Human thermal comfort and urban climate of Zambia’s economic and political hub: a RayMan model study

15 year re-analysis of the urban climate of Amsterdam using WRF &#160;Sytse Koopmans1 ([email protected]), Gert-Jan Steeneveld1, Ronald van Haren2, Albert A.M. Holtslag1.&#160;1 Wageningen University and Research, the Netherlands:2 Netherlands eScience Center, the Netherlands:&#160;&#160;Ongoing world-wide climate change and urbanization illustrate the need to understand urban hydrometeorology and its implications for human thermal comfort and water management. Numerical weather prediction models can assist to understand these issues, as they progress increasingly towards finer scales. With high model resolutions (grid spacing of 100m), effective representation of cities becomes crucial. The complex structures of cities, configuration of buildings, streets and scattered vegetation, require a different modelling approach than the homogeneous rural surroundings. The current urban canopy-layer schemes account for these city specific characteristics, but differ substantially amongst each other due to uncertainty in land use parameters and incomplete physical understanding. Therefore, the hindcasting of the urban environment needs improvement.In this study, we improve the WRF (Weather Research and Forecasting) mesoscale model performance by incorporating observations of a variety of sources using data assimilation (WRF-3DVAR) and nudging techniques on a resolution up to 167 meter. Data assimilation aims to accurately describe the most probable atmospheric state by steering the model fields in the direction of the observations. Specific to urban boundary layers, a novel approach has been developed to nudge modelled urban canyon temperatures with quality controlled urban weather observations. Adjusting the urban fabric accordingly is crucial, because of the large heat storage within urban canopies. The road and wall layers of the urban canopy are adjusted depending on the bulk heat transfer coefficient and urban geometry. Other data assimilation sources consists of WMO synoptic weather observations and volume radar data.The results of the 15-year climatological urban re-analysis are here presented and it is subdivided in three key questions. First, we attempt to answer how large the trends are in human thermal comfort over the 15 year period. Second, we investigate if there are seasonality&#8217;s detected in maximum urban heat island intensities. Earlier found hysteresis-like curves were reproduced to a large extent for for pedestrian level air temperatures. Lastly, we analyse trends in extreme precipitation using simulated precipitation data on one second interval.

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Impact of urbanization level on the interactions of urban area, the urban climate, and human thermal comfort

Applied Geography ◽

10.1016/j.apgeog.2016.12.007 ◽

2017 ◽

Vol 79 ◽

pp. 50-72 ◽

Cited By ~ 29

Author(s):

Kenobi Isima Morris ◽

Andy Chan ◽

Kwami Justina Kwami Morris ◽

Maggie C.G. Ooi ◽

Muhammad Y. Oozeer ◽

...

Keyword(s):

Thermal Comfort ◽

Urban Area ◽

Urban Climate ◽

Urbanization Level ◽

Human Thermal Comfort ◽

Impact Of Urbanization

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ANÁLISE DO CONFORTO TÉRMICO HUMANO NO MUNICÍPIO DE ARAPIRACA – ALAGOAS, UTILIZANDO SOFTWARE MATLAB (ANALYSIS OF THE HUMAN THERMAL COMFORT THE CITY OF ARAPIRACA - ALAGOAS USING SOFTWARE MATLAB)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v7.5.p939-948 ◽

2015 ◽

Vol 7 (5) ◽

pp. 939

Author(s):

Juliete Baraúna dos Santos

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Effective Temperature ◽

Rainy Season ◽

Prolonged Exposure ◽

Urban Climate ◽

Heat Stroke ◽

Human Thermal Comfort ◽

Discomfort Index ◽

The City

Foram obtidas medidas das variáveis meteorológicas temperatura do ar, umidade relativa do ar e velocidade do vento através da estação automática instalada em Arapiraca com a finalidade de monitorar as condições de tempo no município em diferentes períodos (época chuvosa e seca). Sendo utilizado o índice de desconforto (ID), o índice de desconforto de Kawamura (IDK), índice da temperatura efetiva (TE) e o índice de temperatura efetiva em função do vento (TEV). Os valores mais elevados dos índices que foram registrados para o período chuvoso, foram do índice id com aproximadamente 2,5 °C acima dos valores observados da temperatura do ar (em média 26,5 °C), caracterizando crescente desconforto para os indivíduos locais. Para o período seco não houve registros de grandes variações entre os respectivos índices. E assim como no período chuvoso, os valores mais elevados no período seco foram do índice id, indicando nesse período também forte desconforto. Os valores obtidos estiveram condizentes com a literatura, sendo a sensação térmica mais preponderante durante o inverno. E, de acordo com as variações, em todo período de estudo (05 de maio de 2008 a 05 de maio de 2011) a população foi submetida aos alertas de atenção e muito cuidado, situação esta que pôde provocar fadiga ou cãibras, esgotamento e insolação nos casos de exposição prolongada e atividade física. A B S T R A C T Measurements of meteorological variables air temperature, relative humidity and wind speed by automatic station installed in Arapiraca in order to monitor the weather conditions in the city in different periods (dry and rainy season) were obtained. Being used the discomfort index (ID), the discomfort index of Kawamura (IDK), index of effective temperature (TE) and the index of effective temperature as a function of wind (TEv). Higher index values that were recorded for the rainy season, the index id were approximately 2.5 ° C above the observed values of air temperature (average 26.5 ° C), indicating increasing discomfort for local individuals . For the dry period there were no reports of large variations between the respective indices. And just as the rainy season, the highest values in the dry season were the index id, indicating that period also strong discomfort. The values obtained were consistent with the literature, the most predominant wind chill during the winter. And, according to the variations in the study period (May 5, 2008 to 05 maio 2011) the population was subjected to warnings of attention and care, a situation that could cause fatigue or cramps, exhaustion and heat stroke in cases of prolonged exposure and physical activity. Key-Words: Urban climate. Thermal comfort Human. Bioclimatic

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Long-term impact of rapid urbanization on urban climate and human thermal comfort in hot-arid environment

Building and Environment ◽

10.1016/j.buildenv.2018.06.007 ◽

2018 ◽

Vol 142 ◽

pp. 83-100 ◽

Cited By ~ 11

Author(s):

Shereif H. Mahmoud ◽

Thian Yew Gan

Keyword(s):

Thermal Comfort ◽

Urban Climate ◽

Arid Environment ◽

Rapid Urbanization ◽

Human Thermal Comfort ◽

Long Term Impact

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Calculating human thermal comfort and thermal stress in the PALM model system 6.0

Geoscientific Model Development ◽

10.5194/gmd-13-3055-2020 ◽

2020 ◽

Vol 13 (7) ◽

pp. 3055-3065 ◽

Cited By ~ 2

Author(s):

Dominik Fröhlich ◽

Andreas Matzarakis

Keyword(s):

Thermal Comfort ◽

City Planning ◽

Urban Climate ◽

Climate Index ◽

Mean Radiant Temperature ◽

Thermal Indices ◽

Large Eddy Simulation Model ◽

Human Thermal Comfort ◽

Model Based ◽

Radiant Temperature

Abstract. In the frame of the project “MOSAIK – Model-based city planning and application in climate change”, a German-wide research project within the call “Urban Climate Under Change” ([UC]2) funded by the German Federal Ministry of Education and Research (BMBF), a biometeorology module was implemented into the Parallelized Large-Eddy Simulation Model (PALM) system. The new biometeorology module is comprised of methods for the calculation of UV-exposure quantities, a human–biometeorologically weighted mean radiant temperature (Tmrt), as well as for the estimation of human thermal comfort or stress. The latter is achieved through the implementation of the three widely used thermal indices: perceived temperature (PT), Universal Thermal Climate Index (UTCI), as well as physiologically equivalent temperature (PET). Comparison calculations were performed for the PT, UTCI and PET indices based on the SkyHelios model and showing PALM calculates higher values in general. This is mostly due to a higher radiational gain leading to higher values of mean radiant temperature. For a more direct comparison, the PT, PET and UTCI indices were calculated by the biometeorology module, as well as the programs provided by the attachment to Verein Deutscher Ingenieure (VDI) guideline 3787, as well as by the RayMan model based on the very same input dataset. Results show deviations below the relevant precision of 0.1 K for PET and UTCI and some deviations of up to 2.683 K for PT caused by repeated unfavorable rounding in very rare cases (0.027 %).

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Estimating Terrestrial Radiation for Human Thermal Comfort in Outdoor Urban Space

Atmosphere ◽

10.3390/atmos12121701 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1701

Author(s):

Kanghyun Lee ◽

Robert D. Brown

Keyword(s):

Thermal Comfort ◽

Urban Space ◽

Urban Climate ◽

Field Studies ◽

Subtropical Climate ◽

Climate Conditions ◽

Thermal Environments ◽

Human Thermal Comfort ◽

Cfa Zone ◽

Surrounding Areas

Cities inadvertently create warmer and drier urban climate conditions than their surrounding areas through urbanization that replaces natural surfaces with impervious materials. These changes cause heat-related health problems and many studies suggest microclimatic urban design (MUD) as an approach to address these problems. In MUD-related research, although terrestrial radiation plays an important role in human thermal comfort and previous studies use thermal comfort models to identify human heat stress, few studies have addressed the effect of terrestrial radiation. This study develops the ground ratio factor (GRF) model to estimate the different terrestrial radiation according to different ground conditions. Three types of ground materials (asphalt, concrete, and grass) were considered in the model, and field studies were conducted in humid subtropical climate (Cfa) zone during the hot season (13 July to 19 September 2020). The model was validated by comparing the predicated terrestrial radiation (PTR) from the model with the actual terrestrial radiation (ATR). The results showed that there is a statistically significant strong correlation between PTR and ATR. The model can contribute to MUD strategies by updating existing human energy budget models, which can lead to the measurement of more accurate human thermal comfort for mitigating thermal environments.

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Evaluation of human thermal comfort ranges in urban climate of winter cities on the example of Erzurum city

Environmental Science and Pollution Research ◽

10.1007/s11356-016-7902-8 ◽

2016 ◽

Vol 24 (2) ◽

pp. 1811-1820 ◽

Cited By ~ 5

Author(s):

Süleyman Toy ◽

Noémi Kántor

Keyword(s):

Thermal Comfort ◽

Urban Climate ◽

Human Thermal Comfort

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Índices de (des) conforto humano em um município de clima semiárido

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v13.07.p3287-3303 ◽

2020 ◽

Vol 13 (07) ◽

pp. 3287

Author(s):

Rebecca Luna Lucena ◽

Jório Bezerra Cabral Júnior ◽

Ercília Torres Steinke

Keyword(s):

Thermal Comfort ◽

Urban Climate ◽

Heat Island ◽

Temperature Index ◽

Human Thermal Comfort ◽

Data Loggers ◽

De Se ◽

Humidity Index ◽

Semi Arid ◽

Comfort Indices

O objetivo principal neste trabalho consistiu em analisar e comparar índices de (des) conforto térmico humano em um município de clima semiárido. Para isso foram adquiridos e utilizados equipamentos termo-higrômetros automáticos datalogger Akso AK170, sendo esses distribuídos espacialmente em onze pontos (dez em áreas urbanizadas e um em área rural), durante um período de 32 dias, em Caicó-RN. De posse dos dados horários de temperatura e umidade relativa do ar (maio/junho), realizaram-se análises estatísticas descritivas e aplicaram-se três índices de conforto humano, a saber: Índice de Desconforto (ID), índice de Temperatura Efetiva (TE), e o Índice de Temperatura e Umidade (ITU). Os resultados indicaram que o município de Caicó está propenso aos efeitos do processo de urbanização, registrando-se frequências de temperaturas mais elevadas nas áreas urbanizadas, especialmente nas de menor arborização e maior concentração de pavimentos urbanos. Em termos médios a maior parte da população de Caicó sente desconforto devido ao calor (ID), as temperaturas ficaram sempre acima do considerado calor moderado (TE) e de acordo com o ITU a classificação foi de extremamente desconfortável. Portanto, é imprescindível minimizar o os efeitos da ilha de calor no município a fim de se obter melhores índices de conforto térmico humano. Human (dis) comfort indices in a semi-arid municipality in Brazil A B S T R A C TThe main aim of this study was to analyse and compare the human thermal (dis)comfort indices in a Brazilian municipality with a semi-arid climate: Caicó, in the state of Rio Grande do Norte. Akso AK170 thermo-hygrometer data loggers were acquired for this purpose, which were distributed at eleven points in the study area – ten in built-up areas and one in a rural area – over a 32-day period covering the months of May to June. Having collected the time- and date-stamped temperature and relative humidity data, descriptive statistical analyses were conducted using three human comfort indices: discomfort index (DI), effective temperature index (ETI), and temperature-humidity index (THI). The results indicate that the municipality under study is affected by urbanization processes that propitiate higher temperatures in the built-up areas, especially where there are fewer trees and more of the roads are paved. On average, most of the population of Caicó feels discomfort because of the heat (ID), and the temperature always remains above the range rated as moderately hot (ETI). The municipal climate was classified as “extremely uncomfortable” by the THI. It is therefore of the utmost importance to minimize the effects of the heat island in the municipality to improve the human thermal comfort indices.Keywords: Urban climate. Caicó-RN. Human thermal comfort indices.

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