Cyprus Institute

Nicosia, Cyprus

Cyprus Institute

Nicosia, Cyprus
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Santamouris M.,National and Kapodistrian University of Athens | Santamouris M.,Cyprus Institute
Energy and Buildings | Year: 2014

Urban heat island and global warming increase ambient temperature and modify the energy budget of buildings. The magnitude of the modification has been evaluated in a large number of articles, under different climatic and building boundary conditions. This paper collects, analyzes and classifies existing knowledge regarding the energy impact of urban heating to buildings and calculates preliminary indicators and impact figures. Based on the analysis of the impact studies, it is found that in average the cooling load of typical urban buildings is by 13% higher compared to similar buildings in rural areas. Four specific energy impact indicators, the global energy penalty per m2, the global energy penalty per m2 and degree of UHI, the global energy penalty per person and the global energy penalty per person and per degree of the UHI are defined and calculated. The variability of the heating and cooling loads of typical buildings is evaluated for the period 1970-2010. The average increase of the cooling demand is 23% while the corresponding average reduction of the heating is 19%. In total, the average energy consumption of typical buildings for heating and cooling purposes increased by 11% for the same period. © 2014 Elsevier B.V.

News Article | November 28, 2016

Australia's solar heliostat technology will be used for concentrating solar thermal (CST) electricity generation in China.In continued emphasis on mitigation and adaptation, CSIRO has partnered with Chinese company Thermal Focus, following China's announcement to produce 1.4 GW of CST by 2018, and 5 GW by 2020. This would double the world's installed CST plants. The relationship enables Thermal Focus to manufacture, market, sell and install CSIRO's patented low cost heliostats, field control software and design software in China, with a shared revenue stream back to Australia to fund further climate mitigation research.CSIRO Chief Executive Dr Larry Marshall said he was proud of CSIRO Energy's solar thermal technology team and their innovative science for the contribution it is making to support Australia's mitigation R&D. "Australia is a leader in clean energy technology and CSIRO's partnership with China's Thermal Focus takes our climate mitigation focus to a global stage," Dr Marshall said. "This is another great example of all four pillars of our Strategy 2020 in action; using excellent science to deliver breakthrough innovation, and through global collaboration, increasing renewable energy deliverables. "Through this collaboration and our continued solar research, we will be helping to generate cleaner energy, cost savings and technology export benefits for Australia; all lowering global greenhouse gas emissions." Solar thermal technology uses a field of computer-controlled mirrors (heliostats) that accurately reflect and concentrate sunlight onto a receiver on top of a tower. The concentrated sunlight may then be used to heat and store hot molten salt, which can generate superheated steam to drive a turbine for electricity generation. An advantage of this system is the very low cost of storing thermal energy, giving CST technology great potential for medium to large-scale solar power, even when the sun isn't shining. A heliostat field can represent up to 40 per cent of the total plant cost so low cost, high precision heliostats are a crucial component. CSIRO's unique design features smaller than conventional heliostats, and uses an advanced control system to get high performance from a cost-effective design. CSIRO's software optimises the configuration of the heliostats prior to construction and manages each heliostat to ensure the optimum amount of reflected heat is focused on the receiver, maximising the amount of power that can be produced. The licensing agreement with Thermal Focus follows CSIRO's successful international solar thermal partnerships with Japan's Mitsubishi Hitachi Power Systems, and the Cyprus Institute and Heliostat SA in Australia. Mr Wei Zhu from Thermal Focus, welcomes the collaboration and acknowledges CSIRO's reputation in R&D and work in solar thermal research. "CSIRO's solar thermal technology combined with our manufacturing capability will help expedite and deliver solar thermal as an important source of renewable energy in China," Mr Zhu said. "This partnership will help us commercialise this emerging technology on a larger scale." The licensing agreement with China's Thermal Focus is being announced today at the Asia-Pacific Solar Research Conference at the Australian National University.

Lelieveld J.,Max Planck Institute for Chemistry | Lelieveld J.,Cyprus Institute | Evans J.S.,Harvard University | Evans J.S.,Cyprus University of Technology | And 3 more authors.
Nature | Year: 2015

Assessment of the global burden of disease is based on epidemiological cohort studies that connect premature mortality to a wide range of causes, including the long-term health impacts of ozone and fine particulate matter with a diameter smaller than 2.5 micrometres (PM2.5). It has proved difficult to quantify premature mortality related to air pollution, notably in regions where air quality is not monitored, and also because the toxicity of particles from various sources may vary. Here we use a global atmospheric chemistry model to investigate the link between premature mortality and seven emission source categories in urban and rural environments. In accord with the global burden of disease for 2010 (ref. 5), we calculate that outdoor air pollution, mostly by PM2.5, leads to 3.3 (95 per cent confidence interval 1.61-4.81) million premature deaths per year worldwide, predominantly in Asia. We primarily assume that all particles are equally toxic, but also include a sensitivity study that accounts for differential toxicity. We find that emissions from residential energy use such as heating and cooking, prevalent in India and China, have the largest impact on premature mortality globally, being even more dominant if carbonaceous particles are assumed to be most toxic. Whereas in much of the USA and in a few other countries emissions from traffic and power generation are important, in eastern USA, Europe, Russia and East Asia agricultural emissions make the largest relative contribution to PM2.5, with the estimate of overall health impact depending on assumptions regarding particle toxicity. Model projections based on a business-as-usual emission scenario indicate that the contribution of outdoor air pollution to premature mortality could double by 2050. ©2015 Macmillan Publishers Limited. All rights reserved.

De Arellano J.V.-G.,Wageningen University | Van Heerwaarden C.C.,Max Planck Institute for Meteorology | Lelieveld J.,Max Planck Institute for Chemistry | Lelieveld J.,Cyprus Institute
Nature Geoscience | Year: 2012

Cumulus clouds in the atmospheric boundary layer play a key role in the hydrologic cycle, in the onset of severe weather by thunderstorms and in modulating Earth's reflectivity and climate. How these clouds respond to climate change, in particular over land, and how they interact with the carbon cycle are poorly understood. It is expected that as a consequence of rising atmospheric CO 2 concentrations the plant stomata will close, leading to lower latent heat fluxes and higher sensible heat fluxes. Here we show that this causes a decline in boundary-layer cloud formation in middle latitudes. This could be partly counteracted by the greater ability of a warmer atmosphere to take up water and by a growth in biomass due to CO 2 fertilization. Our results are based on a new soil-water-atmosphere-plant model supported by comprehensive observational evidence, from which we identify the dominant atmospheric responses to plant physiological processes. They emphasize the intricate connection between biological and physical aspects of the climate system and the relevance of short-term and small-scale processes in establishing this connection.

Alexandrou C.,University of Cyprus | Alexandrou C.,Cyprus Institute
EPJ Web of Conferences | Year: 2014

We present recent developments in lattice QCD simulations as applied in the study of hadron structure. We discuss the challenges and perspectives in the evaluation of benchmark quantities such as the nucleon axial charge and the isovector parton momentum fraction, as well as, in the computation of the nucleon σ-terms, which involve the calculation of disconnected quark loop contributions. © Owned by the authors, published by EDP Sciences, 2014.

Alexandrou C.,University of Cyprus | Alexandrou C.,Cyprus Institute
Progress in Particle and Nuclear Physics | Year: 2012

Recent progress in hadron structure calculations within lattice QCD is reviewed. Results on key observables such as the axial charge, the quark momentum fraction and the spin content of the nucleon are discussed with focus on open issues. Lattice QCD studies of the γ*N→Δ transition as well as the Δ form factors are also presented. © 2012 Elsevier B.V. All rights reserved.

News Article | June 22, 2016

In the event of a severe drought, which animals would do quite well and which ones will falter? A new theoretical framework may be able to answer these questions, as researchers from James Cook University in Australia produced a template that measures animal physiology, environment, and other factors that could determine how a given species would deal with extreme droughts. Lead researcher Tasmin Rymer said more frequent and worse droughts will hit many areas as the current rate of climate change becomes unprecedented in the planet’s history. Her team then developed a model that will help researchers estimate the probability of a species coping with such climate events. Dubbed the “Adaptive Triquetra” model, it factors in the main driving stressors of droughts, namely limited water, temperature and reduced food availability. Afterwards, it looks at the ability of a creature’s particular body system to mount a response — and how much its traits prove adaptable. “We have provided a comprehensive suite of traits to consider when making predictions about species’ resilience to drought,” Rymer said, adding that the process is more intricate than it appears and requires fully determining many species’ characteristics before the model can be used on them. While still a conceptual framework needing to be tested, the Adaptive Triquetra is touted useful in managing wildlife. South African reserve managers, for instance, may assume their animals’ suffering roots from lack of water during a drought. The reality could be that the vegetation surrounding their few artificial water holes have already been denuded, leading the poor ones to starve. The new model, explained Rymer, could suggest a sustainable design that promotes movement and foraging in a bigger area, mainly through doing away with fences and optimally spacing water sources apart. Species hit by water stress can be assisted with more artificial water sources, while those vulnerable to high temperatures could be given subterranean homes. The findings were published in The Quarterly Review of Biology. In May, researchers from the Cyprus Institute and the Max Planck Institute for Chemistry warned that climate change could cause the Middle East and North Africa to become unlivable by 2050, with rapid and frequent temperature rise and air pollution from dust storms leading more than 500 million people to migrate. Long periods of drought, they added, caused sandstorms that had led to increased atmospheric desert dust in countries like Saudi Arabia, Iraq and Syria. © 2016 Tech Times, All rights reserved. Do not reproduce without permission.

Lawrence M.G.,Max Planck Institute for Chemistry | Lawrence M.G.,University of Mainz | Lelieveld J.,Max Planck Institute for Chemistry | Lelieveld J.,Cyprus Institute
Atmospheric Chemistry and Physics | Year: 2010

Southern Asia, extending from Pakistan and Afghanistan to Indonesia and Papua New Guinea, is one of the most heavily populated regions of the world. Biofuel and biomass burning play a disproportionately large role in the emissions of most key pollutant gases and aerosols there, in contrast to much of the rest of the Northern Hemisphere, where fossil fuel burning and industrial processes tend to dominate. This results in polluted air masses which are enriched in carbon-containing aerosols, carbon monoxide, and hydrocarbons. The outflow and long-distance transport of these polluted air masses is characterized by three distinct seasonal circulation patterns: the winter monsoon, the summer monsoon, and the monsoon transition periods. During winter, the near-surface flow is mostly northeasterly, and the regional pollution forms a thick haze layer in the lower troposphere which spreads out over millions of square km between southern Asia and the Intertropical Convergence Zone (ITCZ), located several degrees south of the equator over the Indian Ocean during this period. During summer, the heavy monsoon rains effectively remove soluble gases and aerosols. Less soluble species, on the other hand, are lifted to the upper troposphere in deep convective clouds, and are then transported away from the region by strong upper tropospheric winds, particularly towards northern Africa and the Mediterranean in the tropical easterly jet. Part of the pollution can reach the tropical tropopause layer, the gateway to the stratosphere. During the monsoon transition periods, the flow across the Indian Ocean is primarily zonal, and strong pollution plumes originating from both southeastern Asia and from Africa spread across the central Indian Ocean. This paper provides a review of the current state of knowledge based on the many observational and modeling studies over the last decades that have examined the southern Asian atmospheric pollutant outflow and its large scale effects. An outlook is provided as a guideline for future research, pointing out particularly critical issues such as: resolving discrepancies between top down and bottom up emissions estimates; assessing the processing and aging of the pollutant outflow; developing a better understanding of the observed elevated pollutant layers and their relationship to local sea breeze and large scale monsoon circulations; and determining the impacts of the pollutant outflow on the Asian monsoon meteorology and the regional hydrological cycle, in particular the mountain cryospheric reservoirs and the fresh water supply, which in turn directly impact the lives of over a billion inhabitants of southern Asia. © Author(s) 2010.

Christoudias T.,Cyprus Institute | Lelieveld J.,Cyprus Institute | Lelieveld J.,Max Planck Institute for Chemistry
Atmospheric Chemistry and Physics | Year: 2013

We modeled the global atmospheric dispersion and deposition of radionuclides released from the Fukushima Dai-ichi nuclear power plant accident. The EMAC atmospheric chemistry - general circulation model was used, with circulation dynamics nudged towards ERA-Interim reanalysis data. We applied a resolution of approximately 0.5 degrees in latitude and longitude (T255). The model accounts for emissions and transport of the radioactive isotopes 131I and 137Cs, and removal processes through precipitation, particle sedimentation and dry deposition. In addition, we simulated the release of 133Xe, a noble gas that can be regarded as a passive transport tracer of contaminated air. The source terms are based on Chino et al. (2011) and Stohl et al. (2012); especially the emission estimates of 131I are associated with a high degree of uncertainty. The calculated concentrations have been compared to station observations by the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO). We calculated that about 80% of the radioactivity from Fukushima which was released to the atmosphere deposited into the Pacific Ocean. In Japan a large inhabited land area was contaminated by more than 40 kBq m-2. We also estimated the inhalation and 50-year dose by 137Cs, 134Cs and 131I to which the people in Japan are exposed. © Author(s) 2013.

Asproulis N.,Cranfield University | Drikakis D.,Cyprus Institute
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2011

This paper investigates the combined effects of surface stiffness κ and wall particles' mass mw on the slip length. It aims to enhance our understanding of the momentum and energy transfer across solid-liquid interfaces. Elastic spring potentials are employed to simulate the thermal solid walls and model the surface stiffness κ. The thermal oscillation amplitude is primarily dictated by values of stiffness, whereas the oscillating frequency is proportional to √κ/mw. It is shown that for cases with variable wall mass the relation of slip length and thermal oscillating frequencies can be approximated by a "master" curve according to which the length initially increases, then approaches a peak value, and afterwards is reduced toward an asymptotic value. ©2011 American Physical Society.

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