The Cyprus Institute

About: The Cyprus Institute is a other organization based out in Nicosia, Cyprus. It is known for research contribution in the topics: Aerosol & Environmental science. The organization has 418 authors who have published 1252 publications receiving 32586 citations.

Disease burden and excess mortality from coal-fired power plant emissions in Europe

Abstract: We studied the contribution of coal-fired power plant (CPP) emissions (SO2 and NOx) to air pollution levels and annual excess mortality by cardiovascular and respiratory diseases in Europe, based on fine particulate matter (PM2.5) concentrations computed with a regional atmospheric chemistry-transport model. The health burden of European CPP emission-induced PM2.5, estimated with the Global Exposure Mortality Model, amounts to at least 16 800 (CI95 14 800–18 700) excess deaths per year over the European domain. We identified an underestimation of the emissions magnitude and correcting for it doubles CPP-attributed annual excess mortality to 33 900 (CI95 33 000–37 600) per year. Due to the non-linearity of exposure-responses, especially at relatively low concentrations, these estimates represent lower limits of possible health benefits for the EU-28 states. CPP emission phase-out would avoid 18 400 (CI95 16 000–20 500) excess deaths annually assuming background PM2.5 levels of 10 µg m−3, 25 500 (CI95 22 600–28 200) per year if pollution levels from other sources are reduced by 50% in parallel, and 105 900 (CI95 89 900–121 700) deaths by drastically reducing anthropogenic pollution from other sources to 2.4 µg m−3 that represents the threshold for health impacts. Depending on the emission scenario, large health gains can be achieved from the phase-out of CPP emissions, which calls for coordinated air pollution control strategies at the European level.

Sources and processes that control the submicron organic aerosol in an urban Mediterranean environment (Athens) using high temporal resolution chemical composition measurements

Abstract: . Submicron aerosol chemical composition has been studied during a year-long period (26/07/2016–31/07/2017) and two winter-time intensive campaigns (18/12/2013–21/02/2014 and 23/12/2015–17/02/2016), at a central site in Athens, Greece, using an Aerosol Chemical Speciation Monitor (ACSM). Concurrent measurements include a Particle-Into-Liquid Sampler (PILS-IC), a Scanning Mobility Particle Sizer (SMPS), an AE-33 Aethalometer and Ion Chromatography analysis on 24 or 12 hour filter samples. Quality of the ACSM data was assured by comparison versus the above mentioned measurements. The aim of the study was to characterize the seasonal variability of the main fine aerosol constituents and decipher the sources of organic aerosol (OA). Organics were found to contribute almost half of the submicron mass, with concentrations during wintertime reaching up to 200 μg m −3 , on occasions. During this season, the primary sources contribute about 34 % of the organic fraction, comprising of biomass burning (10 %), fossil fuel combustion (16 %) and cooking (8 %), while the remaining 66 % is attributed to secondary aerosol. The semi-volatile component of the oxidized organic aerosol (SV-OOA; 31 %) was found to be clearly linked to combustion sources and in particular biomass burning, and even a part of the very oxidized, low-volatility component (LV-OOA; 35 %) could also be attributed to the oxidation of emissions from these primary combustion sources. These results highlight the rising importance of biomass burning in urban environments during wintertime, as revealed through this characteristic example of Athens, Greece, where the economic recessions led to an abrupt shift to biomass burning for heating purposes in winter. During summer, when concentrations of fine aerosols are considerably lower, more than 80 % of the organic fraction is attributed to secondary aerosol (SV-OOA 30 % and LV-OOA 53 %). In contrast to winter, SV-OOA appears to result from a well-mixed type of aerosol, linked to fast photochemical processes and the oxidation of primary traffic and biogenic emissions. Finally, LV-OOA presents a more regional character in summer, owing to the oxidation, within a few days, of organic aerosol.

Global Risk from the Atmospheric Dispersion of Radionuclides by Nuclear Power Plant Accidents in the Coming Decades

Abstract: We estimate the global risk from the release and atmospheric dispersion of radionuclides from nuclear power plant accidents using the EMAC atmospheric chemistry–general circulation model We included all nuclear reactors that are currently operational, under construction and planned or proposed We implemented constant continuous emissions from each location in the model and simulated atmospheric transport and removal via dry and wet deposition processes over 20 years (2010–2030), driven by boundary conditions based on the IPCC A2 future emissions scenario We present global overall and seasonal risk maps for potential surface layer concentrations and ground deposition of radionuclides, and estimate potential doses to humans from inhalation and ground-deposition exposures to radionuclides We find that the risk of harmful doses due to inhalation is typically highest in the Northern Hemisphere during boreal winter, due to relatively shallow boundary layer development and limited mixing Based on the continued operation of the current nuclear power plants, we calculate that the risk of radioactive contamination to the citizens of the USA will remain to be highest worldwide, followed by India and France By including stations under construction and those that are planned and proposed, our results suggest that the risk will become highest in China, followed by India and the USA

The critical temperature of the 2D-Ising model through Deep Learning Autoencoders

Abstract: We investigate deep learning autoencoders for the unsupervised recognition of phase transitions in physical systems formulated on a lattice. We focus our investigation on the 2-dimensional ferromagnetic Ising model and then test the application of the autoencoder on the anti-ferromagnetic Ising model. We use spin configurations produced for the 2-dimensional ferromagnetic and anti-ferromagnetic Ising model in zero external magnetic field. For the ferromagnetic Ising model, we study numerically the relation between one latent variable extracted from the autoencoder to the critical temperature $T_c$. The proposed autoencoder reveals the two phases, one for which the spins are ordered and the other for which spins are disordered, reflecting the restoration of the $\mathbb{Z}_2$ symmetry as the temperature increases. We provide a finite volume analysis for a sequence of increasing lattice sizes. For the largest volume studied, the transition between the two phases occurs very close to the theoretically extracted critical temperature. We define as a quasi-order parameter the absolute average latent variable ${\tilde z}$, which enables us to predict the critical temperature. One can define a latent susceptibility and use it to quantify the value of the critical temperature $T_c(L)$ at different lattice sizes and that these values suffer from only small finite scaling effects. We demonstrate that $T_c(L)$ extrapolates to the known theoretical value as $L \to \infty$ suggesting that the autoencoder can also be used to extract the critical temperature of the phase transition to an adequate precision. Subsequently, we test the application of the autoencoder on the anti-ferromagnetic Ising model, demonstrating that the proposed network can detect the phase transition successfully in a similar way.

Aerosol water parameterization: long-term evaluation and importance for climate studies

Abstract: . We scrutinize the importance of aerosol water for the aerosol optical depth (AOD) calculations using a long-term evaluation of the EQuilibrium Simplified Aerosol Model v4 for climate modeling. EQSAM4clim is based on a single solute coefficient approach that efficiently parameterizes hygroscopic growth, accounting for aerosol water uptake from the deliquescence relative humidity up to supersaturation. EQSAM4clim extends the single solute coefficient approach to treat water uptake of multicomponent mixtures. The gas–aerosol partitioning and the mixed-solution water uptake can be solved analytically, preventing the need for iterations, which is computationally efficient. EQSAM4clim has been implemented in the global chemistry climate model EMAC and compared to ISORROPIA II on climate timescales. Our global modeling results show that (I) our EMAC results of the AOD are comparable to modeling results that have been independently evaluated for the period 2000–2010, (II) the results of various aerosol properties of EQSAM4clim and ISORROPIA II are similar and in agreement with AERONET and EMEP observations for the period 2000–2013, and (III) the underlying assumptions on the aerosol water uptake limitations are important for derived AOD calculations. Sensitivity studies of different levels of chemical aging and associated water uptake show larger effects on AOD calculations for the year 2005 compared to the differences associated with the application of the two gas–liquid–solid partitioning schemes. Overall, our study demonstrates the importance of aerosol water for climate studies.