great masters

In this paper, the authors examine sunsets painted by famous artists as proxy information for the aerosol optical depth after major volcanic eruptions.

Characterization of submicron aerosols during a month of serious pollution in Beijing, 2013

In January 2013, Beijing experienced several serious haze events. To achieve a better understanding of the characteristics, sources and processes of aerosols during this month, an Aerodyne high-resolution time-of-flight aerosol mass spectrometer was deployed at an urban site between 1 January and 1 February 2013 to obtain the size-resolved chemical composition of non-refractory submicron particles.

Uncertainty analysis of projections of ozone-depleting substances: mixing ratios, EESC, ODPs, and GWPs

Here the authors present a comprehensive uncertainty analysis of future mixing ratios of ozone-depleting substances (ODPs), levels of equivalent effective stratospheric chlorine (EESC), ozone depletion potentials, and global warming potentials (GWPs).

EESC, ODPs, and GWPs">Read more

The challenge of simulating the warmth of the mid-Miocene climatic optimum in CESM1

In this paper, the authors use the recently released Community Earth System Model (CESM1.0) with a slab ocean to simulate the mid-Miocene climatic optimum, incorporating recent Miocene CO₂ reconstructions of 400 ppm (parts per million).

Subsurface pH and carbonate saturation state of aragonite on the Chinese side of the North Yellow Sea: seasonal variations and controls

Based upon eight field surveys conducted between May 2011 and May 2012, we investigated seasonal variations in pH, carbonate saturation state of aragonite, and ancillary data on the Chinese side of the North Yellow Sea.

Exploring local adaptation and the ocean acidification seascape – studies in the California Current Large Marine Ecosystem

Here we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast.

Incidence of rough and irregular atmospheric ice particles from Small Ice Detector 3 measurements

2D light-scattering patterns were obtained in situ for the first time using the Small Ice Detector 3 probe during several flights in a variety of mid-latitude mixed-phase and cirrus clouds.

Observed decline of the Atlantic meridional overturning circulation 2004–2012

Ocean Science
DOI 10.5194/os-10-29-2014
6 February 2014

The Atlantic meridional overturning circulation and its component parts are monitored by combining a transatlantic array of moored instruments with submarine-cable-based measurements of the Gulf Stream and satellite derived Ekman transport. The time series has recently been extended to October 2012 and the results show a downward trend since 2004.

Using palaeo-climate comparisons to constrain future projections in CMIP5

We present a selection of methodologies for using the palaeo-climate model component of the Coupled Model Intercomparison Project (Phase 5) to attempt to constrain future climate projections using the same models.

Salinity changes in the Agulhas leakage area recorded by stable hydrogen isotopes of C₃₇ alkenones during Termination I and II

We reconstructed sea surface salinity changes using alkenone δD, and paleo-sea surface temperature using TEX^H₈₆ and U^K’₃₇, from two sediment cores located in the Agulhas leakage area during Termination I and II.

Autonomous thermal camera system for monitoring the active lava lake at Erebus volcano, Antarctica

Geoscientific Instrumentation, Methods and Data Systems
DOI 10.5194/gi-3-13-2014
5 February 2014

In December 2012, the Mount Erebus Volcano Observatory installed a thermal infrared camera system to monitor the volcano’s active lava lake. The new system is designed to be autonomous, and capable of capturing images of the lava lake continuously throughout the year.

China’s dimming and brightening: evidence, causes and hydrological implications

In this study, we synthesize reliable results and conclusively address recent advances and insufficiencies in studies on dimming and brightening in China.

Microphysical properties and high ice water content in continental and oceanic mesoscale convective systems and potential implications for commercial aircraft at flight altitude

Two complementary case studies are conducted to analyse convective system properties in the region where strong cloud-top lidar backscatter anomalies are observed as reported by Platt et al. (2011).

Regional variability of acidification in the Arctic: a sea of contrasts

In this study, we use an ocean-only general circulation model, with embedded biogeochemistry and a comprehensive description of the ocean carbon cycle, to study the response of pH and saturation states of calcite and aragonite to rising atmospheric pCO₂and changing climate in the Arctic Ocean.

Weathering by tree-root-associating fungi diminishes under simulated Cenozoic atmospheric CO₂decline

We report experimental evidence for a negative feedback across a declining Cenozoic [CO₂]_a range from 1500 to 200 ppm, whereby low [CO₂]_a curtails mineral surface alteration via trenching and etch pitting by arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) fungal partners of tree roots.

Ensemble projections of future streamflow droughts in Europe

This paper addresses the issue of future developments in streamflow drought characteristics across Europe.

Seabed topography beneath Larsen C Ice Shelf from seismic soundings

The Cryosphere
DOI 10.5194/tc-8-1-2014
2 January 2014

Seismic reflection soundings of ice thickness and seabed depth were acquired on the Larsen C Ice Shelf in order to test a sub-ice shelf bathymetry model derived from the inversion of IceBridge gravity data.

The surface temperatures of Earth: steps towards integrated understanding of variability and change

Geoscientific Instrumentation, Methods and Data Systems
DOI 10.5194/gi-2-305-2013
18 December 2013

In a community-based activity in June 2012, the EarthTemp Network brought together 55 researchers from five continents to improve the interaction between scientific communities who focus on surface temperature in particular domains, to exploit the strengths of different observing systems and to better meet the needs of different communities.

Quantifying mesoscale soil moisture with the cosmic-ray rover

This paper explores the challenges and opportunities for mapping soil moisture over large areas using the cosmic-ray rover.

Statistical analysis to characterize transport of nutrients in groundwater near an abandoned feedlot

Surface water from a lagoon and groundwater samples from 17 wells within and near an abandoned feedlot in northwestern Minnesota, USA, were analyzed for carbon, nutrients, and field parameters.

A simple explanation for the sensitivity of the hydrologic cycle to surface temperature and solar radiation and its implications for global climate change

The global hydrologic cycle is likely to increase in strength with global warming, although some studies indicate that warming due to solar absorption may result in a different sensitivity than warming due to an elevated greenhouse effect. Here we show that these sensitivities of the hydrologic cycle can be derived analytically from an extremely simple surface energy balance model that is constrained by the assumption that vertical convective exchange within the atmosphere operates at the thermodynamic limit of maximum power.

Seasonal variations of sea–air CO₂ fluxes in the largest tropical marginal sea (South China Sea) based on multiple-year underway measurements

Based upon 14 field surveys conducted between 2003 and 2008, this paper shows that the seasonal pattern of sea surface partial pressure of CO₂ (pCO₂) and sea–air CO₂ fluxes differed among four different physical–biogeochemical domains in the South China Sea proper.

Voyager 2 observation of the multifractal spectrum in the heliosphere and the heliosheath

This paper looks in detail at the multifractal scaling of the fluctuations in the interplanetary magnetic field strength as measured onboard Voyager 2 in the entire heliosphere and even in the heliosheath.

Rainfall estimation using moving cars as rain gauges – laboratory experiments

The spatial assessment of short time-step precipitation is a challenging task. Low density of observation networks, as well as the bias in radar rainfall estimation motivated the new idea of exploiting cars as moving rain gauges with windshield wipers or optical sensors as measurement devices.

Arctic stratospheric dehydration – Part 1: Unprecedented observation of vertical redistribution of water

This paper presents high-resolution measurements of water vapour, aerosols and clouds in the Arctic stratosphere in January and February 2010 carried out by in situ instrumentation on balloon sondes and high-altitude aircraft combined with satellite observations.

Quantifying aerosol mixing state with entropy and diversity measures

This paper presents the first quantitative metric for aerosol population mixing state, defined as the distribution of per-particle chemical species composition.

Paleosols in the Transantarctic Mountains: indicators of environmental change

Solid Earth
DOI 10.5194/se-4-451-2013
20 November 2013

Paleosols on unconsolidated deposits are emphasized in this study. Examples are given from the McMurdo Dry Valleys (78° S) and two outlet glaciers in the central and southern TAMS, including the Hatherton–Darwin Glacier region (80° S) and the Beardmore Glacier region (85°30’ S).

Inverse streamflow routing

Here we develop a methodology to invert the routing process, i.e., to derive the spatially distributed runoff from streamflow (e.g., measured at gauge stations) by inverting an arbitrary linear routing model using fixed interval smoothing.

Peak glacial ¹⁴C ventilation ages suggest major draw-down of carbon into the abyssal ocean

Here we present a new, though still fragmentary, ocean-wide Δ¹⁴C data set showing that during the Last Glacial Maximum (LGM) and Heinrich Stadial 1 (HS-1) the maximum ¹⁴C age difference between ocean deep waters and the atmosphere exceeded the modern values by up to 1500 ¹⁴C yr, in the extreme reaching 5100 ¹⁴C yr.

Heterogeneous formation of polar stratospheric clouds – Part 2: Nucleation of ice on synoptic scales

This paper provides compelling evidence for the importance of heterogeneous nucleation, likely on solid particles of meteoritic origin, and of small-scale temperature fluctuations, for the formation of ice particles in the Arctic stratosphere.

Where to find 1.5 million yr old ice for the IPICS “Oldest-Ice” ice core

The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet

IPICS “Oldest-Ice” ice core">Read more

Ratios among atmospheric trace gases together with winds imply exploitable information for bird navigation: a model elucidating experimental results

A model of avian goal-oriented navigation is described that is based on two empirical findings building a bridge from ornithology to atmospheric chemistry.

A thermodynamic approach to link self-organization, preferential flow and rainfall–runoff behaviour

This study investigates whether a thermodynamically optimal hillslope structure can, if existent, serve as a first guess for uncalibrated predictions of rainfall–runoff.

Filamentary structure in chemical tracer distributions near the subtropical jet following a wave breaking event

This paper presents a set of observations and analyses of trace gas cross sections in the extratropical upper troposphere/lower stratosphere (UTLS).

Nitrous Oxide (N₂O) production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts

Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N₂O) is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited.

Global monitoring of terrestrial chlorophyll fluorescence from moderate-spectral-resolution near-infrared satellite measurements: methodology, simulations, and application to GOME-2

Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption.

GOME-2">Read more

Cloud-resolving simulations of mercury scavenging and deposition in thunderstorms

This study examines dynamical and microphysical features of convective clouds that affect mercury (Hg) wet scavenging and concentrations in rainfall.

Carbonate mineral saturation states in the East China Sea: present conditions and future scenarios

To assess the impact of rising atmospheric CO₂ and eutrophication on the carbonate chemistry of the East China Sea shelf waters, saturation states (Ω) for two important biologically relevant carbonate minerals were calculated throughout the water column.

A novel salinity proxy based on Na incorporation into foraminiferal calcite

This study investigates the impact of salinity on foraminiferal Na/Ca values by laser ablation ICP-MS analyses of specimens of the benthic foraminifer Ammonia tepida cultured at a range of salinities (30.0–38.6).

Critical impacts of global warming on land ecosystems

Here we present a macro-scale analysis of climate change impacts on terrestrial ecosystems based on newly developed sets of climate scenarios featuring a step-wise sampling of global mean temperature increase between 1.5 and 5 K by 2100.

Remote sensing of LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes

The purpose of this study is to use field-based and satellite remote-sensing-based methods to assess leaf nitrogen pools in five diverse European agricultural landscapes located in Denmark, Scotland (United Kingdom), Poland, the Netherlands and Italy.

LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes">Read more

Naphthalene SOA: redox activity and naphthoquinone gas–particle partitioning

Chamber secondary organic aerosol from low-NO_x photooxidation of naphthalene by hydroxyl radical was examined with respect to its redox cycling behaviour using the dithiothreitol assay.

SOA: redox activity and naphthoquinone gas–particle partitioning">Read more

Multiple stressors of ocean ecosystems in the 21st century: projections with CMIP5 models

Ocean ecosystems are increasingly stressed by human-induced changes of their physical, chemical and biological environment. Here, we use the most recent simulations performed in the framework of the Coupled Model Intercomparison Project 5 to assess how stressors such as warming, acidification deoxygenation and changes in primary productivity by marine phytoplankton, may evolve over the course of the 21st century.