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[en] Designing some long-lasting industrial assets necessitates an estimation of far future extremes. Extreme value estimation is commonly based on an application of the statistical extreme value theory (EVT), which requires that the studied variable is independent and identically distributed, or, at least, stationary. Climate variables exhibit different behaviors which potentially violate this assumption: Seasonality is generally the easiest to handle, and interannual variability is more complicated. Now, as far as temperature is concerned, an additional source of non-stationarity appears: the warming trend, whose interactions with interannual variability add another range of complexity. The approach proposed here is based on the construction of a standardized variable, whose extremes can be considered as stationary. This allows an application of EVT in better accordance with its assumptions. Recent works (Parey et al. in J Geophys Res Atmos 118:8285–8296, 2013. https://doi.org/10.1002/jgrd.50629 ) have shown that if optimized smooth trends in mean and standard deviation are removed from the temperature time series, then the extremes of the residuals can be considered as stationary. A statistical test has been designed to check this assumption. Here, the inference of high-temperature extremes from the extremes of this standardized variable and future mean and standard deviation projected at the desired time horizon, and given by climate model simulations, is further analyzed and justified.
[en] In recent years, climate change has been one of the most complicated problems that human being has faced. Climate change adaptation (CCA) is considered to be an important component of risk management. In order to achieve adaptation, it is necessary to determine the indicators influencing adaptation in each community and this requires measurement and standard tools. The aim of this study is to determine and categorize the indicators of CCA. International electronic databases including Science Direct, Web of Science, Scopus, Google Scholar were investigated for only articles published in English language. In addition, Iranian databases including Irandoc, SID, and Magiran were investigated. There was no limitation on the methods of studies. Furthermore, snowball method was used for finding more articles while the ProQuest database was searched for related dissertations. The published documents from 1990 to November 2017 were gathered in this study. Out of 4439 publications initially search, 152 full texts were investigated. Finally, a total of 45 potentially relevant citations were included for full text review; in addition, fourteen other sources were investigated. Using snowball method, we found 24 other articles that were included in our final result. From the searches, 176 indicators were identified, while seven main domains were mentioned. Since in the articles, domains of adaptation are not in the form of a model, it is better to focus on this issue in the future and it seems that prioritizing and weighting domains in adaptation in different communities with different needs are an important issue.
[en] The paper discusses temporal changes in the configuration of vertical climatic belts in the Tatra Mountains as a result of current climate change. Meteorological stations are scarce in the Tatra Mountains; therefore, we modelled decadal air temperatures using existing data from 20 meteorological stations and the relationship between air temperature and altitude. Air temperature was modelled separately for northern and southern slopes and for convex and concave landforms. Decadal air temperatures were additionally used to delineate five climatic belts previously distinguished by Hess on the basis of threshold values of annual air temperature. The spatial extent and location of the borderline isotherms of 6, 4, 2, 0, and − 2 °C for four decades, including 1951–1960, 1981–1990, 1991–2000, and 2001–2010, were compared.Significant warming in the Tatra Mountains, uniform in the vertical profile, started at the beginning of the 1980s and led to clear changes in the extent and location of the vertical climatic belts delineated on the basis of annual air temperature. The uphill shift of the borderline isotherms was more prominent on southern than on northern slopes. The highest rate of changes in the extent of the climatic belts was found above the isotherm of 0 °C (moderately cold and cold belts). The cold belt dramatically diminished in extent over the research period.
[en] As part of a research project in the Máster en Innovación Tecnológica en Edificación (UPM), an adaption of a simple building to a new location was carried out, coherently using advanced passive systems. The case study was the Farnsworth House, designed by L. Mies van der Rohe and built between 1945 and 1951. The building is a volume of pure forms, with a steel structure closed with a glass façade, without natural ventilation except for the main door. Despite being an icon of the international movement, the Farnsworth House is a problematic building in what comes to its relationship with climate. The location proposed is a plot 234 meters above sea level, in the municipality of Porto Nacional, Tocantins, Brazil. The type of climate in this area is Tropical Dry, according to the Köppen classification.   The site is relatively flat; It is located east of the Tocantins River, with an important plant mass on its west side. This condition generates high levels of humidity despite being a theoretically dry site. All these conditions, as well as the annual climatic data, are decisive for the design and adaptation to the new location. Once the climate was studied it could be noted that ventilation allowed counteracting both the high temperatures and the humidity of the area, providing a greater integral feeling of well-being. In addition, a strategy to guarantee that high external temperatures did not reach the interior of the building seemed necessary, requiring shadow elements to avoid thermal gains -but still provide indirect natural lighting. At the same time, it seemed important to use materials with high thermal inertia and to modify the roofs, since the site is one with a large rainy season Simulations with the Star CCM+ software were performed to evaluate the building, both in its current state and under the proposed design. A drastic improvement in air movement could be verified, proving the suitability of the strategies implemented for adequate natural ventilation. In addition, the solar path was simulated, verifying the operation of the designed eaves and the direct incidence of sunlight inside the building. This research shows that architecture must adapt to a specific latitude and to a particular site, with its topography, vegetation and water masses, its materials and its surroundings. Simple designs are not easily adaptable to any environment, so architects must take into account all the aspects around them. Several digital tools exist nowadays that allow verifying the adequacy of every environmental adaptation, making it possible to determine, before construction, if the proposed constructive solution really solves the identified problem
[en] The global temperature series is a major indicator of climate change, whereas this indicator has undergone shift in trend over the twentieth century, changing from linear trend to nonlinear trend as a result of structural breaks. This paper investigates global and regional sea surface (SS) and land air surface (LS) temperature series from 1880 to 2016 by means of fractional integration technique. The results show that temperature series are described by trend stationary process, mostly in long memory range in the case of LS temperature while in the case of SS temperature, temperature series are in nonstationary mean reverting range for global and hemispheric temperature as well as for three other regional locations. By applying the multiple structural break test, the trend line is found breaking in many dates, locking up into many regimes which can be described using nonlinear trend structure. Nonlinear trend, based on Chebyshev inequality in the fractional integration framework, shows that global and regional temperature series can be represented using nonlinear trend up to the third order since this further lowers the integration order to long memory range in both SS and LS temperature series.
[en] This study investigated the variation of extreme precipitation on a catchment under climate change. Extreme value analysis using generalized extreme value distribution was used to characterize the extreme precipitation. Reliability ensemble average of annual maximum precipitation projections of five global climate model–regional climate model (GCM–RCM) combinations was used to analyse the precipitation extremes under the representative concentration pathways, RCPs 4.5 and 8.5. In order to tackle the nonstationarity present in the bias-corrected ensemble-averaged annual maximum precipitation series under RCPs 4.5 and 8.5, it was split in such a way that the resulting blocks were stationary. Here the analysis was performed for three blocks 2010–2039, 2040–2069 and 2070–2099, each of which were individually stationary. Uncertainty analysis was done to estimate the ranges of extreme precipitation corresponding to return periods of 10, 25 and 50 years. Results of the study indicate that the extreme precipitation corresponding to these return periods in the three time blocks under the RCPs 4.5 and 8.5 exhibit an increasing trend. Extreme precipitation for these return periods are obtained as higher for the RCP scenarios compared to that obtained using observations. Also the extreme precipitation under RCP8.5 is higher compared to that under RCP4.5 scenario.
[en] Faced with the danger of global warming, many countries engaged in the energy transition have instituted a carbon tax or are preparing to do so. The best known example is Sweden, where a carbon tax was introduced as early as 1991. After gradual increases, the tax reached a high level in 2018 (125 Euros/tonne of carbon), which is supported by the whole political field, social partners and the population
[fr]Face au peril du rechauffement climatique, de nombreux pays engages dans la transition energetique ont institue une taxe carbone ou s'appretent a le faire. L'exemple le plus connu est celui de la Suede, ou une taxe carbone a ete mise en place des 1991. Apres des augmentations progressives, la taxe a atteint en 2018 un niveau eleve (125 Euros/tonne de carbone), qui recueille l'adhesion de l'ensemble du champ politique, des partenaires sociaux et de la population
[en] During recent years, various studies have focused on investigating the direct and indirect impacts of climate changes in Iran while the noteworthy fact is the achievement gained by these researches. Furthermore, what should be taken into consideration is whether these studies have been able to provide appropriate opportunities for improving further studies in this particular field or not. To address these questions, this study systematically reviewed and summarized the current available literature (n = 150) regarding the impacts of climate change on temperature and precipitation in Iran to assess our current state of knowledge. The results revealed that while all studies discuss the probable changes in temperature and precipitation over the next decades, serious contradictions could be seen in their results; also, the general pattern of changes was different in most of the cases. This matter may have a significant effect on public beliefs in climate change, which can be a serious warning for the activists in this realm.
[en] Climate change is a real phenomenon with proven evidence, it represents the biggest challenge humanity is facing . In light of this issue, architecture should be able to adapt in order to guarantee hygrothermal comfort of people inside buildings, in the context of an increasingly warmer planet. If the climate changes, architecture should too. This investigation´s overall purpose is to achieve hygrothermal comfort of people in the context of climate change in Costa Rica, by adapting selected buildings to two different scenarios, using projected data and simulation software. This project is based on the thesis of Arch. Andrea Sancho  which is about performance based design. Climate change will affect the national territory entirely. However, it’s necessary to identify the most vulnerable study zone by doing a three-layer analysis: ecological , demographic  and economic  . After the definition of the study zone, possible buildings to study are listed and selected through a series of evaluation criteria such as: location, type, useful life, etc. A bioclimatic analysis was done for every zone and building selected. In the macro scale, annual weather data as well as geographical data are analyzed, with the purpose of determining the different comfort ranges for each region. In the meso scale, a building analysis is done, taking into consideration its immediate environment; Also, an hourly weather data file is created for each region using data provided by the National Weather Institute of Costa Rica (IMN) in order to do a first simulation. In the micro scale, a comparison between the inside and the outside temperature is done, to evaluate the performance of the envelope through long term measurements...
[en] Sparse gauge networks in Sub-Saharan Africa (SSA) limit our ability to identify changing precipitation extremes with in situ observations. Given the potential for satellite and satellite-gauge precipitation products to help, we investigate how daily gridded gauge and satellite products compare for seven core climate change precipitation indices. According to a new gauge-only product, the Rainfall Estimates on a Gridded Network (REGEN), there were notable changes in SSA precipitation characteristics between 1950 and 2013 in well-gauged areas. We examine these trends and how these vary for wet, intermediate, and dry areas. For a 31 year period of overlap, we compare REGEN data, other gridded products and three satellite products. Then for 1998–2013, we compare a set of 12 satellite products. Finally, we compare spatial patterns of 1983–2013 trends across all of SSA. Robust 1950–2013 trends indicate that in well-gauged areas extreme events became wetter, particularly in wet areas. Annual totals decreased due to fewer rain days. Between 1983 and 2013 there were positive trends in average precipitation intensity and annual maximum 1 d totals. These trends only represent 15% of SSA, however, and only one tenth of the main wet areas. Unfortunately, gauge and satellite products do not provide consensus for wet area trends. A promising result for identifying regional changes is that numerous satellite products do well at interannual variations in precipitation totals and number of rain days, even as well as some gauge-only products. Products are less accurate for dry spell length and average intensity and least accurate for annual maximum 1 d totals. Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (3B42-V7) and Climate Hazards center Infrared Precipitation with Stations (CHIRPS v2.0) ranked highest for multiple indices. Several products have seemingly unrealistic trends outside of the well-gauged areas that may be due to influence of non-stationary systematic biases. Social media abstract. Sparse data show increasing Africa rainfall extremes and satellite products fill some missing pieces. (letter)