The Role of Vegetation in Controlling Air Temperature Resulting from Urban Heat Island

Urban Heat Island (UHI) is a phenomenon exhibited by many worldwide cities. Cities, which exhibit UHI, possess higher air temperature as compared with air temperature in the surrounding areas. However, existing UHI profiles are those occurring in subtropical areas which are, of course, very much different from those in tropical cities. Therefore, the objectives of this study are to describe the UHI’s profile and the role of tree vegetation in controlling and reducing air temperature in a tropical region’s urban areas and, particularly, in DKI Jakarta. In this study, we carried out a spatial analysis of land cover and the distribution of air temperature. In this regard, we based our analysis of the potency of tree vegetation in reducing air temperature in UHI’s profile on the distribution of air temperature in various types of land cover which extended from north to south and from east to west. The ranges of air temperature in land cover in the form of built-up areas were 29.2-39.5 ⁰C, non-tree vegetation 28.6-35.6 ⁰C, and tree vegetation 27.0-35.7 ⁰C. Accordingly, tree vegetation has the highest potential to reduce air temperature and to overcome the phenomenon of UHI.

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Can climate adaptation solutions fix the urban heat island? An assessment of the thermal conditions during heat waves in Vienna impacted by climate change and urban development scenarios for the mid-21st-century

10.5194/egusphere-egu2020-8668 ◽

2020 ◽

Author(s):

Paul Hamer ◽

Heidelinde Trimmel ◽

Philipp Weihs ◽

Stéphanie Faroux ◽

Herbert Formayer ◽

...

Keyword(s):

Climate Change ◽

Urban Heat Island ◽

Heat Wave ◽

Air Temperature ◽

Urban Areas ◽

Climate Adaptation ◽

Heat Waves ◽

Heat Island ◽

Human Thermal Comfort ◽

Urban Heat

Climate change threatens to exacerbate existing problems in urban areas arising from the urban heat island. Furthermore, expansion of urban areas and rising urban populations will increase the numbers of people exposed to hazards in these vulnerable areas. We therefore urgently need study of these environments and in-depth assessment of potential climate adaptation measures.We present a study of heat wave impacts across the urban landscape of Vienna for different future development pathways and for both present and future climatic conditions. We have created two different urban development scenarios that estimate potential urban sprawl and optimized development concerning future building construction in Vienna and have built a digital representation of each within the Town Energy Balance (TEB) urban surface model. In addition, we select two heat waves of similar frequency of return representative for present and future conditions (following the RCP8.5 scenario) of the mid 21st century and use the Weather Research and Forecasting Model (WRF) to simulate both heat wave events. We then couple the two representations urban Vienna in TEB with the WRF heat wave simulations to estimate air temperature, surface temperatures and human thermal comfort during the heat waves. We then identify and apply a set of adaptation measures within TEB to try to identify potential solutions to the problems associated with the urban heat island.Global and regional climate change under the RCP8.5 scenario causes the future heat wave to be more severe showing an increase of daily maximum air temperature in Vienna by 7 K; the daily minimum air temperature will increase by 2-4 K. We find that changes caused by urban growth or densification mainly affect air temperature and human thermal comfort local to where new urbanisation takes place and does not occur significantly in the existing central districts.Exploring adaptation solutions, we find that a combination of near zero-energy standards and increasing albedo of building materials on the city scale accomplishes a maximum reduction of urban canyon temperature of 0.9 K for the minima and 0.2 K for the maxima. Local scale changes of different adaption measures show that insulation of buildings alone increases the maximum wall surface temperatures by more than 10 K or the maximum mean radiant temperature (MRT) in the canyon by 5 K.&#160; Therefore, additional adaptation to reduce MRT within the urban canyons like tree shade are needed to complement the proposed measures.This study concludes that the rising air temperatures expected by climate change puts an unprecedented heat burden on Viennese inhabitants, which cannot easily be reduced by measures concerning buildings within the city itself. Additionally, measures such as planting trees to provide shade, regional water sensitive planning and global reduction of greenhouse gas emissions in order to reduce temperature extremes are required.We are now actively seeking to apply this set of tools to a wider set of cases in order to try to find effective solutions to projected warming resulting from climate change in urban areas.

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IDENTIFICATION OF URBAN HEAT ISLAND SPREADING TO CONCENTRATION OF NO2, O3, AND PM10 POLLUTANT IN DKI JAKARTA

Journal of Urban and Environmental Engineering ◽

10.4090/juee.2019.v13n1.125133 ◽

2019 ◽

pp. 125-133

Author(s):

Alfiyah Nur Fitriani ◽

Kania Dewi ◽

Laras Tursilowati

Keyword(s):

Land Cover ◽

Urban Heat Island ◽

Urban Areas ◽

Rapid Development ◽

Satellite Image ◽

Land Cover Changes ◽

Landsat 8 ◽

Heat Island ◽

Observation Area ◽

Urban Heat

Urban Heat Island is usually caused by Land use Land-Cover Changes (LULCC), including in Jakarta-Indonesia. Rapid development in Jakarta causes green open space to decrease and increase surface temperature in urban areas. In addition, Urban Heat Island also affects the spread of pollutants due to increased turbulence. Therefore, this study aims to find the link between temperature rise in DKI Jakarta which is influenced by land cover changes to pollutant spread such as NO2, PM10, and O3. This research begins with data processing observation of average temperature of DKI Jakarta area with meteorology station Tangerang, Banten for spatial calculation from year 2011-2016. In addition, LANDSAT 8 satellite image data is processed for spatial land and temperature encapsulation with Remote Sensing software from 2013-2015. As a result, in 2013 and 2015 there is a reduction in the area of vegetation that turns into non-vegetation (residential and industrial areas) that affect the temperature of the DKI Jakarta region is increasing. After that, sought the linkage between Urban Heat Island and the spread of pollutant concentrations in DKI Jakarta in 2013 and 2015. As a result, the increase of Jakarta area temperature, especially in pollutant observation area at five points, influenced the distribution of pollutant NO2, O3, and PM10 pollutant concentration balance with the dominan area such as roadside, industry, settlement in the time and area study in DKI Jakarta.

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A review of studies involving the effect of land cover and land use on the urban heat island phenomenon, assessed by means of the MUKLIMO model

Geografie ◽

10.37040/geografie2019124010083 ◽

2019 ◽

Vol 124 (1) ◽

pp. 83-101 ◽

Cited By ~ 1

Author(s):

Ján Feranec ◽

Monika Kopecká ◽

Daniel Szatmári ◽

Juraj Holec ◽

Pavel Šťastný ◽

...

Keyword(s):

Land Use ◽

Land Cover ◽

Urban Heat Island ◽

Urban Areas ◽

Rural Landscape ◽

Urban Heat Islands ◽

Urban Landscapes ◽

Heat Island ◽

Atmospheric Conditions ◽

Urban Heat

The urban heat island phenomenon occurs in urban areas. It is characterized by increased temperature of both the air and ground surface, compared to the surrounding rural landscape, and is a typical feature of the urban climate. As this phenomenon may affect quality of life in the cities, a variety of scientific studies have been carried out. The article provides a review and evaluation of selected published studies devoted to the issue of the urban heat island, from the point of view of the application of land cover and land use data in the 3-dimensional microscale urban model. Part of the review brings into focus the MUKLIMO model, which computes the atmospheric conditions in urban landscapes and predicts thermal and other climatic characteristics. Evaluated studies confirmed the correlation between the land cover/land use classes and occurrence of the urban heat islands, i.e. a higher percentage of impermeable surfaces within the urban heat island causes more intensive thermal manifestation. The urban heat island effect diminishes when there are less impermeable surfaces and a greater representation of urban greenery in land cover/land use classes.

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Cool Pavement Strategies for Urban Heat Island Mitigation in Suburban Phoenix, Arizona

Sustainability ◽

10.3390/su11164452 ◽

2019 ◽

Vol 11 (16) ◽

pp. 4452 ◽

Cited By ~ 7

Author(s):

Sushobhan Sen ◽

Jeffery Roesler ◽

Benjamin Ruddell ◽

Ariane Middel

Keyword(s):

Urban Heat Island ◽

Air Temperature ◽

Urban Areas ◽

Meteorological Data ◽

Heat Island ◽

Land Use Patterns ◽

Reflective Coating ◽

Air Temperatures ◽

Artificial Surfaces ◽

Urban Heat

Urban areas are characterized by a large proportion of artificial surfaces, such as concrete and asphalt, which absorb and store more heat than natural vegetation, leading to the Urban Heat Island (UHI) effect. Cool pavements, walls, and roofs have been suggested as a solution to mitigate UHI, but their effectiveness depends on local land-use patterns and surrounding urban forms. Meteorological data was collected using a mobile platform in the Power Ranch community of Gilbert, Arizona in the Phoenix Metropolitan Area, a region that experiences harsh summer temperatures. The warmest hour recorded during data collection was 13 August 2015 at 5:00 p.m., with a far-field air temperature of about 42 ∘ C and a low wind speed of 0.45 m/s from East-Southeast (ESE). An uncoupled pavement-urban canyon Computational Fluid Dynamics (CFD) model was developed and validated to study the microclimate of the area. Five scenarios were studied to investigate the effects of different pavements on UHI, replacing all pavements with surfaces of progressively higher albedo: New asphalt concrete, typical concrete, reflective concrete, making only roofs and walls reflective, and finally replacing all artificial surfaces with a reflective coating. While new asphalt surfaces increased the surrounding 2 m air temperatures by up to 0.5 ∘ C, replacing aged asphalt with typical concrete with higher albedo did not significantly decrease it. Reflective concrete pavements decreased air temperature by 0.2–0.4 ∘ C and reflective roofs and walls by 0.4–0.7 ∘ C, while replacing all roofs, walls, and pavements with a reflective coating led to a more significant decrease, of up to 0.8–1.0 ∘ C. Residences downstream of major collector roads experienced a decreased air temperature at the higher end of these ranges. However, large areas of natural surfaces for this community had a significant effect on downstream air temperatures, which limits the UHI mitigation potential of these strategies.

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STUDI PULAU PANAS PERKOTAAN DAN KAITANNYA DENGAN PERUBAHAN PARAMETER IKLIM SUHU DAN CURAH HUJAN MENGGUNAKAN CITRA SATELIT LANDSAT TM STUDI KASUS DKI JAKARTA DAN SEKITARNYA

Jurnal Sains & Teknologi Modifikasi Cuaca ◽

10.29122/jstmc.v13i1.2206 ◽

2012 ◽

Vol 13 (1) ◽

pp. 19 ◽

Cited By ~ 1

Author(s):

Halda Aditya Belgaman ◽

Sri Lestari ◽

Hilda Lestiana

Keyword(s):

Surface Temperature ◽

Urban Heat Island ◽

Air Temperature ◽

Urban Areas ◽

Satellite Image ◽

Heat Island ◽

Surrounding Area ◽

Urban Heat ◽

Climate Parameter ◽

Landsat Satellite

Pulau panas adalah suatu fenomena dimana suhu udara di suatu daerah lebih tinggi daripada suhu udara terbuka di sekitarnya. Daerah urban (perkotaan) sering mempunyai suhu lebih tinggi 1-6 derajat Celsius dibandingkan daerah sekitarnya (daerah pinggiran/ rural). Fenomena inilah yang dikenal sebagai ”Pulau Panas perkotaan” atau ”Urban Heat Island” (UHI). Penelitian ini bertujuan untuk mengetahui pengaruh fenomena pulau panas perkotaan terhadap parameter iklim terutama suhu dan curah hujan di daerahJakarta dan sekitarnya. Data yang digunakan pada tugas akhir ini adalah data curah hujan dan temperatur udara harian pada 5 stasiun pengamatan iklim, periode Januari 1991 – Desember 2001 sebagai data permukaan. Citra satelit Landsat 7 ETM+ path / row 122/064 akuisisi tanggal 15/07/2001 band 5,4,2 digunakan untuk menganalisis tutupan lahan dan band 6 digunakan untuk distribusi temperatur permukaan. Hasil menunjukkan nilai temperatur permukaan Kota Jakarta dan sekitarnya berada antara 15.07˚C hingga 33.28˚C. Lokasi pulau panas perkotaan terdapat di daerah Jakarta pusat dan Jakarta utara, dengan perbedaan temperatur sebesar 3˚C dibandingkan dengan daerah sekitarnya.Tutupan lahan yang terdapat di lokasi tersebut merupakan lahan terbangun yang terdiri dari bangunan perumahan, perkantoran, dan jalan raya. Perhitungan nilai korelasi Spearman antara data temperatur udara dari lima stasiun pengamatan dengan nilai piksel temperatur permukaan memperlihatkan adanya korelasi positif antara dua variabel tersebut yang ditunjukkan oleh indeks korelasi sebesar 0.6.Dengan persamaan regresi diperoleh citra temperatur permukaan di seluruh daerah pengamatan yang hasilnya menggambarkan bahwa lokasi pulau panas perkotaan sangat berpengaruh terhadap distribusi temperatur udara di atasnya.Heat island was a phenomenon where the temperature of air in one region higher than the temperature of the open air around it. Urban areas often had the temperature higher 1-6 Celsius when compared the area of surrounding area (the area of outskirts/rural). This phenomenon that was known as ”Pulau Panas Perkotaan” or ”Urban Heat Island” (UHI). This Research aimed to knowing influence of the heat islands of urban areas to climate parameter especially the temperature and the rainfall in the Jakarta and surrounding area. Data used in this research was rainfall data and daily air temperaturefrom 5 climate observation stations, within time period from January 1991 to December 2001 as the surface data. The Landsat satellite image 7 ETM+ path/row 122/064 acquisition date 15/07/2001, band 5, 4, 2 was used to analyze the cover of land and the band 6 was used for the distribution of surface temperature was based on the pixels value.Results showed the value of surface temperature in Jakarta and surrounding area was between 15.07˚C through to 33.28˚C. Location of heat island were in the centre Jakarta and north Jakarta, with the difference of the temperature as big as 3˚C with thesurrounding area. The land cover in this location were the housing building, the office complex, and the highway. Calculation of Spearman correlation value between the air temperature and surface temperature showed the existence of the positive correlation between two variables that it was demonstrated by the correlation index 0.6. From the regression equation we get the interpolated air temperature in Jakarta area.

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Urban Heat Island in Kathmandu, Nepal: Evaluating Relationship between NDVI and LST from 2000 to 2018

International Journal of Environment ◽

10.3126/ije.v8i1.22546 ◽

2019 ◽

Vol 8 (1) ◽

pp. 17-29

Author(s):

Bijesh Mishra ◽

Jeremy Sandifer ◽

Buddhi Raj Gyawali

Keyword(s):

Land Cover ◽

Urban Heat Island ◽

Land Surface ◽

Urban Areas ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Surface Characteristics ◽

Heat Island ◽

Rate Of Increase ◽

Urban Heat

The term “urban heat island” (UHI) describes increased surface and atmospheric temperatures in an urban core relative to surrounding non-urbanized areas. Although the phenomenon has been studied to a great extent throughout the world, it is less understood for Kathmandu, Nepal. This study used the Moderate Resolution Imaging Spectro-radiometer (MODIS) 8-day product (MOD11A2) to evaluate land surface temperatures (LSTs), the MODIS-derived Normalized Difference Vegetation Index (NDVI) 16-day product (MOD13Q1) to quantify land surface characteristics, and the MODIS annual land cover classification product (MCD12Q1) to identify major land cover classes. We evaluated the spatial correlation between significant changes in LSTs and NDVI between 2000–2018. Overall, urban (permanently developed areas) LSTs were consistently greater than non-urban (forests and dynamic agriculture lands) LSTs; however, the rate of increase in temperature was higher outside the central Kathmandu developed urban area. Furthermore, significant changes in NDVI values over time were more widespread and not always spatially coincident with significant changes in LST values, particularly for forested land areas. These results provide insight into systematic planning of open and green areas, construction of new infrastructure in peripheral areas, and highlight the challenges in applying traditional UHI conceptual models to rapidly developing urban areas such as Kathmandu, Nepal.

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Analysis of the diurnal cycle of air temperature between rural Berkshire and the University of Reading: possible role of the urban heat island

Weather ◽

10.1002/wea.3807 ◽

2020 ◽

Vol 75 (8) ◽

pp. 235-241

Author(s):

Aaron Nicholson

Keyword(s):

Urban Heat Island ◽

Air Temperature ◽

Diurnal Cycle ◽

Heat Island ◽

Urban Heat ◽

The University

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Contribution of urban park to thermal comfort and CO2 mitigation in a hot-humid environment

10.5194/egusphere-egu2020-21074 ◽

2020 ◽

Author(s):

Keunmin Lee ◽

Je-Woo Hong ◽

Jeongwon Kim ◽

Jinkyu Hong

Keyword(s):

Urban Heat Island ◽

Urban Areas ◽

Surface Air Temperature ◽

Urban Parks ◽

Economic Benefits ◽

Urban Park ◽

Heat Island ◽

Wide Range ◽

Urban Heat

Urban parks provide a wide range of services for healthcare and social welfare. In particular, they function as a key link connected to urban ecosystems, mitigating various environmental problems such as urban heat island effect and greenhouse emission. It is, therefore, urgent to improve our understanding of the role of the urban park in regulating their surrounding environment. We observed surface turbulent fluxes at an artificially constructed Seoul Forest Park (SFP) in Seoul, for two years from June 2013 to May 2015. The objectives of the study are to 1) quantify water, energy and CO2 exchanges from urban park into the atmosphere and 2) quantify the effect of the urban park on microclimate through comparison before and after the park construction and comparison with urbanized surrounding areas and 3) identify abiotic and biotic factors controlling the temperature reduction and CO2 offset.Our analysis shows that SFP in summer daytime has cooler surface air temperature up to -0.6 &#8451; with a Bowen ratio of 0.15 than surrounding commercial-residential zone in Seoul. SFP also acts as local sinks, and its carbon uptake gives economic benefits in terms of a carbon tax and reduction of heatwaves. Our findings indicate the important role of urban parks in mitigating urban heat island intensity and CO2 emission from urban areas and in providing eco-social benefits with us.

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