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Identifying the main factors influencing the land surface temperature (LST) of each local climate zone (LCZ) built type is of great significance for controlling LST. This study investigated the main factors influencing the LST of each LCZ built type in two Asian megacities: Tokyo and Shanghai. Each area in both megacities was classified according to the LCZ scheme. The diurnal LST, pervious surface fraction (PSF), surface albedo (SA), average building height ( 〈 B H 〉 ), and gross building coverage ratio (λp) of each LCZ were also calculated. Finally, the influence of the properties of each LCZ built type on LST was investigated. The results demonstrated that the main factors influencing LST of different LCZ built types differed in Tokyo and Shanghai. 〈 B H 〉 was the main factor influencing LST for compact mid-rise and open high-rise types in Tokyo, and the compact mid-rise type in Shanghai; PSF was the main factor influencing LST for other LCZ built types. Moreover, both 〈 B H 〉 and PSF negatively correlated with LST. Based on the above results and characteristics of each LCZ built type, specific LST mitigation strategies for each LCZ built type were proposed for Tokyo and Shanghai. The approach in this study can contribute to perspectives for urban planners and policymakers to develop highly feasible and reasonable LST mitigation strategies. [ABSTRACT FROM AUTHOR]

Sea breezes are important in a coastal urban climate; however, the impact of urban development on the effects of sea breezes, which decrease air temperature and increase humidity, has not been understood quantitatively. To quantitatively evaluate this impact in Sendai, Japan over the past twenty years, this study analyzed the heat balance mechanisms in urban spaces based on the simulation results of the Weather Research and Forecasting (WRF) model coupled with Local Climate Zone (LCZ) maps. Compared to the observation data on air temperature, specific humidity, and wind in August 2002, results of the numerical simulation, using the 2002 LCZ map and the meteorological conditions of August 2002, confirmed that the WRF model could reproduce meteorological factors well. Thereafter, two numerical simulations using the LCZ maps from 2002 and 2022 were conducted based on the same meteorological condition, from 25 July to 1 September 2008, to extract the impact of urban development on the effects of sea breeze. Consequently, when land use changed from urban built-up land to natural land cover, both the effects of sea breeze—decreasing air temperature and increasing humidity—decreased. Additionally, increases in LCZ 3 (compact low rise), mainly from LCZ 6 (open low rise) and LCZ 9 (sparsely built), decreased the effects of sea breeze (decreasing air temperature and increasing humidity) by 5% and 10%, respectively, in areas around Sendai Station. This was because the consumption of the sea breeze's potential to decrease air temperature and increase humidity increased and the wind speed of sea breezes decreased in the windward areas of Sendai Station. These results provide new insights into the impact of urban development on the effects of sea breeze and quantitatively reveal changes in the effects of sea breeze. [ABSTRACT FROM AUTHOR]

High-rise buildings cause accelerated winds around them. However, the interference effects of high-rise buildings on the surrounding low-rise buildings in urban blocks have not been evaluated. This study investigated the wind pressure coefficients on the roofs and walls of low-rise buildings surrounding a high-rise building through wind tunnel experiments. Seventy-two wind directions were considered from 0° to 355° in 5° increments, and the influence of the wind direction on the wind pressure coefficients of surrounding buildings was evaluated. At a 30° wind direction angle, the positive and negative peak wind pressure coefficients occurred in a low-rise building at the leeward side of the high-rise building. The positive peak pressure, approximately 1.4 times that without a nearby high-rise building, occurred at the windward corner on the front wall of a low-rise building. The negative peak value, approximately three times that without a nearby high-rise building, was observed at the windward edge on the roof of a low-rise building. Thus, accelerated winds caused by high-rise buildings may result in unexpected damage to the surrounding low-rise buildings. [ABSTRACT FROM AUTHOR]

The Local Climate Zone (LCZ) scheme is an urban classification system which classifies urban areas into discrete local climates by morphological and land cover characteristics, proposed based on urban heat island researches in 1970s to 2000s. However, while the original scheme defines high‐rise buildings as areas higher than 25 m on average, buildings over 100 m have become more common in Asia since the 2000s. With the heterogeneity of urban areas, directly applying the original LCZ scheme to Asian cities has become difficult. Studies to incorporate the heterogeneity of urban morphology into the scheme have been conducted by researchers, although the increase in the number of taller buildings is not explored. This study proposes, LCZ categories and standards considering the super high‐rise buildings in Asian cities for a detailed categorization of urban morphology. For this, the urban morphological characteristics of Tokyo Metropolis, with a wide range of morphologies that exist in Asian cities, were analyzed. The proposal was made based on this analysis in relation to the thermal characteristics. Then, the characteristics of land surface temperature in each LCZ category were investigated in Shanghai and Xi'an, which indicated the applicability of the proposed categories to mid to large scale Asian cities. [ABSTRACT FROM AUTHOR]

As the longest-serving Prime Minister so far, Abe Shinzo will be remembered for the unprecedented shifts he brought about in Japan's security policies, which will most likely have a lasting impact. From creating new institutions to fundamental changes in decision-making and from constructing a new framework for defense strategy and acquisition of offensive military capabilities to deftly managing the alliance with the US, Abe has left an indelible mark. He also came up with the Indo-Pacific construct and the Quad, which have become the key facets of regional security. Abe's initiatives are radical, but will they lead Japan to charter an equally new radical path? [ABSTRACT FROM AUTHOR]

• Long-term MRT distribution around a building were predicted. • The back propagation neural network and genetic algorithms (GA-BPNN) was optimized. • GA-BPNN were proved as a stable and accurate one for long-term MRT prediction. • MAPE and RMSE of the optimized model were lower than 1% and 1°C. Urban warming has become increasingly serious in recent years. Especially in the case of hot summer days (with maximum daily temperature greater than 30°C), the number of people suffering from heat stroke increases every year. To mitigate urban warming and adapt to it, many researchers have focused on improving outdoor thermal comfort. The mean radiant temperature (MRT) is one of the most important variables affecting human thermal comfort in outdoor urban spaces; however, the process of MRT calculation requires a lot of computing power and time. The main objective of this study is the optimization of the back propagation and genetic algorithms on the basis of a multilayer neural network (MLNN), as an alternative to the time-consuming and computationally intensive process for quick MRT prediction. In this research work, a neural network was trained using the relevant weather-related and building morphology-related parameters that may affect the MRT from 2014-2018 as training parameters, the distributions of MRT around buildings in hot summer days of 2019 were predicted using an optimized neural network model. The results show that the mean absolute percentage error (MAPE) and root-mean-square error (RMSE) of the optimized model were lower than 1% and 1°C. [ABSTRACT FROM AUTHOR]