Modelled spatiotemporal variability of outdoor thermal comfort in local climate zones of the city of Brno, Czech Republic

Urban areas show higher nocturnal temperature comparing to rural areas, which is denoted by urban heat island. This effect can intensify the impact of global warming in urban areas especially during heat waves, that leads to higher energy demand for cooling the building and higher thermal stress for residents.&#160;&#160;The aim of this study is to identify the Urban Heat Island (UHI) effect during the heat spell 2018 and 2019 in order to calculated human thermal comfort for Berlin. Berlin, the capital city of Germany covers an area of 892km2 and its population is growing, therefore more residential areas will be planned in future through higher building. The methodology of this research is to divide Berlin into Local Climate Zones (LCZ's) regarding the concept of Stewart & Oke (2012). Then to evaluate the accuracy of this concept using 30 microclimate stations. Estimating the magnitude of urban heat island and its seasonal changes in combination with human thermal perception in different LCZ during summer time is another objective of this research.&#160;Ten LCZ's for Berlin were selected, as class 1 (compact high rise), class 3 (compact low rise), class 7 (lightweight low-rise), class C (bush, scrub), class E (bare rock or paved) and class F (bare soil or sand) don't exist in Berlin. Class A (dense trees) is with a fraction of 18.6% in a good agreement with the percentage of dense trees reported from the city administration of Berlin (18.4%), class G (water) has a coverage of 5.1% through our classification instead of 6.7% reported by the city administration. In summary, the LCZ 1-10 cover 59.3% (more than half) of the city area.Regarding temperature measurements, which represent a hot summer day with calm wind and clear sky the difference of Local Climate Zones will be calculated and the temperature variability in every LCZ's regarding sky view factor values show the hot spot of the city.The vulnerability of LCZ's to heat stress will be ranked and discussed regarding ventilation and other factors.&#160;LiteratureMatzarakis, A. Mayer, H., Iziomon, M. (1999) Applications of a universal thermal index: Physiological equivalent temperature: Intern. J. of Biomet 43 (2), 76-84.Stewart, I.D., Oke, T.R. (2012) Local climate zones for urban temperature studies. Bull. Amer. Meteor. Soc. 93 1879-1900. DOI: 10.1175/BAMS-D-11-00019.1.&#160;

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Urban tree planting to maintain outdoor thermal comfort under climate change: The case of Vancouver's local climate zones

Building and Environment ◽

10.1016/j.buildenv.2019.05.022 ◽

2019 ◽

Vol 158 ◽

pp. 226-236 ◽

Cited By ~ 11

Author(s):

Mehdi Aminipouri ◽

David Rayner ◽

Fredrik Lindberg ◽

Sofia Thorsson ◽

Anders Jensen Knudby ◽

...

Keyword(s):

Climate Change ◽

Thermal Comfort ◽

Tree Planting ◽

Outdoor Thermal Comfort ◽

Climate Zones ◽

Local Climate ◽

Urban Tree ◽

Local Climate Zones

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Local Climate Zones Definition in Relation to ENVI-met in the City of Dubai, UAE.

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/829/1/012013 ◽

2020 ◽

Vol 829 ◽

pp. 012013

Author(s):

Lindita Bande ◽

Prajowal Manandhar ◽

Prashanth Marpu ◽

Mohammad Al Battah

Keyword(s):

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

The City

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A Study of Local Climate Zones in Abu Dhabi with Urban Weather Stations and Numerical Simulations

Sustainability ◽

10.3390/su12010156 ◽

2019 ◽

Vol 12 (1) ◽

pp. 156 ◽

Cited By ~ 1

Author(s):

Prajowal Manandhar ◽

Lindita Bande ◽

Alexandros Tsoupos ◽

Prashanth Reddy Marpu ◽

Peter Armstrong

Keyword(s):

Numerical Simulations ◽

Abu Dhabi ◽

Thermal Dynamics ◽

Climate Zones ◽

Local Climate ◽

Heat Flows ◽

Local Climate Zones ◽

Urban Heat ◽

Landsat Satellite ◽

The City

In many cities that have experienced rapid growth like Abu Dhabi, urban microclimate scenarios evolve rapidly as well and it is important to study the urban thermal dynamics continuously. The Local Climate Zone (LCZ) classification considers factors related to the physical properties like surface cover and surface structure of the city which allow to analyze urban heat flows. Abu Dhabi city is rapidly expanding and is characterized by highly heterogeneous types of built forms that comprise mainly of old mid-rise and modern high-rise buildings with varied degrees of vegetation cover in different parts of the city. The fact that it is a coastal city in a desert environment makes it quite unique. This paper presents an approach of studying urban heat flows in such heterogeneous setup. First, the city is classified into local climate zones using images acquired by Landsat Satellite. Numerical simulations are performed in the designated LCZs using a computational fluid dynamics software, Envi-met. The results of Envi-met are calibrated and validated using in-situ measurements across all four seasons. The calibrated models are then applied to study entire Abu Dhabi island across different seasons. The results indicate a clear presence of urban heat island (UHI) effect when averaged over the full day which is varying in different zones. The zones with high vegetation do not show large average UHI effect whereas the effect is significant in densely built zones. The study also validates previous observations on the inversion of UHI effect during the day and in terms of diurnal response.

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Sea Breeze Front and Outdoor Thermal Comfort during Summer in Northeastern Brazil

Atmosphere ◽

10.3390/atmos11091013 ◽

2020 ◽

Vol 11 (9) ◽

pp. 1013

Author(s):

Max Anjos ◽

António Lopes ◽

Andrews José de Lucena ◽

Francisco Mendonça

Keyword(s):

Heat Stress ◽

Thermal Comfort ◽

Meteorological Data ◽

Sea Breeze ◽

Weather Conditions ◽

Northeastern Brazil ◽

Outdoor Thermal Comfort ◽

Physiological Equivalent Temperature ◽

Local Climate ◽

Local Climate Zones

Characterizing the behaviour of the sea breeze phenomenon is the foremost factor in the reduction in the heat stress and the achievement of the pleasant environment in coastal cities globally. However, this seminal study shows that the Sea Breeze Front (SBF) development can be related to an increase in outdoor thermal discomfort in a northeastern Brazilian city during summer. We explored the relationship between SBF and thermal comfort conditions using in situ meteorological observations, the SBF identification method, local climate zones (LCZs) classification, and the Physiological Equivalent Temperature (PET) thermal comfort index. SBF days and Non-SBF days were characterized in terms of weather conditions, combining meteorological data and technical bulletins. SBF days included hot and sunny days associated with the centre of the Upper Tropospheric Cyclonic Vortices (UTCV). In contrast, Non-SBF days were observed in UTCV’s periphery because of cloudy sky and rainfall. The results showed that the mean temperature and PET in the SBF days were 2.0 °C and 3.8 °C higher, respectively, compared to Non-SBF days in all LCZ sites. The highest PET, of 40.0 °C, was found on SBF days. Our findings suggest that SBF development could be an aggravating factor for increasing heat stress of the people living in the northeastern coast of the Brazilian city, after SBF passage.

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Comparison of urban climate measurements in Berlin and LES model output for a special observation period

10.5194/egusphere-egu21-2194 ◽

2021 ◽

Author(s):

Ines langer ◽

Alexander Pasternack ◽

Uwe Ulbrich ◽

Henning Rust

Keyword(s):

Mean Square Error ◽

Urban Climate ◽

Specific Humidity ◽

Mean Square ◽

Climate Zones ◽

Local Climate ◽

Large Eddy Simulation Model ◽

Local Climate Zones ◽

The City ◽

Observation Period

Surface (2 m) temperature and specific humidity data are measured at 5-minute intervals in a network comprising 33 stations distributed across the city of Berlin, Germany. These data are utilized in order to validate a LES (large eddy simulation) model designed to assess the local climate at a very high resolution of 10 m to 1 m. This model, was developed at the &#8203;Institute of Meteorology and Climatology (IMUK) of the Leibniz Universit&#228;t Hannover, Germany, and is developed into an application tool for city planners within the funding programme "[UC&#178;] - Urban Climate under Change", of the German Federal Ministry of Education and Research (BMBF).The evaluation distinguishes between the different Local climate zones (LCZ) in the city, which are defined following the concept of Stewart & Oke (2012). For Berlin, the following LCZ have been identified: 2 (compact midrise), 4 (open high-rise), 6 (open low-rise), 8 (large low-rise), A (dense trees), B (scattered trees), D (low Plants), G (water).We analyzed one cold winter day during an intensive observation period from 06 UTC on 17th January to 06 UTC on 18th January, 2017. The minimum and maximum recorded temperatures were -8.1 &#176;C and +2 &#176;C, respectively, the sun shine duration was 6.5 hours. Daily and hourly mean absolute error, mean square error and root mean square error confirm that the deviation between measurements and the PALM-4U model differs between the LCZ for Berlin, with particularly large negative deviations of up to 5 K in forest areas, as they are not yet well represented in the model. Smallest deviations are found for the industrial zone. In all cases, the observed amplitude of the diurnal cycle is underestimated. The role of the driving model for the deviations found is addressed.Stewart, I.D., Oke, T.R. (2012) Local climate zones for urban temperature studies. Bull. Amer. Meteor. Soc. 93 1879-1900. DOI: 10.1175/BAMS-D-11-00019.1.&#160;

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Spatial modelling of summer climate indices based on local climate zones: expected changes in the future climate of Brno, Czech Republic

Climatic Change ◽

10.1007/s10584-018-2353-5 ◽

2019 ◽

Vol 152 (3-4) ◽

pp. 487-502 ◽

Cited By ~ 11

Author(s):

Jan Geletič ◽

Michal Lehnert ◽

Petr Dobrovolný ◽

Maja Žuvela-Aloise

Keyword(s):

Czech Republic ◽

Spatial Modelling ◽

Future Climate ◽

Climate Indices ◽

Climate Zones ◽

Local Climate ◽

Summer Climate ◽

Local Climate Zones ◽

The Future

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Mapping Local Climate Zones and Their Applications in European Urban Environments: A Systematic Literature Review and Future Development Trends

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10040260 ◽

2021 ◽

Vol 10 (4) ◽

pp. 260

Author(s):

Michal Lehnert ◽

Stevan Savić ◽

Dragan Milošević ◽

Jelena Dunjić ◽

Jan Geletič

Keyword(s):

Urban Areas ◽

Urban Climate ◽

Well Being ◽

Climatic Conditions ◽

Urban Environments ◽

Outdoor Thermal Comfort ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Scale Modelling

In the light of climate change and burgeoning urbanization, heat loads in urban areas have emerged as serious issues, affecting the well-being of the population and the environment. In response to a pressing need for more standardised and communicable research into urban climate, the concept of local climate zones (LCZs) has been created. This concept aims to define the morphological types of (urban) surface with respect to the formation of local climatic conditions, largely thermal. This systematic review paper analyses studies that have applied the concept of LCZs to European urban areas. The methodology utilized pre-determined keywords and five steps of literature selection. A total of 91 studies were found eligible for analysis. The results show that the concept of LCZs has been increasingly employed and become well established in European urban climate research. Dozens of measurements, satellite observations, and modelling outcomes have demonstrated the characteristic thermal responses of LCZs in European cities. However, a substantial number of the studies have concentrated on the methodological development of the classification process, generating a degree of inconsistency in the delineation of LCZs. Recent trends indicate an increasing prevalence of the accessible remote-sensing based approach over accurate GIS-based methods in the delineation of LCZs. In this context, applications of the concept in fine-scale modelling appear limited. Nevertheless, the concept of the LCZ has proven appropriate and valuable to the provision of metadata for urban stations, (surface) urban heat island analysis, and the assessment of outdoor thermal comfort and heat risk. Any further development of LCZ mapping appears to require a standardised objective approach that may be globally applicable.

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