Urban Climates and Climate Change Masson, Valéry; Lemonsu, Aude; Hidalgo, Julia ...
Annual review of environment and resources,
10/2020, Letnik:
45, Številka:
1
Journal Article
Recenzirano
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Cities are particularly vulnerable to extreme weather episodes, which are expected to increase with climate change. Cities also influence their own local climate, for example, through the relative ...warming known as the urban heat island (UHI) effect. This review discusses urban climate features (even in complex terrain) and processes. We then present state-of-the-art methodologies on the generalization of a common urban neighborhood classification for UHI studies, as well as recent developments in observation systems and crowdsourcing approaches. We discuss new modeling paradigms pertinent to climate impact studies, with a focus on building energetics and urban vegetation. In combination with regional climate modeling, new methods benefit the variety of climate scenarios and models to provide pertinent information at urban scale. Finally, this article presents how recent research in urban climatology contributes to the global agenda on cities and climate change.
This paper proposes a method based on a local weather type classification approach to facilitate analysis and communication of climate information in local climate studies. Presented herein is an ...application to urban climatology in Toulouse, France, but the method can be used in other applied fields of climatology as well. To describe the climatic context of this urbanized area, the local weather types that explain the plurality of weather situations Toulouse faces are presented in depth. In order to show the potential for use of this approach, this information is applied to the study of changes in local weather types in terms of frequency and intensity within a series of future climate projections, a classic urban canopy and a series of atmospheric boundary layer analyses, and as a support for communication aimed to initiate urban climate awareness in urban planning practices. The proposed classification method has been coded in an R script and is provided as a supporting information file. The paper concludes that a systematic pre-study using this kind of climatic analysis is a good practice for performing climatic contextualization in local scale applied studies, both for scientific analysis and communication.
•Hydrotalcites containing DBS are effectively delaminated in 1-butanol.•Exfoliated solid was ion-exchanged to obtain discrete LDH nanolayers.•Calcining delaminated LDH at 450°C produced a solid ...highly basic.•The calcined solids exhibited excellent conversion in MPV reaction.
The Meerwein–Ponndorf–Verley (MPV) reaction involves the hydrogen-transfer reduction of a carbonyl compound by an alcohol used as hydrogen donor. The process is catalysed by both homogeneous and heterogeneous catalysts. The latter can be of the acid or basic type. In this work, we used delamination and ion-exchange in combination to obtain delaminated solids from layered double hydroxides (LDHs). Three Mg/Al LDHs (Mg/Al ratio=2) containing carbonate, hydroxyl or dodecylbenzenesulphonate (DBS) as interlayer anion were prepared using a coprecipitation method or by rehydration of the solid obtained by calcinations of carbonate containing LDH. The X-ray diffraction patterns for LDHs exhibited the typical lines for LDHs intercalated with carbonate, hydroxyl or DBS ions. The DBS-containing LDH was delaminated by sonicating at 60°C a suspension of this solid in 1-butanol. The DBS ions in the delaminated LDH could be exchanged by nitrate or hydroxyl ions by stirring a suspension of this delaminated LDH in 1-butanol containing an appropriate amount of Ca(NO3)3 of Ca(OH)2, respectively. The resulting delaminated solids consisted of brucite-like nanolayers excess charge in which was countered by dodecylbenzenesulphonate, nitrate or hydroxyl ions. Some of these solids exhibited moderate catalytic activity in the MPV reaction of benzaldehyde with 2-propanol. The reaction was conducted at 82°C (0.06mol of 2-propanol was treated with 0.003mol of benzaldehyde in the presence of 1g of catalyst). Calcining at 450°C the delaminated LDHs, however, provided solids with a high surface activity that made them highly effective catalysts for the reaction. The catalyst obtained by calcining delaminated LDH containing hydroxyl ions provided the best catalyst (100% conversion after 2h of reaction) and has been used in the MPV reaction of other aldehydes with excellent results.
The urban-breeze circulation is a mesoscale response of the atmospheric flow that is related to horizontal variations in temperature associated, for dry conditions, with gradients in sensible heat ...flux densities. This local circulation is difficult to observe with a simple observational deployment, and the 3D numerical simulations needed to model it are very demanding in computer time. A theoretical approach scaling the daytime urban heat island and urban-breeze characteristics has been developed and provides a simple set of equations that depend on measurable parameters. Three-dimensional high-resolution numerical simulations, performed with the Nonhydrostatic Mesoscale (Meso-NH) atmospheric model, were used to generate a set of urban-breeze circulations forced by an idealized urban environment. The pertinent forcing parameters chosen were the size of the city, the height of the thermal inversion topping the mixed turbulent air layer, and the difference (urban – rural) of surface heat flux. Scaling laws are presented that describe the shape of the urban heat island and the horizontal and vertical wind intensity and profiles.
We suggest applying the chorematic methodology to the processes and issues addressed by the urban climatic mapping framework, i.e., the interdisciplinary discussion and analysis of thematic data, the ...production of analytic maps, and the creation of recommendation maps to advise urban planners. After introducing the method, its theoretical basis, and its process, we discuss its fitness and present the possibility of its application in this thematic context. We then suggest a first series of applications, for diurnal heat stress and nocturnal urban heat island analysis, as an example and basis for further discussions, based on recent work in the Toulouse agglomeration. We also offer graphical models to express recommendations concerning urban climate issues in Toulouse. The process used the choremes table expanded with dynamic models, according to the multi-step method proposed by H. Théry (1988). The produced models are now entering a test phase to discuss the method with urban planners.
This study provides a synthetic overview of thirty years of research devoted to urban climate change in Africa. Which cities in Africa are being researched on the impacts of climate change affecting ...them? What are the main social and urban issues and how are they linked? Is the development of climate services envisaged for these cities? Related to which local issues? Some answers are drawn by text mining the metadata of more than a thousand articles published in the 1991–2021 period and recorded in the Web of Science. The evidences produced are based on the design and exploitation of a taxonomy of keywords forming a set of issues and on their articulation in a network based on their co-occurrences in the articles' metadata. Forty-eight African countries and 134 cities are cited, Cairo, Dar es Salaam, Cape Town, Accra, Lagos, Durban, Nairobi, Addis Ababa, Kampala and Johannesburg being the cities deferring the largest number of studies. The salient urban climate change issues-health, water, energy, social issues and governance, followed by agriculture and food, mitigation, heat, urban territories, risks and hazards-are generally addressed in their interdependences. Urbanization and the implementation of associated policies, as well as the management of water resources, floods health and energy, and land use and land cover changes to a less extent, are proving to be the most pressing challenges. In view of the intricacy of these issues, climate services appear underdeveloped in African cities and barely confined to the acquisition and modeling of environmental data for decision-making in adaptation planning.
Advances in Urban Climate Modeling Hidalgo, Julia; Masson, Valéry; Baklanov, Alexander ...
Annals of the New York Academy of Sciences,
December 2008, Letnik:
1146, Številka:
1
Journal Article
Recenzirano
Cities interact with the atmosphere over a wide range of scales from the large‐scale processes, which have a direct impact on global climate change, to smaller scales, ranging from the conurbation ...itself to individual buildings. The review presented in this paper analyzes some of the ways in which cities influence atmospheric thermodynamics and airborne pollutant transport. We present the main physical processes that characterize the urban local meteorology (the urban microclimate) and air pollution. We focus on small‐scale impacts, including the urban heat island and its causes. The impact on the lower atmosphere over conurbations, air pollution in cities, and the effect on meteorological processes are discussed. An overview of the recent principal advances in urban climatology and air quality modeling in atmospheric numerical models is also presented.
AURA study reported 61% objective response rate and progression-free survival of 9.6 months with osimertinib in patients with EGFR/T790M+ non-small cell lung cancer. Due to lack of real-world data, ...we proposed this study to describe the experience with osimertinib in Spain.
Post-authorization, non-interventional Special Use Medication Program, multicenter, retrospective study in advanced EGFR/T790M+ non-small cell lung cancer. One hundred-fifty five patients were enrolled (August 2016-December 2018) from 30 sites.
progression-free survival. Secondary objectives: toxicity profile, objective response rate, and use of health service resources.
70% women, median age 66. 63.9% were non-smokers and 99% had adenocarcinoma. Most patients had received at least one prior treatment (97%), 91.7% had received previous EGFR-tyrosine kinase inhibitors and 2.8% osimertinib as first-line treatment. At data cutoff, median follow-up was 11.8 months. One hundred-fifty five patients were evaluable for response, 1.3% complete response, 40.6% partial response, 31% stable disease and 11.6% disease progression. Objective response rate was 42%. Median progression-free survival was 9.4 months. Of the 155 patients who received treatment, 76 (49%) did not reported any adverse event, 51% presented some adverse event, most of which were grade 1 or 2. The resource cost study indicates early use is warranted.
This study to assess the real-world clinical impact of osimertinib showed high drug activity in pretreated advanced EGFR/T790M+ non-small cell lung cancer, with manageable adverse events.
Clinical trial registration number: NCT03790397 .
This article presents a dataset of spatial nocturnal Urban Heat Island (UHI) intensities for 45 French urban agglomerations, at a horizontal resolution of 250 m. The urban influence on air ...temperature at 2 m above ground level was obtained by coupling the mesoscale atmospheric model Meso-NH with the land surface model SURFEX-TEB. For each agglomeration, two specific local weather situations that favour the development of a strong UHI in summer are simulated and described in a specfic sheet. Simulation outputs have been postprocessed to 1) identify the time of day when the UHI is the most developed, 2) to merge information from both meteorological situations in order to obtain one synthetic UHI map and 3) a geographical analysis that allows to classify each city among five spatial UHI classes (Concentrated Very High Intensity; Concentrated High Intensity; Limited Intensity; Dispersed High Intensity; and Dispersed Cool Zones). This dataset can therefore be used for several purposes, from the analysis at the scale of a city to the comparison of the urban agglomerations among them.
The WUDAPT (World Urban Database and Access Portal Tools project goal is to capture consistent information on urban form and function for cities worldwide that can support urban weather, climate, ...hydrology and air quality modeling. These data are provided as urban canopy parameters (UCPs) as used by weather, climate and air quality models to simulate the effects of urban surfaces on the overlying atmosphere. Information is stored with different levels of detail (LOD). With higher LOD greater spatial precision is provided. At the lowest LOD, Local Climate Zones (LCZ) with nominal UCP ranges is provided (order 100 m or more). To describe the spatial heterogeneity present in cities with great specificity at different urban scales we introduce the Digital Synthetic City (DSC) tool to generate UCPs at any desired scale meeting the fit-for-purpose goal of WUDAPT. 3D building and road elements of entire city landscapes are simulated based on readily available data. Comparisons with real-world urban data are very encouraging. It is customized (C-DSC) to incorporate each city's unique building morphologies based on unique types, variations and spatial distribution of building typologies, architecture features, construction materials and distribution of green and pervious surfaces. The C-DSC uses crowdsourcing methods and sampling within city Testbeds from around the world. UCP data can be computed from synthetic images at selected grid sizes and stored such that the coded string provides UCP values for individual grid cells.
•WUDAPT pathway to generating gridded urban canopy data at urban and building scales globally is described.•Digital Synthetic City tool, a core methods innovation for WUDAPT Level 1 and 2, is introduced.•WUDAPT's DSG tool digitizes and generates urban to block scale urban canopy parameters from Google type images.•Testbeds provide Beta testing of WUDAPT's Level 1 and 2 methodology and demonstrate model applications from the generated data.
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