scholarly journals The Social Restrictions Impact on Urban Heat Island Phenomena (Case Study: Cities in Java Island)

2021 ◽  
Vol 887 (1) ◽  
pp. 012017
Author(s):  
A. M. Agni ◽  
P. Pangi ◽  
B. Septiarani ◽  
K. D. Astuti

Abstract The Coronavirus Disease 2019 (Covid-19) pandemic has hit Indonesia since March 14, 2020. The rapid spread of the virus has caused the central and regional governments to implement community activity policies. Some terms and methods used by local governments such as PSBB (the Large-Scale Social Restrictions) are applied in Special Capital Region of Jakarta and Surabaya City, in Semarang City has PKM (Restrictions on Community Activities). This study aims to analyze the impact of the social restrictions on Urban Heat Island (UHI) in the Java Island big city. This research was conducted in big cities on Java Island that apply social restrictions, namely Special Capital Region of Jakarta, Bandung, Semarang, Yogyakarta, Surakarta, Surabaya, and Malang. The data used are Landsat 8 satellite imagery in 2019 and 2020. The method used is to compare the magnitude of the Land Surface Temperature (LST) and UHI before and after social restrictions. The results of the analysis explain that there is a decrease in LST and changes in UHI in the cities of Special Capital Region of Jakarta, Bandung, Semarang, Surakarta, and Yogyakarta. However, in Surabaya and Malang, there was an increase in LST. This study concludes that the implementation of social restrictions affects changes in UHI and decreases LST.

2020 ◽  
Vol 12 (3) ◽  
pp. 578
Author(s):  
Yuchen Wang ◽  
Yu Zhang ◽  
Nan Ding ◽  
Kai Qin ◽  
Xiaoyan Yang

As an important energy absorption process in the Earth’s surface energy balance, evapotranspiration (ET) from vegetation and bare soil plays an important role in regulating the environmental temperatures. However, little research has been done to explore the cooling effect of ET on the urban heat island (UHI) due to the lack of appropriate remote-sensing-based estimation models for complex urban surface. Here, we apply the modified remote sensing Penman–Monteith (RS-PM) model (also known as the urban RS-PM model), which has provided a new regional ET estimation method with the better accuracy for the urban complex underlying surface. Focusing on the city of Xuzhou in China, ET and land surface temperature (LST) were inversed by using 10 Landsat 8 images during 2014–2018. The impact of ET on LST was then analyzed and quantified through statistical and spatial analyses. The results indicate that: (1) The alleviating effect of ET on the UHI was stronger during the warmest months of the year (May–October) but not during the colder months (November–March); (2) ET had the most significant alleviating effect on the UHI effect in those regions with the highest ET intensities; and (3) in regions with high ET intensities and their surrounding areas (within a radius of 150 m), variation in ET was a key factor for UHI regulation; a 10 W·m−2 increase in ET equated to 0.56 K decrease in LST. These findings provide a new perspective for the improvement of urban thermal comfort, which can be applied to urban management, planning, and natural design.


2021 ◽  
Author(s):  
Kazi Jihadur Rashid ◽  
Sumaia Islam ◽  
Mohammad Atiqur Rahman

Abstract Urban heat island (UHI) is one of the major causes for deteriorating ecology of the rapidly expanding Dhaka city in the changing climatic conditions. Although researchers have identified, characterized and modeled UHI in the study area, the ecological evaluation of UHI effect has not yet been focused. This study uses land surface normalization techniques such as urban thermal field variance (UTFVI) to quantify the impact of UHI and also identifies vulnerable UHI areas compared to land cover types. Landsat imageries from 1990 to 2020 were used at decadal intervals. Results of the study primarily show that intensified UHI areas have increased spatially from 33.1–40.9% in response to urban growth throughout the period of 1990 to 2020. Extreme surface temperature values above 31°C have also been shown in open soils in under-construction sites for future developmental purposes. UTFVI is categorized into six categories representing UHI intensity in relation to ecological conditions. Finally, comparative analysis between land use/land cover (LULC) with UTFVI shows that the ecological conditions deteriorate as the intensity of UHI increases in the area. The developed areas facing ecological threat have increased from 9.3–19.8% throughout the period. Effective mitigating measures such as increasing green surfaces and planned urbanization practices are crucial in this regard. This study would help policymakers to concentrate on controlling thermal exposure and on preserving sustainable urban life.


2017 ◽  
Vol 11 (2) ◽  
pp. 141-150 ◽  
Author(s):  
Paul Macarof ◽  
Florian Statescu

Abstract This study compares the normalized difference built-up index (NDBI) and normalized difference vegetation index (NDVI) as indicators of surface urban heat island effects in Landsat-8 OLI imagery by investigating the relationships between the land surface temperature (LST), NDBI and NDVI. The urban heat island (UHI) represents the phenomenon of higher atmospheric and surface temperatures occurring in urban area or metropolitan area than in the surrounding rural areas due to urbanization. With the development of remote sensing technology, it has become an important approach to urban heat island research. Landsat data were used to estimate the LST, NDBI and NDVI from four seasons for Iasi municipality area. This paper indicates than there is a strong linear relationship between LST and NDBI, whereas the relationship between LST and NDVI varies by season. This paper suggests, NDBI is an accurate indicator of surface UHI effects and can be used as a complementary metric to the traditionally applied NDVI.


Author(s):  
D. Gerçek ◽  
İ. T. Güven ◽  
İ. Ç. Oktay

Along with urbanization, sealing of vegetated land and evaporation surfaces by impermeable materials, lead to changes in urban climate. This phenomenon is observed as temperatures several degrees higher in densely urbanized areas compared to the rural land at the urban fringe particularly at nights, so-called Urban Heat Island. Urban Heat Island (UHI) effect is related with urban form, pattern and building materials so far as it is associated with meteorological conditions, air pollution, excess heat from cooling. UHI effect has negative influences on human health, as well as other environmental problems such as higher energy demand, air pollution, and water shortage. <br><br> Urban Heat Island (UHI) effect has long been studied by observations of air temperature from thermometers. However, with the advent and proliferation of remote sensing technology, synoptic coverage and better representations of spatial variation of surface temperature became possible. This has opened new avenues for the observation capabilities and research of UHIs. <br><br> In this study, "UHI effect and its relation to factors that cause it" is explored for İzmit city which has been subject to excess urbanization and industrialization during the past decades. Spatial distribution and variation of UHI effect in İzmit is analysed using Landsat 8 and ASTER day & night images of 2015 summer. Surface temperature data derived from thermal bands of the images were analysed for UHI effect. Higher temperatures were classified into 4 grades of UHIs and mapped both for day and night. <br><br> Inadequate urban form, pattern, density, high buildings and paved surfaces at the expanse of soil ground and vegetation cover are the main factors that cause microclimates giving rise to spatial variations in temperatures across cities. These factors quantified as land surface/cover parameters for the study include vegetation index (NDVI), imperviousness (NDISI), albedo, solar insolation, Sky View Factor (SVF), building envelope, distance to sea, and traffic space density. These parameters that cause variation in intra-city temperatures were evaluated for their relationship with different grades of UHIs. Zonal statistics of UHI classes and variations in average value of parameters were interpreted. The outcomes that highlight local temperature peaks are proposed to the attention of the decision makers for mitigation of Urban Heat Island effect in the city at local and neighbourhood scale.


2020 ◽  
Vol 12 (3) ◽  
pp. 1171 ◽  
Author(s):  
Hongyu Du ◽  
Fengqi Zhou ◽  
Chunlan Li ◽  
Wenbo Cai ◽  
Hong Jiang ◽  
...  

In the trend of global warming and urbanization, frequent extreme weather influences the life of citizens seriously. Shanghai, as a typical mega-city in China that has been successful in urbanization, suffers seriously from the urban heat island (UHI) effect. The research concentrates on the spatial and temporal pattern of surface UHI and land use. Then, the relation between them are further discussed. The results show that for the last 15 years, the UHI effect of Shanghai has been increasing continuously in both intensity and area. The UHI extends from the city center toward the suburban area. Along with the year, the ratio in area of Agricultural Land (AL), Wetland (WL), and Bare Land (BL) has decreased. On the contrary, Construction Land (CL) and Green Land (GL) have increased. The average land surface temperature (LST) rankings for each research year from high to low were all CL, BL, GL, AL, and WL. CL contributed the most to the UHI effect, while WL and GL contributed the most to mitigate the UHI. The conclusion provides practical advice aimed to mitigate the UHI effect for urban planning authorities.


Land ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 57 ◽  
Author(s):  
Huawei Li ◽  
Guifang Wang ◽  
Guohang Tian ◽  
Sándor Jombach

The Urban Heat Island (UHI) effect has been extensively studied as a global issue. The urbanization process has been proved to be the main reason for this phenomenon. Over the past 20 years, the built-up area of Zhengzhou city has grown five times larger, and the UHI effect has become increasingly pressing for the city’s inhabitants. Therefore, mitigating the UHI effect is an important research focus of the expanding capital city of the Henan province. In this study, the Landsat 8 image of July 2019 was selected from Landsat collection to obtain Land Surface Temperature (LST) by using Radiative Transfer Equation (RTE) method, and present land cover information by using spectral indices. Additionally, high-resolution Google Earth images were used to select 123 parks, grouped in five categories, to explore the impact factors on park cooling effect. Park Cooling Intensity (PCI) has been chosen as an indicator of the park cooling effect which will quantify its relation to park patch metrics. The results show that: (1) Among the five studied park types, the theme park category has the largest cooling effect while the linear park category has the lowest cooling effect; (2) The mean park LST and PCI of the samples are positively correlated with the Fractional Vegetation Cover (FVC) and with Normalized Difference Water Index (NDWI), but these are negatively correlated with the Normalized Difference Impervious Surface Index (NDISI). We can suppose that the increase of vegetation cover rate within water areas as well as the decrease of impervious surface in landscape planning and design will make future parks colder. (3) There is a correlation between the PCI and the park characteristics. The UHI effect could be mitigated by increasing of park size and reducing park fractal dimension (Frac_Dim) and perimeter-area ratio (Patario). (4) The PCI is influenced by the park itself and its surrounding area. These results will provide an important reference for future urban planning and urban park design to mitigate the urban heat island effect.


Author(s):  
Van Tran Thi ◽  
Bao Ha Duong Xuan ◽  
Mai Nguyen Thi Tuyet

In urban area, one of the great problem is the rise of temperature, which leads to form the urban heat island effect. This paper refers to the trend of the urban surface temperature extracted from the Landsat images from which to consider changes in the formation of surface urban heat island for the north of Ho Chi Minh city in period 1995-2015. Research has identified land surface temperature from thermal infrared band, according to the ability of the surface emission based on characteristics of normalized difference vegetation index NDVI. The results showed that temperature fluctuated over the city with a growing trend and the gradual expansion of the area of the high-temperature zone towards the suburbs. Within 20 years, the trend of the formation of surface urban heat island with two typical locations showed a clear difference between the surface temperature of urban areas and rural areas with space expansion of heat island in 4 times in 2015 compared to 1995. An extreme heat island located in the inner city has an area of approximately 18% compared to the total area of the region. Since then, the solution to reduce the impact of urban heat island has been proposed, in order to protect the urban environment and the lives of residents in Ho Chi Minh City becoming better


2018 ◽  
Vol 19 (1) ◽  
pp. 31
Author(s):  
Adenan Yandra Nofrizal

Pembangunan yang terjadi di Kota Solok akan menyebabkan terjadinya perubahan penggunaan lahan. Perubahan penggunaan lahan yang terjadi dengan meningkatnya lahan terbangun akan menyebabkan naiknya suhu permukaan (surface temperature) yang dapat menyebabkan terjadinya urban heat island. Penelitian ini bertujuan untuk mengetahui suhu permukaan yang ada di Kota Solok dan daerah fenomena urban heat island dan hubungan antara perubahan penggunaan lahan terhadap suhu permukaan yang menyebabkan terjadinya urban heat island di daerah Kota Solok. Metode yang digunakan dalam penelitian ini yaitu dengan menggunakan salah satu model Land Surface Temperature untuk mengetahui suhu permukaan dengan menggunakan aplikasi pengolahan citra digital selain itu juga menggunakan metode Object Base Image Analyst (OBIA) untuk mendapatkan penggunaan lahan yang ada di Kota Solok. Dengan menggunakan metode yang digunakan akan didapatkan suhu permukaan yang ada di Kota Solok dan daerah fenomena Urban Heat Island serta hubungannya penggunaan lahan dengan suhu permukaan.Kata Kunci : Suhu Permukaan, OBIA, Penggunaan Lahan


Author(s):  
Safdar Ali Shirazi ◽  
Khadija Shakrullah ◽  
Saadia Sultan Wahla ◽  
Mareena Khurshid

The aim of present study is to evaluate and assess the impact of built-up areas on development of the urbanheat island (UHI).The study mainly focused on Lahore, which is one of the mega cities of Pakistan. In terms ofpopulation size, Lahore is the second largest city of Pakistan with 11.13 million inhabitants. The geospatial techniques(Remote Sensing and Geographical Information System) along with statistical applications were applied to find out theLand Cover Land Uses changes and consequent development of builtup areas over the period of 2000 and 2015. Tostudy the UHI, the meteorological data of each 30 minutes for 36 days starting from 30th June 2015 to 4th August 2015were collected through direct on site observation by using digital weather station. The results of UHI were crosschecked by obtaining land surface temperature by using thermal infrared (TIR) band 6 of the Landsat-7 TM. The resultsshow that the LCLU and built environment have direct impact on development of UHI. The areas where there wasmore vegetation cover had less temperature while in urban areas, the temperature was measured higher. Over the periodof 36 days, the average UHI remained 5.5°C and the highest intensity of UHI was observed as 8.3°C thus augmentedresearch rationale. The study suggests establishment of a thick network of automatic weather stations in Lahore togauge the urban heat island intensity and to plant indigenous trees on vacant swaths and develop urban forest tomitigate city’s rising temperature.


2020 ◽  
Vol 22 (2) ◽  
pp. 71
Author(s):  
A Sediyo Adi Nugraha ◽  
Dewa Made Atmaja

Fenomena <em>Urban Heat Island </em>(UHI) sering dipengaruhi oleh kepadatan penduduk dan perubahan penggunaan lahan. Perubahan tesebut memiliki hubungan dengan peningkatan suhu permukaan (<em>Land Surface Temperature</em>/LST) sebagai awal terjadinya UHI. Deteksi perubahan penggunaan lahan dan suhu permukaan dilakukan dari tahun 2000, 2010, dan 2018 pada daerah Kabupaten Buleleng dan berfokus pada Kecamatan Buleleng karena memiliki perubahan lahan terbangun lebih cepat dibandingkan kecamatan lain. Tujuannya untuk mengetahuii bagaimana fenomena UHI itu terjadi akibat dari perubahan penggunaan lahan. Selain itu, seberapa besar peningkatan suhu permukaan selama 18 tahun khususnya di Kecamatan Buleleng dengan mengetahui kondisi ditribusi dan intensitas UHI. Metode yang digunakan dalam deteksi UHI menggunakan citra penginderaan jauh multi-temporal yaitu citra Landsat 7 ETM+ dan citra Landsat 8 OLI/TIRS (<em>The Operational Land Imager and the Thermal Infrared Scanner</em>) sebagai data primer. Pengolahan data akan berfokus pada ekstraksi suhu permukaan dengan metode <em>Split-Windows Algorithm Sobrino </em>(SWA-S) untuk Landsat 8 dan metode <em>Brightness Temperature Emissivity Correction</em> untuk Landsat 7, kemudian <em>Maximum Likelihood</em> sebagai metode penggunaan lahan. Hasil pengolahan menunjukkan bahwa penggunaan metode yang berbeda memberikan dampak terhadap fenomena UHI. Perbedaan suhu selama 18 tahun sebesar sebesar ±5°C hal itu dipengaruhi dari kondisi awan dan bayangan. Perubahan penggunaan lahan dari tahun 2000 hingga 2018 terdapat peningkatan lahan terbangun di Kecamatan Buleleng dan peningkatan suhu permukan sebesar 2°-7°C dari lahan terbangun. Fenomena UHI untuk distribusi dan instensitas UHI terjadi di daerah pusat perkotaan dan kenaikan intensitas UHI sebesar 1.75°C. kesimpulannya bahwa perubahan lahan terbangun memberikan dampak kenaikan suhu permukaan dan menyebabkan fenomena UHI.


Sign in / Sign up

Export Citation Format

Share Document