First record of the Indo-Pacific species Iphione muricata Savigny in Lamarck, 1818 (Polychaeta: Iphionidae) from the Mediterranean Sea, Israel

The Indo-Pacific scaleworm Iphione muricata was observed and caught in the Mediterranean Sea along the coast of Israel. Morphological and molecular diagnostic characters of the species are discussed. This is the first record of this alien species in the Mediterranean Sea, and its previous reports in the Suez Canal suggest its introduction via Lessepsian migration

Volcano and ship tracks indicate excessive aerosol-induced cloud water increases in a climate model

Aerosol-cloud interaction is the most uncertain mechanism of anthropogenic radiative forcing of Earth’s climate, and aerosol-induced cloud water changes are particularly poorly constrained in climate models. By combining satellite retrievals of volcano and ship tracks in stratocumulus clouds, we compile a unique observational dataset and confirm that liquid water path (LWP) responses to aerosols are bidirectional, and on average the increases in LWP are closely compensated by the decreases. Moreover, the meteorological parameters controlling the LWP responses are strikingly similar between the volcano and ship tracks. In stark contrast to observations, there are substantial unidirectional increases in LWP in the Hadley Centre climate model, because the model accounts only for the decreased precipitation efficiency and not for the enhanced entrainment drying. If the LWP increases in the model were compensated by the decreases as the observations suggest, its indirect aerosol radiative forcing in stratocumulus regions would decrease by 45%

Implications of longitudinal ridges for the mechanics of ice-free long runout landslides

The emplacement mechanisms of long runout landslides across the Solar System and the formation mechanisms of longitudinal ridges associated with their deposits remain subjects of debate. The similarity of longitudinal ridges in martian long runout landslides and terrestrial landslides emplaced on ice suggests that an icy surface could explain both the reduction of friction associated with the deposition of long runout landslides and the development of longitudinal ridges. However, laboratory experiments on rapid granular flows show that ice is not a necessary requirement for the development of longitudinal ridges, which instead may form from convective cells within high-speed flows. These experiments have shown that the wavelength (S) of the ridges is 2-3 times the thickness (T) of the flow, which has also been demonstrated at field scale on a tens-of-kilometre martian long runout landslide. Here, we present the case study of the 4-km-long, ice-free El Magnifico landslide in Northern Chile which exhibits clear longitudinal ridges, and show for the first time on a terrestrial landslide that the S/T ratio is in agreement with the scaling relationship found for both laboratory rapid granular flows and a previously measured martian long runout landslide. Several outcrops within the landslide allow us to study internal sections of the landslide deposit and their relationship with the longitudinal ridges in order to shed light on the emplacement mechanism. Our observations include interactions without chaotic mixing between different lithologies and the presence of meters-sized blocks that exhibit preserved original bedding discontinuities. We associate these observations with fluctuations in stress, as they are qualitatively similar to numerically modelled rapid granular slides, which were suggested, to some degree, to be associated with acoustic fluidization. Our results suggest that 1) the mechanism responsible for the formation of longitudinal ridges is scale- and environment-independent; 2) while the internal structures observed do not necessarily support a mechanism of convective-style motion, their interpretation could also point to a mechanism of internal deformation of the sliding mass derived from pattern-forming vibrations. Our novel observations and analysis provide important insights for the interpretation of similar features on Earth and Mars and for discerning the underlying mechanisms responsible for the emplacement of long run out landslides

A Versatile and Reproducible Multi-Frequency Electrical Impedance Tomography System

A highly versatile Electrical Impedance Tomography (EIT) system, nicknamed the ScouseTom, has been developed. The system allows control over current amplitude, frequency, number of electrodes, injection protocol and data processing. Current is injected using a Keithley 6221 current source, and voltages are recorded with a 24-bit EEG system with minimum bandwidth of 3.2 kHz. Custom PCBs interface with a PC to control the measurement process, electrode addressing and triggering of external stimuli. The performance of the system was characterised using resistor phantoms to represent human scalp recordings, with an SNR of 77.5 dB, stable across a four hour recording and 20 Hz to 20 kHz. In studies of both haeomorrhage using scalp electrodes, and evoked activity using epicortical electrode mats in rats, it was possible to reconstruct images matching established literature at known areas of onset. Data collected using scalp electrode in humans matched known tissue impedance spectra and was stable over frequency. The experimental procedure is software controlled and is readily adaptable to new paradigms. Where possible, commercial or open-source components were used, to minimise the complexity in reproduction. The hardware designs and software for the system have been released under an open source licence, encouraging contributions and allowing for rapid replication

An automated cirrus classification

Cirrus clouds play an important role in determining the radiation budget of the earth, but many of their properties remain uncertain, particularly their response to aerosol variations and to warming. Part of the reason for this uncertainty is the dependence of cirrus cloud properties on the cloud formation mechanism, which itself is strongly dependent on the local meteorological conditions. In this work, a classification system (Identification and Classification of Cirrus or IC-CIR) is introduced to identify cirrus clouds by the cloud formation mechanism. Using re-analysis and satellite data, cirrus clouds are separated in four main types: orographic, frontal, convective and synoptic. Through a comparison to convection-permitting model simulations and back- trajectory based analysis, it is shown that these observation-based regimes can provide extra information on the cloud scale updraughts and the frequency of occurrence of liquid-origin ice, with the convective regime having higher updraughts and a greater occurrence of liquid-origin ice compared to the synoptic regimes. Despite having different cloud formation mecha- nisms, the radiative properties of the regimes are not distinct, indicating that retrieved cloud properties alone are insufficient to completely describe them. This classification is designed to be easily implemented in GCMs, helping improve future model-observation comparisons and leading to improved parametrisations of cirrus cloud processe

Organization and oscillations in simulated shallow convective clouds

Physical insights into processes governing temporal organization and evolution of cloud fields are of great importance for climate research. Here using large eddy simulations with a bin microphysics scheme, we show that warm convective cloud fields exhibit oscillations with two distinct periods (~10 and ~90 min, for the case studied here). The shorter period dominates the nonprecipitating phase, and the longer period is related to the precipitating phase. We show that rain processes affect the domain\u27s thermodynamics, hence forcing the field into a low‐frequency recharge‐discharge cycle of developing cloudiness followed by precipitation‐driven depletion. The end result of precipitation is stabilization of the lower atmosphere by warming of the cloudy layer (due to latent heat release) and cooling of the subcloud layer (by rain evaporation, creating cold pools). As the thermodynamic instability weakens, so does the cloudiness, and the rain ceases. During the nonprecipitating phase of the cycle, surface fluxes destabilize the boundary layer until the next precipitation cycle. Under conditions that do not allow development of precipitation (e.g., high aerosol loading), high‐frequency oscillations dominate the cloud field. Clouds penetrating the stable inversion layer trigger gravity waves with a typical period of ~10 min. In return, the gravity waves modulate the clouds in the field by modifying the vertical velocity, temperature, and humidity fields. Subsequently, as the polluted nonprecipitating simulations evolve, the thermodynamic instability increases and the cloudy layer deepens until precipitation forms, shifting the oscillations from high to low frequency. The organization of cold pools and the spatial scale related to these oscillations are explored

Universal dynamical decoherence control of noisy single-and multi-qubit systems

In this article we develop, step by step, the framework for universal dynamical control of two-level systems (TLS) or qubits experiencing amplitude- or phase-noise (AN or PN) due to coupling to a thermal bath. A comprehensive arsenal of modulation schemes is introduced and applied to either AN or PN, resulting in completely analogous formulae for the decoherence rates, thus underscoring the unified nature of this universal formalism. We then address the extension of this formalism to multipartite decoherence control, where symmetries are exploited to overcome decoherence.Comment: 28 pages, 4 figure

Impeded Growth of Magnetic Flux Bubbles in the Intermediate State Pattern of Type I Superconductors

Normal state bubble patterns in Type I superconducting Indium and Lead slabs are studied by the high resolution magneto-optical imaging technique. The size of bubbles is found to be almost independent of the long-range interaction between the normal state domains. Under bubble diameter and slab thickness proper scaling, the results gather onto a single master curve. On this basis, in the framework of the "current-loop" model [R.E. Goldstein, D.P. Jackson and A.T. Dorsey, Phys. Rev. Lett. 76, 3818 (1996)], we calculate the equilibrium diameter of an isolated bubble resulting from the competition between the Biot-and-Savart interaction of the Meissner current encircling the bubble and the superconductor-normal interface energy. A good quantitative agreement with the master curve is found over two decades of the magnetic Bond number. The isolation of each bubble in the superconducting matrix and the existence of a positive interface energy are shown to preclude any continuous size variation of the bubbles after their formation, contrary to the prediction of mean-field models.Comment: \'{e}quipe Nanostructures Quantique