Air temperature characteristics of local climate zones in the Augsburg urban area (Bavaria, southern Germany) under varying synoptic conditions

Local Climate Zones (LCZs) classification of urban area under World Urban Database and PortalTool (WUDAPT) framework has amassed about 100 regions’ LCZ catalog by an international collaborationof researchers. With Landsat 8 (L8) being the current standard of imagery for most of the LCZ classificationprocess, the question of ability to distinguish LCZs from the spectral range of L8 imagery need to be answered.Using sample of training areas, Jeffries-Matusita distance are computed as the measure of separability toinvestigate if any pairs of LCZ class consistently show similar spectral signature and it’s utility to predict thequality of final LCZ classification.

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Impact of Land Cover Composition and Structure on Air Temperature Based on the Local Climate Zone Scheme in Hangzhou, China

Atmosphere ◽

10.3390/atmos12080936 ◽

2021 ◽

Vol 12 (8) ◽

pp. 936

Author(s):

Hai Yan ◽

Shimin Yang ◽

Xiaohui Guo ◽

Fan Wu ◽

Renwu Wu ◽

...

Keyword(s):

Land Cover ◽

Air Temperature ◽

Temperature Difference ◽

Thermal Environment ◽

Urban Climate ◽

Rapid Urbanization ◽

Climate Zones ◽

Local Climate ◽

Composition And Structure ◽

Local Climate Zones

At present, conflicts between urban development and the climate environment are becoming increasingly apparent under rapid urbanization in China. Revealing the dynamic mechanism and controlling factors of the urban outdoor thermal environment is the necessary theoretical preparation for regulating and improving the urban climate environment. Taking Hangzhou as an example and based on the local climate zones classification system, we investigated the effects of land cover composition and structure on temperature variability at the local scale. The measurement campaign was conducted within four local climate zones (LCZ 2, 4, 5, and LCZ 9) during 7 days in the summer of 2018. The results showed that the temperature difference within the respective LCZ was always below 1.1 °C and the mean temperature difference between LCZs caused by different surface physical properties was as high as 1.6 °C at night. Among four LCZs, LCZ 2 was always the hottest, and LCZ 9 was the coolest at night. In particular, the percentage of pervious surface was the most important land cover feature in explaining the air temperature difference. For both daytime and nighttime, increasing the percentage of pervious surface as well as decreasing the percentage of impervious surface and the percentage of building surface could lower the local temperature, with the strongest influence radius range from 120 m to 150 m. Besides, the temperature increased with the SVF increased at day and opposite at night.

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Thermal properties based on air temperature observations in different local climate zones in Bogotá, Colombia

Climate Research ◽

10.3354/cr01619 ◽

2020 ◽

Vol 82 ◽

pp. 15-31

Author(s):

EA Ramírez-Aguilar ◽

LCL Souza

Keyword(s):

Thermal Properties ◽

Air Temperature ◽

Thermal Sensation ◽

Urban Morphology ◽

Early Application ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Temperature Observations ◽

The City

This paper demonstrates an early application of local climate zones (LCZs) in the city of Bogotá, Colombia. The main goal was to assess the thermal properties within the areas of influence (sectors) of 10 meteorological stations in the city, classified into the LCZ scheme. Air temperature observations at 07:00, 13:00 and 19:00 h (T7:00, T13:00 and T19:00) and daily measurements were obtained from the stations, and the maximum (Tmax), minimum (Tmin) and mean (Tmean) values were calculated. Their distribution and variation were analyzed, thermal sensation categories were calculated, and the thermal differences (ΔTLCZX-LCZD) between open-compact LCZ types and LCZD (typical rural type with low plants) were obtained in order to identify patterns between the stations and their assigned LCZs. Furthermore, we compared urban morphology (form) parameters to the ranges proposed in the literature to classify LCZs. The results clearly showed variations and patterns between the stations and their assigned LCZs when using Tmin, T7:00 and T19:00 air temperature data and the indices and categories calculated from these. Values of ΔTLCZX-LCZD > 5°C were found in the densely urbanised LCZ at night, and some negative values at noon suggested the presence of an urban cool island. The results show the usefulness of LCZs in understanding differences and temperature variations between divergent urban sectors. However, when different LCZ types are grouped, the thermal differences between them can be better appreciated and explained. The main conclusion is that the urban surface of Bogotá does not generate high temperatures, but decreases the occurrences of low values in Tmin, Tmean, T19:00 and T7:00.

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Mapping humidity plume over local climate zones in a high-altitude tropical climate city, Brazil

Ambiente Construído ◽

10.1590/s1678-86212018000400300 ◽

2018 ◽

Vol 18 (4) ◽

pp. 177-197 ◽

Cited By ~ 3

Author(s):

Erico Masiero ◽

Léa Cristina Lucas de Souza

Keyword(s):

Data Collection ◽

High Altitude ◽

Air Temperature ◽

Water Body ◽

Tropical Climate ◽

Urban Centre ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Cooling Effects

Abstract The aim of this research is to detect the cooling effects of water body evaporation in different Local Climate Zones (LCZs) in a tropical area. We attempted to register the humidity action over the urban environment caused by the evaporation of an urban lake according to the typical regional winds. The method was developed on the basis of three steps: the physical characterization of the LCZ conditions, the definition of data collection procedures with the mesoclimate analysis; and the interpretation of data by mapping the local measured variables. The study also included a microclimate data collection campaign aimed to evaluate more specifically the typical behaviour of the air temperature and absolute humidity in areas near the water body and in environments of the urban centre of São Jose do Rio Preto in Brazil. The air temperature range in areas near the water surface presented values lower than the denser areas, reaching differences close to 4 °C, and as the environment becomes drier and impermeable, the air temperature tended to be higher. This fact highlights the need to being outlined urban occupation strategies for improving the thermal quality of the built environment, mainly in cities located in regions with a predominantly high altitude tropical climate.

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Air Humidity Characteristics in “Local Climate Zones” of Novi Sad (Serbia) Based on Long-Term Data

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10120810 ◽

2021 ◽

Vol 10 (12) ◽

pp. 810

Author(s):

Jelena Dunjić ◽

Dragan Milošević ◽

Milena Kojić ◽

Stevan Savić ◽

Zorana Lužanin ◽

...

Keyword(s):

Vapor Pressure ◽

Air Temperature ◽

Temporal Dynamics ◽

Water Vapor Pressure ◽

Specific Humidity ◽

Air Humidity ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Novi Sad

This study aims to investigate spatial and temporal dynamics and relationship between air temperature and five air humidity parameters (relative humidity, water vapor pressure, absolute humidity, specific humidity, and vapor pressure deficit) in Novi Sad, Serbia, based on two-year data (Dec 2015–Dec 2017). The analysis includes different urban areas of Novi Sad, which are delineated in five built (urban) types of local climate zones (LCZ) (LCZ 2, LCZ 5, LCZ 6, LCZ 8, and LCZ 9), and one land cover (natural) local climate zone (LCZ A) located outside the urban area. Temporal analysis included annual, seasonal, and monthly dynamics of air temperature and air humidity parameters, as well as their patterns during the extreme periods (heat and cold wave). The results showed that urban dry island (UDI) occurs in densely urbanized LCZ 2 from February to October, unlike other urban LCZs. The analysis of the air humidity dynamics during the heat wave shows that UDI intensity is most pronounced during the daytime, but also in the evening (approximately until midnight) in LCZ 2. However, lower UDI intensity is observed in the afternoon, in other urban LCZs (LCZ 6, LCZ 8, and LCZ 9) and occasionally in the later afternoon in LCZ 5. Regression analysis confirms the relationship between air temperature and each of the analyzed air humidity parameters.

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