News & press Highlight articles

European Geosciences Union

www.egu.eu

Highlight articles

Some features of our web site require JavaScript to function properly. Please enable JavaScript in your browser.

1868 items found

10 20 50

DCMIP2016: a review of non-hydrostatic dynamical core design and intercomparison of participating models

Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth’s atmosphere. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP) workshop and summer school.

Impact of asymmetric uncertainties in ice sheet dynamics on regional sea level projections

Natural Hazards and Earth System Sciences
DOI 10.5194/nhess-17-2125-2017
4 December 2017

This paper provides a full range of possible future sea levels on a regional scale, since it includes extreme, but possible, contributions to sea level change from dynamical mass loss from the Greenland and Antarctica ice sheets. In contrast to the symmetric distribution used in the IPCC report, it is found that an asymmetric distribution toward high sea level change values locally can increase the mean sea level by 1.8 m this century.

Simulation of climate, ice sheets and CO2 evolution during the last four glacial cycles with an Earth system model of intermediate complexity

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.

The role of meteorological conditions and pollution control strategies in reducing air pollution in Beijing during APEC 2014 and Victory Parade 2015

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 PM_2.5 concentration during APEC 2014 and 38% and 25% during Parade 2015.

APEC 2014 and Victory Parade 2015">Read more

Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

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.

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).

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.

Climate of migration? How climate triggered migration from southwest Germany to North America during the 19th century

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.

A multilayer physically based snowpack model simulating direct and indirect radiative impacts of light-absorbing impurities in snow

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.

A new diagnostic for tropospheric ozone production

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.

Reviews and syntheses: on the roles trees play in building and plumbing the critical zone

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.

Basin-scale heterogeneity in Antarctic precipitation and its impact on surface mass variability

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.

Regional Antarctic snow accumulation over the past 1000 years

Regional Antarctic snow accumulation derived from 79 ice core records is evaluated as part of the PAGES Antarctica 2k working group. Our results show that surface mass balance for the total Antarctic ice sheet has increased at a rate of 7 ± 0.13 Gt dec^-1 since 1800 AD, representing a net reduction in sea level of ~ 0.02 mm dec^-1 since 1800 and ~ 0.04 mm dec^-1 since 1900 AD. The largest contribution is from the Antarctic Peninsula.

Towards representing human behavior and decision making in Earth system models – an overview of techniques and approaches

Today, human interactions with the Earth system lead to complex feedbacks between social and ecological dynamics. Modeling such feedbacks explicitly in Earth system models (ESMs) requires making assumptions about individual decision making and behavior, social interaction, and their aggregation. In this overview paper, we compare different modeling approaches and techniques and highlight important consequences of modeling assumptions. We illustrate them with examples from land-use modeling.

Making better sense of the mosaic of environmental measurement networks: a system-of-systems approach and quantitative assessment

Geoscientific Instrumentation, Methods and Data Systems
DOI 10.5194/gi-6-453-2017
6 November 2017

The term system-of-systems with respect to observational capabilities is frequently used, but what does it mean and how can it be assessed? Here, we define one possible interpretation of a system-of-systems architecture that is based upon demonstrable aspects of observing capabilities. We develop a set of assessment strands and then apply these to a set of atmospheric observational networks to decide which observations may be suitable for characterising satellite platforms in future work.

Methanesulfonic acid (MSA) migration in polar ice: data synthesis and theory

We combine a synthesis of 22 ice core records and a model of soluble impurity transport to investigate the enigmatic, post-depositional migration of methanesulfonic acid in polar ice. Our findings suggest that migration may be universal across coastal regions of Greenland and Antarctica, though it is mitigated at sites with higher accumulation and (or) lower impurity content. Records exhibiting severe migration may still be useful for inferring decadal and lower-frequency climate variability.

MSA) migration in polar ice: data synthesis and theory">Read more

Global consequences of afforestation and bioenergy cultivation on ecosystem service indicators

Many climate change mitigation scenarios require negative emissions from land management. However, environmental side effects are often not considered. Here, we use projections of future land use from two land-use models as input to a vegetation model. We show that carbon removal via bioenergy production or forest maintenance and expansion affect a range of ecosystem functions. Largest impacts are found for crop production, nitrogen losses, and emissions of biogenic volatile organic compounds.

Is there 1.5-million-year-old ice near Dome C, Antarctica?

The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ~ 800 000 years. Obtaining an older palaeoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we estimate the age of basal ice in the Dome C area. We find that old ice (> 1.5 Myr) likely exists in two regions a few tens of kilometres away from EDC:Little Dome C PatchandNorth Patch.

The Palaeoclimate and Terrestrial Exoplanet Radiative Transfer Model Intercomparison Project (PALAEOTRIP): experimental design and protocols

We provide the experimental designs and protocols for a community experiment to compare radiative transfer codes used for past climate on Earth, and for exoplanets.

PALAEOTRIP): experimental design and protocols">Read more

Impact of agricultural emission reductions on fine-particulate matter and public health

This study shows that agricultural emissions are important for air quality and their reduction can effectively reduce the concentration of fine particles and their associated premature mortality. Therefore, emission control policies, especially in North America and Europe, should also involve strong ammonia emission decreases to optimally reduce fine-particle concentration.