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Contrasting Greenland and Antarctic temperatures during the last glacial period (115,000 to 11,650 years ago) are thought to have been driven by imbalances in the rates of formation of North Atlantic and Antarctic Deep Water (the 'bipolar seesaw'). Here we exploit a bidecadally resolved 14C data set obtained from New Zealand kauri (Agathis australis) to undertake high-precision alignment of key cl

This study is based on fine-mode aerosol samples collected in the upper troposphere (UT) and the lowermost stratosphere (LMS) of the Northern Hemisphere extratropics during monthly intercontinental flights at 8.8-12 km altitude of the IAGOS-CARIBIC platform in the time period 1999-2014. The samples were analyzed for a large number of chemical elements using the accelerator-based methods PIXE (part

Here we report new reconstructions of winter temperature and summer moisture during the past millennium in southeastern Sweden, based on stable-isotope data from a composite tree-ring sequence, that further enhances our knowledge and understanding of seasonal climate variability in the Northern Hemisphere over the past millennium. Key features of these new climate proxy records include evidence fo

Knowledge on the occurrence rate of extreme solar storms is strongly limited by the relatively recent advent of satellite monitoring of the Sun. To extend our perspective of solar storms prior to the satellite era and because atmospheric ionization induced by solar energetic particles (SEPs) can lead to the production of odd nitrogen, nitrate spikes in ice cores have been tentatively used to docum

Sources of elemental carbon (EC) and organic carbon (OC) in atmospheric aerosols (carbonaceous aerosols) were investigated by collection of weekly aerosol filter samples at six background sites in Northern Europe (Birkenes, Norway; Vavihill, Sweden; Risoe, Denmark; Cabauw and Rotterdam in The Netherlands; Melpitz, Germany) during winter 2013. Analysis of 14C and a set of molecular tracers were use

The pre-industrial millennium is among the periods selected by the Paleoclimate Model Intercomparison Project (PMIP) for experiments contributing to the sixth phase of the Coupled Model Intercomparison Project (CMIP6) and the fourth phase of the PMIP (PMIP4). The past1000 transient simulations serve to investigate the response to (mainly) natural forcing under background conditions not too differe

Anthropogenic emissions and land use changes have modified atmospheric aerosol concentrations and size distributions over time. Understanding preindustrial conditions and changes in organic aerosol due to anthropogenic activities is important because these features (1) influence estimates of aerosol radiative forcing and (2) can confound estimates of the historical response of climate to increases

Solar variability has been hypothesized to be a major driver of North Atlantic millennial-scale climate variations through the Holocene along with orbitally induced insolation change. However, another important climate driver, volcanic forcing has generally been underestimated prior to the past 2,500 years partly owing to the lack of proper proxy temperature records. Here, we reconstruct seasonall

In ubiquitous computing, end-user composition allows users to combine multiple single-purpose devices into new, interesting constellations. In PalCom – a ubiquitous middleware – this is achieved without the need to write program code. In this paper we present a solution that in the same way allows users to create Graphical User Interfaces (GUIs) for such systems without coding. The approach is to

Aerosol particles affect Earth’s climate system by scattering and absorbing light. The perturbation of the climate system caused by a change in aerosol configuration due to anthropogenic emissions has recently improved. However, the radiation balance and hydrological cycle of Earth are also highly influenced by clouds: a small change in cloud configuration can have a large effect on the climate. C

In operating systems, resource managers are developed according to simplicity, low overhead, low memory footprint, extensibility and efficiency. Thread schedulers are designed and developed following these implementation-related guidelines. The performance of the implementation is then tested over a set of benchmarks. However, the ability to provide real-time guarantees of these policies is rarely

Although particulate organic and elemental carbon (OC and EC) are important constituents of the suspended atmospheric particulate matter (PM), measurements of OC and EC are much less common and more uncertain than measurements of e.g. the ionic components of PM. In the framework of atmospheric research infrastructures supported by the European Union, actions have been undertaken to determine and m

We consider conditions under which an embedded eigenvalue of a self-adjoint operator remains embedded under small perturbations. In the case of a simple eigenvalue embedded in continuous spectrum of multiplicity m<∞m<∞ we show that in favorable situations, the set of small perturbations of a suitable Banach space which do not remove the eigenvalue form a smooth submanifold of codimension m. We als

Operators on unbounded domains may acquire eigenvalues that are embedded in the essential spectrum. Determining the fate of these embedded eigenvalues under small perturbations of the underlying operator is a challenging task, and the persistence properties of such eigenvalues are linked intimately to the multiplicity of the essential spectrum. In this paper, we consider the planar bilaplacian wit

Aerosol particles exist in the atmosphere in large concentrations and have significant global climate effects. New particle formation is an aerosol particle source and, to date, its contribution to the total aerosol concentration in the atmosphere is not fully understood. This study focuses on the extension of new particle formation events that begin in Lille Valby, Denmark and travel over 70 km t

Various improvements were made to a state-of-the-art aerosol–cloud model and comparison of the model results with observations from field campaigns was performed. The strength of this aerosol–cloud model is in its ability to explicitly resolve all the known modes of heterogeneous cloud droplet activation and ice crystal nucleation. The model links cloud particle activation with the aerosol loading

A Keyless Signing Infrastructure (KSI) provides users with a means to timestamp documents on a per-second basis. The KSI consists of a global infrastructure with several server layers and by using Merkle hash trees, the root hash can be used to verify the integrity and timestamp of a document. Regular publication of root hashes, e.g., once per month, allows a document to be verified without suppor

Today’s multimedia and DSP applications impose requirements on performance and power consumption that only custom processor architectures with SIMD capabilities can satisfy. However, the specific features of such architectures, including vector operations and high-bandwidth complex memory organization, make them notoriously complicated and time consuming to program. In this paper we present an aut

Cloud retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard the satellites Terra and Aqua and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the Suomi-NPP satellite are evaluated using a combination of ground-based instruments providing vertical profiles of clouds. The ground-based measurements are obtained from the Atmospheric Radiat