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Despite intense focus on the span classCombining double low lineinline-formulag1/4190/span drop in atmospheric span classCombining double low lineinline-formulaI14C/span during Heinrich Stadial 1 at span classCombining double low lineinline-formulag1/417.4/span-14.6 span classCombining double low lineinline-formulaka/span, the specific mechanisms responsible for the apparent span classCombining do

Sulfur and nitrogen oxides (SOx and NOx) are harmful pollutants emitted into the atmosphere by industry and transport sectors. In addition to being hazardous gases, SOx and NOx form sulfuric and nitric acids which contribute to the formation of airborne particulate matter through nucleation and condensation, hence magnifying the environmental impact of these species. In this work, we build a model

The Sun provides the principal energy input into the Earth system and solar variability represents a significant external climate forcing. Although observations of solar activity (sunspots) cover only the last about 400 years, radionuclides produced by cosmic rays and stored in tree rings or ice cores serve as proxies for solar activity extending back thousands of years. However, the presence of w

Composite adaptive control schemes, which use both the system tracking error and the prediction error to drive the updating law, have become widespread in achieving an improvement of system performance. However, a strong persistent-excitation (PE) condition is required to guarantee the convergence of the parameter estimation errors. This paper proposes a novel composite adaptive control for nonlin

In this paper we address Industrial IoT control applications which are safety-critical and real-time, and which have very low latency and jitter requirements. These control applications are virtualized as software tasks running on a Fog Computing Platform that brings computing and deterministic communication closer to the edge of the network, where the industrial "things" are located. Due to the d

Modern control algorithms are frequently implemented in a distributed and decentralized way. Multiple fog devices communicate using paradigms borrowed from the Internet-of-Things. These control infrastructures are vulnerable to security threats. This position paper describes these threats and sketches future research on how to mitigate the security concerns that a modern distributed control infras

This summary refers to the paper 'Comparison of the FMEA and STPA safety analysis methods-a case study' [Su17]. The paper was published as an article in the Software Quality Journal. It compares the Failure Mode and Effect Analysis (FMEA) and the System Theoretic Process Analysis (STPA) in an industrial case study.

The breakup of the L-chondrite parent body in the asteroid belt 466 million years (Ma) ago still delivers almost a third of all meteorites falling on Earth. Our new extraterrestrial chromite and 3He data for Ordovician sediments show that the breakup took place just at the onset of a major, eustatic sea level fall previously attributed to an Ordovician ice age. Shortly after the breakup, the flux

The performance of HVAC equipment, including chillers, is continuing to be pushed to theoretical limits, which impacts the necessity for advanced control logic to operate them efficiently and robustly. At the same time, their architectures are becoming more complex; many systems have multiple compressors, expansion devices, evaporators, circuits, or other elements that challenge control design and

Between 15 and 27kyrb2k (thousands of years before 2000CE) during the last glacial, Greenland experienced a prolonged cold stadial phase, interrupted by two short-lived warm interstadials. Greenland ice-core calcium data show two periods, preceding the interstadials, of anomalously high atmospheric dust loading, the origin of which is not well understood. At approximately the same time as the Gree

Radiocarbon dating provides a key chronological framework for studying past environmental changes. Raw radiocarbon ages measured in samples must be converted to calendar ages using an appropriate calibration curve. Tree-ring datasets provide the gold-standard for developing a precise curve of atmospheric radiocarbon levels over long-time scales. Here, we reconstruct atmospheric radiocarbon levels

Reliable information on solar activity over the Holocene period is important to predict the Sun in the future and to understand the mechanism behind the Sun-climate linkage. Presently, there are discrepancies in the proxy data of solar activity due to reasons that are not yet understood. This leads to major uncertainties in Holocene solar reconstructions. This PhD project aims to improve the Holoc

Extreme solar particle events (ESPEs) are rare and the most potent known processes of solar eruptive activity. During ESPEs, a vast amount of cosmogenic isotopes (CIs) 10Be, 36Cl, and 14C can be produced in the Earth's atmosphere and deposited in natural stratified archives. Accordingly, CI measurements in these archives allow us to evaluate particle fluxes during ESPEs. In this work, we present a

We present an age model for the 651g€¯m deep ice core from Skytrain Ice Rise, situated inland of the Ronne Ice Shelf, Antarctica. The top 2000 years have previously been dated using age markers interpolated through annual layer counting. Below this, we align the Skytrain core to the AICC2012 age model using tie points in the ice and air phase, and we apply the Paleochrono program to obtain the bes

The IntCal family of radiocarbon (14C) calibration curves is based on research spanning more than three decades. The IntCal group have collated the 14C and calendar age data (mostly derived from primary publications with other types of data and meta-data) and, since 2010, made them available for other sorts of analysis through an open-access database. This has ensured transparency in terms of the

Volcanic eruptions are documented throughout geological history and are frequently observed and experienced in the modernworld. Strong eruptions in recent decades have resulted in air and water pollution, acid snowfall, disruption in aerial transport and variousillnesses in humans and livestock. Despite their consequences, these recent events are incomparable to eruptions of a much largermagnitude

Based on an ethnographic survey of the 26th Conference of the United Nations Framework Convention on Climate Change, this article analyses the ways in which youth participate in climate negotiations. We show how youth actors are characterised by diverse modes of engagement, and particular sociodemographic anchors. Presenting themselves as the voice of youth worldwide, youth actors have gradually c

Multi-archive studies of climate events and archive-specific response times require synchronous time scales. Aligning common variations in the cosmogenic radionuclide production rate via curve fitting methods provides a tool for the continuous synchronization of natural environmental archives down to decadal precision. Based on this approach, we synchronize 10Be records from Western Gotland Basin

Galactic cosmic rays (GCRs) interact with the Earth’s atmosphere to produce energetic neutrons and cosmogenic radionuclides, such as 14C. The atmosphere is partially shielded from the interstellar GCR spectrum by both the geomagnetic and solar magnetic fields. Solar shielding is often expressed as the heliospheric modulation potential ϕ, which consolidates information about the strength and struct

10Be is produced by the interaction between galactic cosmic rays (GCRs) and solar energetic particles (SEPs) with the Earth's atmospheric constituents. The flux of GCRs is modulated by the varying strength of the magnetic fields of the Earth and the Sun. Measurement of 10Be concentrations from polar ice cores is thus a valuable tool to reconstruct the variations in the geomagnetic field and solar