Forcing due to solar and volcanic variability, on the natural side, and greenhouse gas and aerosol emissions, on the anthropogenic side, are the main inputs to climate models. Reliable climate model simulations of past and future climate change depend crucially upon them. Here we analyze large ensembles of simulations using a comprehensive Earth System Model to quantify uncertainties in global climate change attributable to differences in prescribed forcings.
View Article and Find Full Text PDFNonlinear Compton scattering is a promising source of bright gamma rays. Using readily available intense laser pulses to scatter off the energetic electrons, on the one hand, allows us to significantly increase the total photon yield, but on the other hand, leads to a dramatic spectral broadening of the fundamental emission line as well as its harmonics due to the laser pulse shape induced ponderomotive effects. In this Letter we propose to avoid ponderomotive broadening in harmonics by using the polarization gating technique-a well-known method to construct a laser pulse with temporally varying polarization.
View Article and Find Full Text PDFThe COVID-19 (coronavirus disease 2019) pandemic has resulted in a marked slowdown in greenhouse gas and aerosol emissions. Although the resulting emission reductions will continue to evolve, this will presumably be temporary. Here, we provide estimates of the potential effect of such short-term emission reductions on global and regional temperature and precipitation by analyzing the response of an Earth System Model to a range of idealized near-term emission pathways not considered in available model intercomparison projects.
View Article and Find Full Text PDFQuantifying signals and uncertainties in climate models is essential for the detection, attribution, prediction and projection of climate change. Although inter-model agreement is high for large-scale temperature signals, dynamical changes in atmospheric circulation are very uncertain. This leads to low confidence in regional projections, especially for precipitation, over the coming decades.
View Article and Find Full Text PDFScattering of ultraintense short laser pulses off relativistic electrons allows one to generate a large number of X- or gamma-ray photons with the expense of the spectral width-temporal pulsing of the laser inevitable leads to considerable spectral broadening. In this Letter, we describe a simple method to generate optimized laser pulses that compensate the nonlinear spectrum broadening and can be thought of as a superposition of two oppositely linearly chirped pulses delayed with respect to each other. We develop a simple analytical model that allows us to predict the optimal parameters of such a two-pulse-the delay, amount of chirp, and relative phase-for generation of a narrow-band γ-ray spectrum.
View Article and Find Full Text PDFRapid adjustments are responses to forcing agents that cause a perturbation to the top of atmosphere energy budget but are uncoupled to changes in surface warming. Different mechanisms are responsible for these adjustments for a variety of climate drivers. These remain to be quantified in detail.
View Article and Find Full Text PDFIn key European cities, stabilizing climate warming at 1.5 °C would decrease extreme heat-related mortality by 15-22% per summer compared with stabilization at 2 °C.
View Article and Find Full Text PDFGlobally, latent heating associated with a change in precipitation is balanced by changes to atmospheric radiative cooling and sensible heat fluxes. Both components can be altered by climate forcing mechanisms and through climate feedbacks, but the impacts of climate forcing and feedbacks on sensible heat fluxes have received much less attention. Here we show, using a range of climate modelling results, that changes in sensible heat are the dominant contributor to the present global-mean precipitation change since preindustrial time, because the radiative impact of forcings and feedbacks approximately compensate.
View Article and Find Full Text PDFA flexible gamma-ray radiation source based on the resonant laser-plasma wakefield wiggler is proposed. The wiggler is achieved by inducing centroid oscillations of a short laser pulse in a plasma channel. Electrons (self-)injected in such a wakefield experience both oscillations due to the transverse electric fields and energy gain due to the longitudinal electric field.
View Article and Find Full Text PDFA description of the spectral and angular distributions of Compton scattered light in collisions of intense laser pulses with high-energy electrons is unwieldy and usually requires numerical simulations. However, due to the large number of parameters affecting the spectra such numerical investigations can become computationally expensive. Using methods of catastrophe theory we predict higher-dimensional caustics in the spectra of the Compton scattered light, which are associated with bright narrow-band spectral lines, and in the simplest case can be controlled by the value of the linear chirp of the pulse.
View Article and Find Full Text PDFWe investigate the climate response to increased concentrations of black carbon (BC), as part of the Precipitation Driver Response Model Intercomparison Project (PDRMIP). A tenfold increase in BC is simulated by 9 global coupled-climate models, producing a model-median effective radiative forcing (ERF) of 0.82 (ranging from 0.
View Article and Find Full Text PDFStress corrosion cracking (SCC) of metals is an issue of major concern in engineering since this phenomenon causes many catastrophic failures of structural components in aggressive environments. SCC is even more harmful under cathodic conditions promoting the phenomenon known as hydrogen assisted cracking (HAC), hydrogen assisted fracture (HAF) or hydrogen embrittlement (HE). A common way to assess the susceptibility of a given material to HAC, HAF or HE is to subject a cracked rod to a constant extension rate tension (CERT) test until it fractures in this harsh environment.
View Article and Find Full Text PDFAs the global temperature increases with changing climate, precipitation rates and patterns are affected through a wide range of physical mechanisms. The globally averaged intensity of extreme precipitation also changes more rapidly than the globally averaged precipitation rate. While some aspects of the regional variation in precipitation predicted by climate models appear robust, there is still a large degree of inter-model differences unaccounted for.
View Article and Find Full Text PDFPolymorphism and phenotypic diversity of a hostal ecoform of Proteocephalus longicollis from its typical host, the vendace, Coregonus albula L., were studied. A complex phenotypic structure of the parasite population and presence of morphologically different groupings were revealed.
View Article and Find Full Text PDFThe complex dielectric permittivity of salt solutions with positive and negative salvation as well as healthy and cicatricially changed human skin in situ at the frequencies of 42 and 56.6 GHz was measured. The relation between the dielectric characteristics of water and diluted salt solutions and changes in their structural organization conditioned by different temperatures of samples and the type of salvation of electrolytes was studied.
View Article and Find Full Text PDFDiscrete variability of four P. osculatus characteristics descriptive of cestodes' major functional complexes: attachment and trophic-reproduction, was determined. Phenotypic diversity of P.
View Article and Find Full Text PDFThe complex dielectric permitivity of human skin was measured at a frequency of 42 GHz, and a method for calculating water content in skin tissues in vivo was proposed. The water content reaction of skin to standard physical exercises and nontoxic doses of nicotine was investigated. The functionally related changes in skin dielectric properties were interpreted as structural rearrangements of water contained in blood and tissues fluids.
View Article and Find Full Text PDFJ Manipulative Physiol Ther
June 1994
Objective: To evaluate the effectiveness of spinal manipulative therapy (SMT) in the treatment of an internal organ disorder.
Design: Clinical trial.
Setting: Medical hospital.
A study was made of the significance of mononuclear phagocytes in the outcome of post-inflammatory++ peritoneal repair and onset of peritoneal adhesions. It has been revealed that patients with adhesions occurring in the postoperative period manifest insufficiency of the macrophagal response characterized by a decrease of the content of macrophagal elements in peritoneal exudate and derangement of macrophagal migration in the skin fenestra test during reproduction of aseptic inflammation. It is assumed that stimulation of mononuclear phagocytes can serve a means for preventing peritoneal adhesions.
View Article and Find Full Text PDFKhirurgiia (Mosk)
September 1989
Regional hemodynamics in the lower limbs was studied in 250 patients (480 lower limbs) with obliterative lesions of the abdominal aorta and lower limb arteries. Six levels of blood circulation were examined: the iliac segment, the femoral segment, the popliteal and tibial segments, the circulatory channels of the foot and toes. The suggested complex method of ultrasonic measurement of the blood flow in the lower limbs makes it possible to evaluate the hemodynamic significance of the collaterals and the adverse effect of the pathologically changed arterial segment on the regional hemodynamics.
View Article and Find Full Text PDFVestn Khir Im I I Grek
September 1988
A device is proposed for a noninvasive examination of hemodynamics of the aorto-femoral segment which allows to make compression of the arteries under the inguinal ligament. The arterial pressure is measured with an ultrasonic sensor under decompression of the pneumatic balloon. Under examination there were 369 patients.
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