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Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of inte
Aerosol effects on low-level clouds over the Nordic Countries are investigated by combining in situ ground-based aerosol measurements with remote sensing data of clouds and precipitation. Ten years of number size distribution data from two aerosol measurement stations (Vavihill, Sweden and Hyytiälä, Finland) provide aerosol number concentrations in the atmospheric boundary layer. This is combined
Cloud microphysics is substantially affected by aerosol loading and the resulting changes in the reflective properties of the clouds can significantly affect the global radiation budget. A study of how marine low-level clouds over Barents Sea and the northern parts of the Norwegian Sea are affected by air mass origin has been performed by combining ground-based aerosol measurements with satellite
The Murray Basin is a low-lying but extensive intracratonic depocentre in southeastern Australia, preserving an extraordinary record of Late Neogene sedimentation. New stratigraphic and sedimento-logic data allow the long-term evolution of the basin to be re-evaluated and suggest a significant role for: (1) tectonism in controlling basin evolution, and (2) progressive and step-wise climatic change
We update the forcings for the PMIP3 experiments for the Last Millennium to include new assessments of historical land use changes and discuss new suggestions for calibrating solar activity proxies to total solar irradiance.
Dating of sediment cores from the Baltic Sea has proven to be difficult due to uncertainties surrounding the C-14 reservoir age and a scarcity of macrofossils suitable for dating. Here we present the results of multiple dating methods carried out on cores in the Gotland Deep area of the Baltic Sea. Particular emphasis is placed on the Littorina stage (8 ka ago to the present) of the Baltic Sea and
This paper synthesizes the available scientific information connecting atmospheric nucleation with subsequent cloud condensation nuclei (CCN) formation. We review both observations and model studies related to this topic, and discuss the potential climatic implications. We conclude that CCN production associated with atmospheric nucleation is both frequent and widespread phenomenon in many types o
A short sediment core from a local depression forming an intra basin on the Lomonosov Ridge, was retrieved during the Healy-Oden Trans-Arctic Expedition 2005 (HOTRAX). It contains a record of the Marine Isotope Stages (MIS) 1-3 showing exceptionally high abundances of calcareous microfossils during parts of MIS 3. Based on radiocarbon dating, linear sedimentation rates of 7-9 cm/ka persist during
We have analysed the trends of total aerosol particle number concentrations (N) measured at long-term measurement stations involved either in the Global Atmosphere Watch (GAW) and/or EU infrastructure project ACTRIS. The sites are located in Europe, North America, Antarctica, and on Pacific Ocean islands. The majority of the sites showed clear decreasing trends both in the full-length time series,
Concepts of cognitive radio are yet in an early stage of development. They aim at improving the efficiency of spectrum utilization by exploiting locally and temporally vacant parts of the spectrum. When hierarchical spectrum access is considered, secondary users are authorized to use spectrum white spaces on a non-interfering basis, where minimal impact on the primary systems has to be ensured. GF
Bytecode folding is an effective technique for speeding up execution in Java virtual machines. This paper investigates a hardware implementation of the aforementioned technique on BlueJEP, a Java embedded processor. Since BlueJEP is a micro-programmed stack machine, we adopt a micro-instruction oriented approach, folding up to four microinstructions (corresponding to up to four bytecodes, on occas
We study the well known linear consensus algorithm by means of a LQ-type performance cost. We want to understand how the communication topology influences this algorithm. In order to do this, we recall the analogy between Markov Chains and electrical resistive networks. By exploiting this analogy, we are able to rewrite the performance cost as the average effective resistance on a suitable network
Abstract in UndeterminedFor assembly tasks, the knowledge of both trajectory and forces are usually required. Consequently, we may use kinesthetics or teleoperation for recording human demonstrations. In order to have a more natural interaction, the operator has to be provided with a sense of touch. We propose a bilateral teleoperation system which is customized for this purpose. We introduce diff
We analyze the convergence behavior of iteratively decoded coupled LDPC codes from a complexity point of view. It can be observed that the thresholds of coupled regular LDPC codes approach capacity as the node degrees and the number L of coupled blocks tend to infinity. The absence of degree two variable nodes in these capacity achieving ensembles implies for any fixed L a doubly exponential decre
We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH) of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007). For the wood b
Road safety is one of the most important emerging applications envisioned for Vehicular Ad hoc Networks (VANETs). Generally, such applications involve the broadcast of safety messages, consisting of beacons transmitting vehicles' state (e.g. position and velocity) with a regular period, as well as emergency messages warning about unexpected critical events. From the perspective of safety, the appl
Popular Abstract in Swedish Populärvetenskaplig sammanfattning Hyaluronan (hyaluronsyra) är en högmolekylär polysackarid som förekommer i all biologisk vävnad i olika koncentrationer, med särskilt höga nivåer i bindväv. Den kan bildas av de flesta celltyper. På molekylär nivå föreligger den i form av ett nystan, har förmågan att binda stora mängder vatten, och har en uttalad pseudoplasticitet. HyaHyaluronan has been found in the eye in varying amounts and at different sites. It is involved in physiological and pathological processes, though many aspects of its bio-logi-cal functions are still unclear. We have studied the role of iris tissue in hyal-uro-nan production in the anterior segment of the eye, and its changes after trauma. After peripheral iridectomy or argon laser treatment, the
A novel code construction based on spatially coupled low-density parity-check (SC-LDPC) code chains is presented. The proposed code ensembles are described by graphs in which individual SC-LDPC code chains of various lengths serve as edges. We demonstrate that connecting several appropriately chosen SC-LDPC code chains results in improved iterative decoding thresholds compared to those of a single
