A comprehensive review of dryland climates and their relationship to the physical environment, hydrology, and inhabitants. Chapters are divided into five major sections on background meteorology and ...climatology; the nature of dryland climates in relation to precipitation and hydrology; the climatology and climate dynamics of the major dryland regions on each continent; and life and change in the world's drylands. It includes key topics such as vegetation, geomorphology, desertification, micro-habitats, and adaptation to dryland environments. This interdisciplinary volume provides an extensive review of the primary literature (covering nearly 2000 references) and the conventional and satellite datasets that form key research tools for dryland climatology. Illustrated with over 300 author photographs, it presents a unique view of dryland climates for a broad spectrum of researchers, environmental professionals and advanced students in climatology, meteorology, geography, environment science, earth system science, ecology, hydrology and geomorphology.
•PCM can effectively reduce building cooling load in tropical climate.•Selection of phase change temperature, location, thickness, and enthalpy curve of PCM is critical.•Optimum phase change ...temperature is influenced by location, thickness, and enthalpy curve of PCM.•Recommendation on the optimized use of PCM in tropical climate is provided.
Phase change materials (PCMs) are capable to absorb massive heat during a phase transition in a narrow temperature range, which have great potential to be incorporated into building envelopes to prevent heat penetration into buildings and reduce cooling loads. The efficiency and selection of PCMs, however, are highly subject to the climate where they are applied. This study focused on the energy performance of building envelopes integrated with PCMs for cooling load reduction in tropical climate through numerical simulations. Studies were carried out to reveal the efficacy and factors that govern the performance of the PCM addition for cooling load reduction in Singapore. The results showed that PCM can effectively reduce heat gains through building envelopes throughout the whole year, indicating the significant advantage of the use of PCMs in tropics over other regions where PCMs are only effective in certain seasons. The selection of PCM with suitable phase change temperature is critical. PCMs applied to the exterior surfaces of walls showed better performance and the optimum phase change temperature is the lowest temperature allowing the full melting–solidification cycle of the entire PCM layer. A larger phase change temperature range improves the adaptivity of the PCMs to temperature variations, but may compromise the largest energy savings that the PCMs can achieve. While thicker PCM layer reduces heat gains through building envelope, thinner PCM layer shows higher efficiency and cost benefits.
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•A leachate quantification method was established for MSW landfilling.•Water squeezed out of waste is non-negligible for waste with high moisture content.•Leachate generation ...performances differ in various geographic regions in China.•Leachate amounts are significantly lower in northwestern China.•Long-term generation contribute more than 60% in southern China.
The quantity of leachate is crucial when assessing pollution emanating from municipal landfills. In most cases, existing leachate quantification measures only take into account one source – precipitation, which resulted in serious underestimation in China due to its waste properties: high moisture contents. To overcome this problem, a new estimation method was established considering two sources: (1) precipitation infiltrated throughout waste layers, which was simulated with the HELP model, (2) water squeezed out of the waste itself, which was theoretically calculated using actual data of Chinese waste. The two sources depended on climate conditions and waste characteristics, respectively, which both varied in different regions. In this study, 31 Chinese cities were investigated and classified into three geographic regions according to landfill leachate generation performance: northwestern China (China-NW) with semi-arid and temperate climate and waste moisture content of about 46.0%, northern China (China-N) with semi-humid and temperate climate and waste moisture content of about 58.2%, and southern China (China-S) with humid and sub-tropical/tropical climate and waste moisture content of about 58.2%. In China-NW, accumulated leachate amounts were very low and mainly the result of waste degradation, implying on-site spraying/irrigation or recirculation may be an economic approach to treatment. In China-N, water squeezed out of waste by compaction totaled 22–45% of overall leachate amounts in the first 40years, so decreasing the initial moisture content of waste arriving at landfills could reduce leachate generation. In China-S, the leachate generated by infiltrated precipitation after HDPE geomembranes in top cover started failing, contributed more than 60% of the overall amounts over 100years of landfilling. Therefore, the quality and placing of HDPE geomembranes in the top cover should be controlled strictly for the purpose of mitigation leachate generation.
We provide a theory-driven review of empirical research in diversity climate to identify a number of problems with the current state of the science as well as a research agenda to move the field ...forward. The core issues we identify include (a) the fact that diversity climate is typically treated as unidimensional, whereas diversity research would suggest that there are two major perspectives that could be reflected in diversity climate—efforts to ensure equal employment opportunity and the absence of discrimination versus efforts to create synergy from diversity; (b) a tendency to let the level of analysis (individual psychological climate or shared team or organizational climate) be dictated by convenience rather than by careful theoretical consideration, thus sidestepping key issues for research concerning the causes and consequences of the sharedness, or lack thereof, of diversity climate perceptions; and (c) the tendency to include diversity attitudes and other nonclimate elements in climate measures even though they are different from climate both conceptually and in their antecedents and consequences. The research agenda we advance suggests a need both for different operationalizations and for new research questions in diversity climate, diversity, and relational demography research.
Utilization of urban green vegetation (UGV) has been recognized as a promising option to mitigate urban heat island (UHI) effect. While we still lack understanding of the contributions of local ...background climate to the cooling effect of UGV. Here we proposed and employed a cooling effect framework and selected eight typical cities located in Temperate Monsoon Climate (TMC) and Mediterranean Climate (MC) demonstrate that local climate condition largely affects the cooling effect of UGV. Specifically, we found increasing (artificial) rainfall and irrigation contribute to improving the cooling intensity of grassland in both climates, particularly in the hot-dry environment. The cities with high relative humidity would restrict the cooling effect of UGV. Increasing wind speed would significantly enhance the tree-covered while weakening the grass-covered UGVs' cooling effect in MC cities. We also identified that, in order to achieve the most effective cooling with the smallest sized tree-covered UGV, the area of trees in both climate zones' cities should generally be planned around 0.5 ha. The method and results enhance understanding of the cooling effect of UGVs on larger (climate) scales and provide important insights for UGV planning and management.
Climate Change Biology is a new textbook which examines this emerging discipline of human-induced climate change and the resulting shifts in the distributions of species and the timing of biological ...events. The text focuses on understanding the impacts of human-induced climate change, but draws on multiple lines of evidence, including paleoecology, modelling and current observation. Climate Change Biology lays out the scope and depth of understanding of this new discipline in terms that are accessible to students, managers and professional biologists. * The only advanced student text on the biological aspects of climate change* Examines recent and deep past climate change effects to better understand the impacts of recent human-induced changes* Discusses the conservation and other ecological implications of climate change in detail* Presents recipes for coping with accelerating climate change in the future* Includes extensive illustrations with maps diagrams and color photographs.
I denne artikkelen tar vi for oss den nasjonale klimatilpasningspolitikken i Norge, med utgangspunkt i feltets nyere historie, hvordan feltet er organisert, og hvilket innhold som preger det. Vi ...analyserer spørsmålet om hvorvidt og hvordan den norske klimatilpasningspolitikken er knyttet til en risiko- og sikkerhetsorientert tilnærming, og hvilke konsekvenser dette har for tilnærmingen til styring av feltet. Med utgangspunkt i sentrale politiske dokumenter og et sett intervjuer med aktører på nasjonalt nivå, viser vi hvordan klimatilpasningsfeltet dels er preget av å være både horisontalt komplekst og fragmentert, dels hvordan en risikoorientering gradvis har kommet til å prege politikkens innhold og virkemåte, og dels hvordan denne risikoorienteringen gjør grensegangen til beredskap om samfunnssikkerhet uklar. Til tross for at lokale nivåer har drevet klimatilpasning i lang tid, er den nasjonale klimatilpasningspolitikken av nyere dato og et noe umodent politikkfelt – i den forstand at initiativene på overordnet plan har vært få, og at klimatilpasningspolitikken er direkte avhengig av politikken som føres i den enkelte sektor. Det spredte ansvaret gir sprikende fokus, uklar ansvarsdeling og klare koordineringsbehov. Samtidig er det nasjonale nivået på mange måter isolert fra utfordringene, som i praksis faller på kommunenivået. Til tross for at en tiltagende risikoorientering preger styringsnormene, gir ikke dette utslag i retning av en ‘sikkerhetisering’ som leder til ekstraordinære styringsmessige tiltak; tvert imot håndteres klimatilpasning som normalpolitikk innenfor rammene av eksisterende strukturer.
Global food production is identified as a great threat to the environment. In combination with technical advances in agriculture, dietary change is suggested to be necessary to reduce the ...environmental impact of the food system. In this article a systematic review assessing the environmental impact of dietary change is performed. The aims are to i) evaluate the scientific basis of dietary scenario analysis, ii) estimate the potential environmental effects of dietary change, iii) identify methodological aspects of importance for outcome and iv) identify current gaps in knowledge. The review includes 14 peer-reviewed journal articles assessing the GHG emissions and land use demand of in total 49 dietary scenarios. The results suggest that dietary change, in areas with affluent diet, could play an important role in reaching environmental goals, with up to 50% potential to reduce GHG emissions and land use demand associated with the current diet. The choice of functional unit, system boundaries and methods for scenario development and accounting for uncertainties are methodological aspects identified to have major influence on the quality and results of dietary scenario analysis. Further understanding of dietary change as a measure for more sustainable food systems requires improved knowledge of uncertainty in dietary scenario studies, environmental impact from substitutes and complements to meat and the effect of dietary change in different groups of populations and geographical locations. (C) 2014 Elsevier Ltd. All rights reserved.
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