Evaluation of urban heat islands using local climate zones and the influence of sea-land breeze

The effect of urban development on local thermal climate is widely documented in scientific literature. Observations of urban–rural air temperature differences—or urban heat islands (UHIs)—have been reported for cities and regions worldwide, often with local field sites that are extremely diverse in their physical and climatological characteristics. These sites are usually described only as “urban” or “rural,” leaving much uncertainty about the actual exposure and land cover of the sites. To address the inadequacies of urban–rural description, the “local climate zone” (LCZ) classification system has been developed. The LCZ system comprises 17 zone types at the local scale (102 to 104 m). Each type is unique in its combination of surface structure, cover, and human activity. Classification of sites into appropriate LCZs requires basic metadata and surface characterization. The zone definitions provide a standard framework for reporting and comparing field sites and their temperature observations. The LCZ system is designed primarily for urban heat island researchers, but it has derivative uses for city planners, landscape ecologists, and global climate change investigators.

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Using “Local Climate Zones” to Detect Urban Heat Island on Two Small Cities in Alabama

Earth Interactions ◽

10.1175/ei-d-17-0020.1 ◽

2018 ◽

Vol 22 (16) ◽

pp. 1-22 ◽

Cited By ~ 3

Author(s):

Jeff Chieppa ◽

Austin Bush ◽

Chandana Mitra

Keyword(s):

Classification System ◽

Urban Climate ◽

Urban Heat Islands ◽

Small Cities ◽

Local Climate ◽

Heat Islands ◽

Hourly Temperature ◽

Rural Environments ◽

Local Climate Zones ◽

Urban Heat

Abstract Classifying “urban” and “rural” environments is a challenge in understanding urban climate, specifically urban heat islands (UHIs). Stewart and Oke developed the “local climate zone” (LCZ) classification system to clarify these distinctions using 17 unique groups. This system has been applied to many areas around the world, but few studies have attempted to utilize them to detect UHI effects in smaller cities. Our aim was to use the LCZ classification system 1) to detect UHI in two small cities in Alabama and 2) to determine whether similar zones experienced similar intensity or magnitude of UHIs. For 1 week, we monitored hourly temperature in two cities, in four zones: compact low-rise, open low-rise, dense forests, and water. We found that urban zones were often warmer for overall, daytime, and nighttime temperatures relative to rural zones (from −0.1° to 2.8°C). In addition, we found that temperatures between cities in similar zones were not very similar, indicating that the LCZ system does not predict UHI intensity equally in places with similar background climates. We found that the LCZ classification system was easy to use, and we recognize its potential as a tool for urban ecologists and urban planners.

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Advances of Local Climate Zone Mapping and Its Practice Using Object-Based Image Analysis

Atmosphere ◽

10.3390/atmos12091146 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1146

Author(s):

Lei Ma ◽

Xiaoxiang Zhu ◽

Chunping Qiu ◽

Thomas Blaschke ◽

Manchun Li

Keyword(s):

Image Analysis ◽

Urban Heat Islands ◽

Local Climate ◽

Heat Islands ◽

Object Based Image Analysis ◽

Object Based ◽

Local Climate Zones ◽

Urban Heat ◽

Future Object ◽

Local Climate Zone

In the context of climate change and urban heat islands, the concept of local climate zones (LCZ) aims for consistent and comparable mapping of urban surface structure and cover across cities. This study provides a timely survey of remote sensing-based applications of LCZ mapping considering the recent increase in publications. We analyze and evaluate several aspects that affect the performance of LCZ mapping, including mapping units/scale, transferability, sample dataset, low accuracy, and classification schemes. Since current LCZ analysis and mapping are based on per-pixel approaches, this study implements an object-based image analysis (OBIA) method and tests it for two cities in Germany using Sentinel 2 data. A comparison with a per-pixel method yields promising results. This study shall serve as a blueprint for future object-based remotely sensed LCZ mapping approaches.

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Local climate zones in the city of Nur-Sultan (Kazakhstan) and their connections with urban heat island and thermal comfort

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/611/1/012060 ◽

2020 ◽

Vol 611 ◽

pp. 012060

Author(s):

A A Berlessova ◽

P I Konstantinov

Keyword(s):

Thermal Comfort ◽

Urban Heat Island ◽

Heat Island ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Urban Heat ◽

The City

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Dynamic Changes of Local Climate Zones in the Guangdong–Hong Kong–Macao Greater Bay Area and Their Spatio-Temporal Impacts on the Surface Urban Heat Island Effect between 2005 and 2015

Sustainability ◽

10.3390/su13116374 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6374

Author(s):

Yang Lu ◽

Jiansi Yang ◽

Song Ma

Keyword(s):

Hong Kong ◽

Land Surface ◽

Morphological Changes ◽

Mapping Method ◽

Heat Radiation ◽

Climate Zones ◽

Local Climate ◽

Bay Area ◽

Local Climate Zones ◽

Urban Heat

Local climate zones (LCZs) emphasize the influence of representative geometric properties and surface cover characteristics on the local climate. In this paper, we propose a multi-temporal LCZ mapping method, which was used to obtain LCZ maps for 2005 and 2015 in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA), and we analyze the effects of LCZ changes in the GBA on land surface temperature (LST) changes. The results reveal that: (1) The accuracy of the LCZ mapping of the GBA for 2005 and 2015 is 85.03% and 85.28%, respectively. (2) The built type category showing the largest increase in area from 2005 to 2015 is LCZ8 (large low-rise), with a 1.01% increase. The changes of the LCZs also vary among the cities due to the different factors, such as the economic development level and local policies. (3) The area showing a warming trend is larger than the area showing a cooling trend in all the cities in the GBA study area. The main reasons for the warming are the increase of built types, the enhancement of human activities, and the heat radiation from surrounding high-temperature areas. (4) The spatial morphology changes of the built type categories are positively correlated with the LST changes, and the morphological changes of the LCZ4 (open high-rise) and LCZ5 (open midrise) built types exert the most significant influence. These findings will provide important insights for urban heat mitigation via rational landscape design in urban planning management.

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Multitemporal Landsat data for urban heat island assessment and classification of local climate zones

2011 Joint Urban Remote Sensing Event ◽

10.1109/jurse.2011.5764736 ◽

2011 ◽

Cited By ~ 14

Author(s):

Benjamin Bechtel

Keyword(s):

Urban Heat Island ◽

Heat Island ◽

Landsat Data ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Urban Heat

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LINKING THE LOCAL CLIMATE ZONES AND LAND SURFACE TEMPERATURE TO INVESTIGATE THE SURFACE URBAN HEAT ISLAND, A CASE STUDY OF SAN ANTONIO, TEXAS, U.S.

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-3-277-2018 ◽

2018 ◽

Vol IV-3 ◽

pp. 277-283 ◽

Cited By ~ 4

Author(s):

Chunhong Zhao

Keyword(s):

Surface Temperature ◽

Urban Heat Island ◽

Land Surface Temperature ◽

Land Surface ◽

San Antonio ◽

Heat Island ◽

Climate Zones ◽

Local Climate ◽

Local Climate Zones ◽

Urban Heat

The Local Climate Zones (LCZs) concept was initiated in 2012 to improve the documentation of Urban Heat Island (UHI) observations. Despite the indispensable role and initial aim of LCZs concept in metadata reporting for atmospheric UHI research, its role in surface UHI investigation also needs to be emphasized. This study incorporated LCZs concept to study surface UHI effect for San Antonio, Texas. LCZ map was developed by a GIS-based LCZs classification scheme with the aid of airborne Lidar dataset and other freely available GIS data. Then, the summer LST was calculated based Landsat imagery, which was used to analyse the relations between LST and LCZs and the statistical significance of the differences of LST among the typical LCZs, in order to test if LCZs are able to efficiently facilitate SUHI investigation. The linkage of LCZs and land surface temperature (LST) indicated that the LCZs mapping can be used to compare and investigate the SUHI. Most of the pairs of LCZs illustrated significant differences in average LSTs with considerable significance. The intra-urban temperature comparison among different urban classes contributes to investigate the influence of heterogeneous urban morphology on local climate formation.

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