Climate Of City Research Articles

A case in subtropical climate city: Assessing the bioretention hydraulic performance on storm in response to poor permeability soil

Bioretention has been widely used in China for the purpose of sponge city construction. In subtropical climate areas, the performance of bioretention cell under condition of low infiltration underlying soil and heavy storms is still poorly understood. This study aimed to assess the effects of low infiltration underlying soil and precipitation characteristics on the hydraulic performance of a bioretention cell using the Storm Water Management Model (SWMM). The hydraulic performance of a bioretention cell were investigated under a Typical year rainfall event (P(total) (total precipitation) = 1299.2 mm) and seven heavy storms (i.e., Ptotal range from 53.1 mm to 287.3 mm), at different SF(i) (seepage rates of the underlying soil) (i.e., range from 2.5 mm/h to 15 mm/h). Then, sensitivity of the optimal design to the different design parameters, including the hydraulic conductivity of soil medium layer and the berm height of surface layer, was examined. The results show that the increase in SF(i) was effective in increasing the ARVR(i) (annual runoff volume reduction) and RVR(i) (runoff volume reduction), while little effective in increasing PFR(i) (peak flow reduction). Moreover, the ARVR(i) could meet the designed goal of 70% when the SF(i) was more than 7.5 mm/h. For RVR(i), the key variable of precipitation characteristic changes from Ptotal to P4h(max) (maximum precipitation in 4 h) as SF(i) increases, while P4h(max) remains as the key variable for PFR(i) all the time. The sensitivity studies demonstrate that the hydraulic conductivity is more effective in increasing PFR(i) than the berm height. For the bioretention cell under condition of low infiltration underlying soil and heavy storms, in order to simultaneously achieve expected reduction goal of both peak flow and runoff volume, and make the best comprehensive performance of bioretention cell, it requires not only a maintenance action to increase the hydraulic conductivity of soil medium layer, but also a drain pipe to be added in the storage layer, and meanwhile other LID practices should be combined.

Energy-saving of building envelope using passive PCM technique: A case study of Kuwait City climate conditions

In the Kuwaiti climate region, the residential sector accounts for 64% of electricity consumption. Due to the hot climate for this region, the share of cooling power usage to meet the ventilation requirements in residential buildings is significant. One of the effective methods to reduce power usage is to reduce heat gain. In this numerical study, taking into account the Kuwait City climate region, a PCM layer with a thickness of 20 mm was added to the vertical walls as well as the roof to examine the heat exchange reduction. In the warmeth month (July) by adding PCM of RT-42 to the roof, the heat gain reduced by 15.37%, while this figure for vertical walls was approximately 13.78% which implies that the geographical direction has not considerable effects on PCM usefulness. To investigate the effects of melting temperature on heat gain, three PCMs of RT-31 (phase change temperature of 27–33 °C), RT-35 (29–36 °C and RT-42 (38–43 °C) were examined. Annual calculations showed that RT-31 effectiveness was better than other PCMs so that loading RT-31 into vertical walls + roof resulted in energy saving as well as CO2 saving by 481kWhm2.year and 198.65kgCO2m2.year, respectively.

RETRACTED ARTICLE:The impact of vegetation change and climate in coastal cities on public sports: the impact of urban heat island

The process of urbanization is the most important human activity since the twentieth century. Due to the unique environmental problems brought about by urbanization, urban heat islands not only affect regional economic development and regional climate but also bring comfort to urban residents and energy consumption. The negative impact is obvious, so the study of urban heat island effect is very important to monitor regional and even global climate change and guide urban development plans. First of all, this paper takes the coastal megacities along the Belt and Road as the research object, based on MODIS surface temperature products and Landsat land use classification data, and uses urban heat island intensity as an indicator to analyze the heat islands of 10 megacities from an interannual and seasonal perspective from 2004 to 2020. The effect of the spatio-temporal pattern changes; then, taking a city as an example, based on Landsat land use classification data, RS and GIS technology is used to analyze the land use cover change and urban expansion of a city in the past 30 years; finally, according to Landsat surface temperature data and land using classified data, the impact of land use and cover characteristics on urban heat islands in a city was investigated. Outdoor sports organizations and operators in SD coastal cities found that the outdoor sports organizations and operators in SD coastal cities did not make full use of the geographical environment, economic development, and cultural environment of coastal cities and fully analyzed the comprehensive and systematic problems in the organization and management of outdoor sports, so that outdoor sports organizations and operators in SD coastal cities can give full play to their advantages. Through this research, we will promote a more comprehensive understanding of the healthy and sustainable development of outdoor sports and promote the organization and development of outdoor sports. Management research provides a theoretical basis.

Effects of extreme temperature on respiratory diseases in Lanzhou, a temperate climate city of China.

Under the global climate warming, extreme weather events occur more and more frequently. Epidemiological studies have proved that extreme temperature is strongly correlated with respiratory diseases. We evaluated extreme-temperature effect on respiratory emergency room (ER) visits for 5 years in Lanzhou, a northwest temperate climate city of China from January 1st, 2013, to August 31st, 2017. We built a distributed lag non-linear model (DLNM) to evaluate the lag effect up to 30 days. Results showed the relative risk (RR) of respiratory disease always reached the maximum at lag 0 day and decreased to 1.0 at lag 5 days. Extremely low temperature showed the lag effect of 22 days and the maximum RR was 1.415 (95% CI 1.295-1.546) at lag 0 day. Extremely high temperature showed the lag effect of 7 days and the maximum RR was 1.091 (95% CI 1.069-1.114) at lag 0 day. The elders (age > 65 years) were at the greatest risk to extreme temperatures and the response were very acute. Children (age ≤ 15 years) were at the lowest risk but the lag effect lasted the longest lag days than other subgroups. Males showed longer-term lag effect and higher RR than females. Our study indicated that the extremely low temperature has a significantly greater effect on respiratory diseases than extremely high temperature.

Representing ‘Place’: City Climate Commissions and the Institutionalisation of Experimental Governance in Edinburgh

Against the backdrop of increasingly fragmented and poly-centric urban climate governance, this article examines the establishment of city climate ‘commissions’ as an experimental means of addressing the challenge of climate change at the city-scale. In doing so it addresses the question: What constitutes diversity in voices and perspectives when trying to represent the city as a place for climate action? To answer this question, the article presents an analysis of the Edinburgh Climate Commission’s establishment, drawing on participatory ethnographic research carried out by a researcher embedded within the project team. The account of how this new mode of urban governance was both conceptualised and then put into practice offers a new institutional angle to the literature on urban ‘experimentation.’ Through our reflective analysis we argue that aspirations to ensure pre-defined ‘key’ industries (high carbon emitters) are accounted for in commissioner recruitment, and an over-emphasis on capturing discernible ‘impacts’ in the short term (by involving organisations already pro-active in sustainable development) hindered an opportunity to embrace new perspectives on urban futures and harness the innovative potential of cities to engage with the multifaceted nature of the climate challenge. Furthermore, new insight into the relationship between local authorities and other ‘place-based’ agents of change opens up important questions regarding how to balance the attainment of legitimacy within the political status quo, and the prospect of a new radical politics for urban transformation.

Thermo-economic analysis of a novel integrated structure for liquefied natural gas production using photovoltaic panels

As natural gas is not uniformly distributed in different regions of the world, and gas tanks are concentrated in specific geographical areas, gas transfer is a key gas-related industry that greatly contributes to the expansion of this energy carrier's use. For long distances, the use of pipeline transport is uneconomical in practice, and alternative methods should be adopted. From among alternative methods to pipeline transport, natural gas liquefaction is the best and most economic one. A major challenge to the expansion of liquefied natural gas (LNG) use is the energy-consuming process of its production. The liquid gas production process, like other liquefaction processes, consumes considerable amounts of energy. In this paper, a solar energy and natural gas storage method was developed for transfer to far-away regions for demand response by using the DMR compression refrigeration cycle, Kalina power production cycle, and photovoltaic solar panels for the climate of Chabahar coastal city in Southern Iran. The dissipated heat from the DMR compression refrigeration cycle was used as the heat source for the Kalina cycle. The coefficient of performance, specific energy consumption, and exergy yield of the developed integrated structure were 3.201, 0.2293 kWh kg−1 LNG, and 42.77%, respectively. The exergy analysis of this integrated structure showed that the largest shares of exergy destruction belonged to solar panels (86.29%) and heat exchangers (6.51%), respectively. The economic analysis of the integrated structure revealed that the payback period, the prime cost of product, and additive value equaled 2.061 years, 0.2500 US$ kg−1 LNG, and 0.1156 US$ kg−1 LNG, respectively. The results of sensitivity analysis demonstrated that, for the capital cost of 2100 MMUS$ and less, the payback period is < 4 years.

Multi-level climate change planning: An analysis of the Italian case

As recognized by the Paris Climate Agreement of the United Nations Framework Convention on Climate Change (UNFCCC), local and subnational regions are crucial actors to achieve international mitigation and adaptation commitments. Scientific literature and empirical evidence point at multi-level climate governance as a crucial factor to engage subnational levels in the achievement of national and international objectives. This work focuses on the multi-level climate governance arrangements in Italy to investigate how Italian regions/provinces/cities are contributing to the achievement of national commitments. To this purpose, the paper undertakes a review of the climate policies of different tiers of government adopted to date and of the interrelationships among them. The results of the analysis show that the effective coordination between the different government levels should be strengthened to further incentivize and support initiatives at the local level. Results also show the relevant role played by international regional and city climate networks in boosting local and regional climate planning in Italy.

Network governance in addressing climate change: a case study of the Asian Cities Climate Change Resilience Network (ACCCRN) in Indonesia

The Asian Cities Climate Change Resilience Network (ACCCRN) is an international institution assisting the Indonesian government to address climate change by incorporating many institutions. Nevertheless, we still lack an understanding of how the network is established in the process of handling climate change between ACCCRN and related agencies in Indonesia. This paper examines network governance during the involvement of ACCCRN in Indonesia. The purpose of the paper is to explore the network established by the ACCCRN in helping the Indonesian government to reduce the impact of climate change. We used a desk study by employing secondary sources to identify the actors, the relationship among the actors, and the outcome of the networks. We suggest that ACCCRN has played a crucial role in reducing the impact of climate change by cooperating with various organisations in Indonesia. In doing so, there are a number of public and non-profit agencies encompassed in the process of collaboration. This study recommends the government to maintain and increase numerous partnerships between international and local institutions in arranging climate change.

A scoring scheme prediction model for dengue outbreaks using weather factors in Ho Chi Minh city, Vietnam

The dengue infection cases are increasing in Ho Chi Minh city (HCMC), Vietnam. Previous studies have demonstrated the correlation between dengue cases and weather factors, which then are used to built prediction models for dengue outbreaks. However, the association between dengue and weather varies greatly between regions and locations. In HCMC, a tropical climate city in Vietnam, there is no such a weather-based prediction model for dengue outbreaks. This study aims to determine the correlation between weather factors and a weekly number of dengue cases and to develop a scoring scheme prediction model for dengue outbreaks using weather factors in HCMC, Vietnam. An ecological study was conducted on the evaluation of weekly time-series data from 1999 to 2017. A Poisson regression model coupled with Distributed Lag Non-Linear Model (DLNM) was constructed to evaluate the effects of weather factors (i.e., temperature, relative humidity, cumulative rainfall, wind speed) and the weekly dengue cases in HCMC with lag 1-12 weeks. The predictive model was based on the following weather factors: wind speed at lag 5-8 and 9-12 weeks; temperature amplitude and humidity at lag 5-8 weeks; rainfall at lag 1-4, 5-8, and 9-12 weeks. The predictive model using climate predictors explained about 80% of the variance in dengue cases with a small value of the mean absolute percentage error (MAPE= 0.17). The scoring scheme was then developed from the predictive model; it had a good prediction power – with the accuracy rate = 81%, sensitivity = 1, and specificity = 0.80. In summary, our study indicated that weather factors significantly influence and are predictors for the variation of dengue cases in Ho Chi Minh city, Vietnam. We recommend applying this model to improve the prevention of dengue outbreak.

The Impact of Natural Elements on Environmental Comfort in the Iranian-Islamic Historical City of Isfahan

Cities directly influence micro-climates. As the urbanization expands, and the green spaces diminish, the heat islands begin to emerge. An old technique used during the past centuries — in both hot and dry climates of the central cities of Iran — was the moderation of micro-climates via water and plants. With a diachronic approach to the study of the historical Chahar Bagh Street in Isfahan, this paper investigates the impact of the structural changes on its micro-climate in three different scenarios, i.e., the street with its features during the Safavid Era (from 1501 to 1736); the street in its current status; and finally a probable critical condition resulting from complete elimination of natural elements from the environment. The mixed strategy used in this study relies on logical reasoning and software-assisted evaluation for comparing the three scenarios. The predicted mean vote (PMV) model was used for measuring thermal comfort. The results indicate that the evaluated comfort-providing area in the Safavid scenario is 7–17 times more favorable than the others. Moreover, the temperature in the contemporary era was found to be 1.5 degrees Celsius cooler than that of the critical status scenario.

Climate action for health and wellbeing in cities: a protocol for the systematic development of a database of peer-reviewed studies using machine learning methods

Cities produce more than 70% of global greenhouse gas emissions. Action by cities is therefore crucial for climate change mitigation as well as for safeguarding the health and wellbeing of their populations under climate change. Many city governments have made ambitious commitments to climate change mitigation and adaptation and implemented a range of actions to address them. However, a systematic record and synthesis of the findings of evaluations of the effect of such actions on human health and wellbeing is currently lacking. This, in turn, impedes the development of robust knowledge on what constitutes high-impact climate actions of benefit to human health and wellbeing, which can inform future action plans, their implementation and scale-up. The development of a systematic record of studies reporting climate and health actions in cities is made challenging by the broad landscape of relevant literature scattered across many disciplines and sectors, which is challenging to effectively consolidate using traditional literature review methods. This protocol reports an innovative approach for the systematic development of a database of studies of climate change mitigation and adaptation actions implemented in cities, and their benefits (or disbenefits) for human health and wellbeing, derived from peer-reviewed academic literature. Our approach draws on extensive tailored search strategies and machine learning methods for article classification and tagging to generate a database for subsequent systematic reviews addressing questions of importance to urban decision-makers on climate actions in cities for human health and wellbeing.

Climate action for health and wellbeing in cities: a protocol for the systematic development of a database of peer-reviewed studies using machine learning methods.

Cities produce more than 70% of global greenhouse gas emissions. Action by cities is therefore crucial for climate change mitigation as well as for safeguarding the health and wellbeing of their populations under climate change. Many city governments have made ambitious commitments to climate change mitigation and adaptation and implemented a range of actions to address them. However, a systematic record and synthesis of the findings of evaluations of the effect of such actions on human health and wellbeing is currently lacking. This, in turn, impedes the development of robust knowledge on what constitutes high-impact climate actions of benefit to human health and wellbeing, which can inform future action plans, their implementation and scale-up. The development of a systematic record of studies reporting climate and health actions in cities is made challenging by the broad landscape of relevant literature scattered across many disciplines and sectors, which is challenging to effectively consolidate using traditional literature review methods. This protocol reports an innovative approach for the systematic development of a database of studies of climate change mitigation and adaptation actions implemented in cities, and their benefits (or disbenefits) for human health and wellbeing, derived from peer-reviewed academic literature. Our approach draws on extensive tailored search strategies and machine learning methods for article classification and tagging to generate a database for subsequent systematic reviews addressing questions of importance to urban decision-makers on climate actions in cities for human health and wellbeing.

Global 1-km present and future hourly anthropogenic heat flux

Numerical weather prediction models are progressively used to downscale future climate in cities at increasing spatial resolutions. Boundary conditions representing rapidly growing urban areas are imperative to more plausible future predictions. In this work, 1-km global anthropogenic heat emission (AHE) datasets of the present and future are constructed. To improve present AHE maps, 30 arc-second VIIRS satellite imagery outputs such as nighttime lights and night-fires were incorporated along with the LandScanTM population dataset. A futuristic scenario of AHE was also developed while considering pathways of radiative forcing (i.e. representative concentration pathways), pathways of social conditions (i.e. shared socio-economic pathways), a 1-km future urbanization probability map, and a model to estimate changes in population distribution. The new dataset highlights two distinct features; (1) a more spatially-heterogeneous representation of AHE is captured compared with other recent datasets, and (2) consideration of future urban sprawls and climate change in futuristic AHE maps. Significant increases in projected AHE for multiple cities under a worst-case scenario strengthen the need for further assessment of futuristic AHE.

Making Indian cities climate and water resilient

The article highlights flood risk and governance challenges in India. With reference to the recent Chennai floods, it elaborates on past mistakes and the way forward to improve the resilience of Indian cities to manage climate disasters.

Exploring city climate leadership in theory and practice: responding to the polycentric challenge

ABSTRACT This article has a twofold aim inspired by observed gaps in urban climate governance theory and practice. First, it explores city leadership strategies of securing a closer correspondence between climate policy goals and observed realities on the ground. Second, it presents an in-depth and nuanced theoretical understanding of urban climate leadership inspired by four bodies of public administration leadership theory, reflecting leadership as an understudied field in the urban climate governance literature. Being largely exploratory and conceptual in nature, the article aims more specifically to identify the contribution of different public leadership theories and strategies to our understanding of city climate leadership, the explanatory reach and limitations of the theories and the potential interdependency between the leadership strategies. The practice of climate leadership in the city of Oslo is used as an illustrative case. The results show that each body of theory shed light on relevant aspects of climate leadership practices in diverse institutional contexts. By applying a careful mix of these leadership strategies and instruments, city leadership adds the stringence, predictability and motivation needed for multiple public and private actors to engage collectively and bridge policy gaps. However, social, institutional and physical constraints related to the complex, polycentric character of urban climate governance represent phenomena that fall outside the scope of the leadership theories. This point to limitations in the theories’ explanatory reach that give direction to future research.

Growing media for food and quality of life in the period 2020-2050

Growing media in soilless cultivation allow growers to apply water and nutrients more accurate (+15% growth) and to avoid soil diseases (+5/50% growth). Growing media, in combination with recirculation of drainage solution, reduce water use by about 50% and nutrient use by about 60%. For that and other reasons it is expected global growing media use will increase. A more precise estimation of the increase in demand is made, based on the expected growth of the world population, the expected increase in living standards for most people and the influence of several trends. Trends for vegetables include the need to address obesities, chronic micronutrient deficiencies and product safety. Trends for ornamentals include appreciation of natural aesthetics and ameliorating indoor climate and city climate. General trends include dealing with water scarcity, urbanisation, and more. The consequences of the possible higher demand are discussed in view of the availability of common growing media constituents like peat, coir, wood fiber, bark, compost, perlite, stone wool and tuffs as well as for less common but potentially available growing media (constituents) like Sphagnum, water and biochar. The influence of irrigation, drainage and support systems on growing media preference are discussed, as affected by trends, including recirculation of drainage solution, the use of organic fertilisers and developments in remote growing. In conclusion, the global growing media market is highly dynamic with the potential to increase four-fold between 2017 and 2050 with the highest per continent use shifting to Asia. The population increase is expected to contribute about 40%, income increase about 80% and trends about 40% for vegetables and 270% for ornamentals, totalling a market increase of 260% for vegetables and 490% for ornamentals. Growing media can contribute to a more sustainable production of vegetables and ornamentals as well as to public health and quality of life.

Study on the architectural layout of urban settlements in cold regions based on climate and environmental impact factors

The outdoor wind environment has a significant impact on the climate of cold-weather cities, and it has been shown that building layout has a significant correlation with the climate environment. This paper takes Changchun, a cold-land city in the northeast of China, as an example to study the correlation between the existing building layout and the wind environment in a cold-land city based on its special climate environment, uses computational fluid dynamics (CFD) simulation technology to analyze the influence of different building layouts on the external wind environment in a cold-land city, explores the building layout mode suitable for a cold-land city based on the obvious characteristics of the climate monsoonal changes, and puts forward certain optimization methods and reference suggestions for city construction.

Effects of supply Diffuser Shape on Air Age and Human Comfort in an Office with Displacement Ventilation and Chilled Ceiling System in Hot and Dry climate

In recent years, the need to provide a clean environment in enclosed places has drawn increasing levels of attention due to the spread of epidemics and viruses across the world. Chilled ceilings with displacement ventilation represent promising technology. The combined ventilation system has not yet been used in Iraqi buildings, then it’s a good starting point for study the performance of this system in Iraq-Hilla city climate (hot and dry climate). An office room with a combined ventilation system was simulated using AIRPAK software. Indoor air age, air temperature distribution, CO2 concentration and thermal efficiency were estimated numerically. During the simulation process, the effects of two different supply diffuser shapes (one way rectangular diffuser and semicircle diffuser) were compared to investigated the effect of supply diffuser shape on air age and thermal environment in hot and dry climate (passed on peak summer temperatures in Hilla city). Three tests were performed for each case based on changing the load treated by the chilled ceiling as (25%, 50% and 80%) respect to total cooling load and represented (26, 53, 85W/m2) respectively based on floor area. The temperature of chilled ceiling surface varied as (21.5, 19 and 16°C) and the air supply temperature similarly varied (19, 22, and 24.5 °C) respectively at constant air flowrate of (0.045m3/s). The results of the tests found that the effect of diffuser shape on the local age of air decreased with height, the maximum difference between two cases at the 0.1m level was about 49s while at 2.25m level it was only about 11s. The air exchange efficiency for the CC/DV system using a semicircle diffuser in the predetermined office space was higher by an average of 8.5% as compared with a similar system using a rectangular diffuser; this differential reduced about 3% at each increase in portion of cooling load treated by the chilled ceiling, however.

Thermal Comfort Assessment and Heat-Related Illnesses among Sellers in Periodic Local Markets: A Case Study in Hot and Dry Climate of Iran

Background:This study aims to evaluate the thermal conditions of periodic local markets and determine the thermal comfort and sensation of sellers, as well as the prevalence of heat-related diseases in the hot and dry climate of Iran.&#x0D; Methods:In this study, thermal comfort and sensation of 330 sellers from periodic markets in Qom city, a dry and hot climate in Iran, were evaluated. Measurements were performed for 15 days, from July 16 to August 1. To assess environmental thermal condition, wet bulb globe temperature (WBGT) index and discomfort index (DI) were determined, and participants' tympanic temperature was determined to consistency assessment with thermal indices. Finally, the effects of environmental, personal, and working conditions on the prevalence of heat-related diseases among sellers were determined.&#x0D; Results:The environmental indices, including DI and WBGT index, had the most association with heat-related illnesses and tympanic temperature (P&lt;0.05). The sellers perceived the environmental conditions as warm to hot after 1:00 pm. Besides, they expressed an uncomfortable or very uncomfortable situation after 12:00 pm. The findings showed that environmental parameters play a more important role in the prevalence of heat-related diseases and heat strain than individual and occupational factors.&#x0D; Conclusion:The sellers may be at risk of heat stress in outdoor markets in nearly half of the workday in the summer months. Therefore, it is very important that these people receive the necessary training in the prevention of heat illness in order to take appropriate protective measures in accordance with local conditions.

Multi-Risk Climate Mapping for the Adaptation of the Venice Metropolitan Area

Climate change risk reduction requires cities to undertake urgent decisions. One of the principal obstacles that hinders effective decision making is insufficient spatial knowledge frameworks. Cities climate adaptation planning must become strategic to rethink and transform urban fabrics holistically. Contemporary urban planning should merge future threats with older and unsolved criticalities, like social inequities, urban conflicts and “drosscapes”. Retrofitting planning processes and redefining urban objectives requires the development of innovative spatial information frameworks. This paper proposes a combination of approaches to overcome knowledge production limits and to support climate adaptation planning. The research was undertaken in collaboration with the Metropolitan City of Venice and the Municipality of Venice, and required the production of a multi-risk climate atlas to support their future spatial planning efforts. The developed tool is a Spatial Decision Support System (SDSS), which aids adaptation actions and the coordination of strategies. The model recognises and assesses two climate impacts: Urban Heat Island and Flooding, representing the Metropolitan City of Venice (CMVE) as a case study in complexity. The model is composed from multiple assessment methodologies and maps both vulnerability and risk. The atlas links the morphological and functional conditions of urban fabrics and land use that triggers climate impacts. The atlas takes the exposure assessment of urban assets into account, using this parameter to describe local economies and social services, and map the uneven distribution of impacts. The resulting tool is therefore a replicable and scalable mapping assessment able to mediate between metropolitan and local level planning systems.