Urban heat hazard on University of Malaya Campus

As education area, campus or university is full with various activities which have an impact on the existence of land-use or land-cover. The variation of activities dynamically change the shape of land-use or land-cover within the campus area, thus also create variations in Land Surface Temperature (LST). The LST are impacting the coziness of human activity especially when reaches more than 30 oC. This study used the term Urban Heat Signature (UHS) to explain LST in different land-use or land-cover types. The objective of this study is to examine UHS as an Urban Heat Hazard (UHH) based on Universal Temperature Climate Index (UTCI) and Effective Temperature Index (ETI) in University of Indonesia. Thermal bands of Landsat 8 images (the acquisition year 2013-2015) were used to create LST model. A ground data known as Air Surface Temperature (AST) were used to validate the model. The result showed an increased level of maximum temperature during September-October since 2013 until 2014. The maximum temperature was reduced in October 2014, however it increased again in August 2015. The UTCI showed “moderate” and “strong heat stress”, while EFI showed “uncomfortable” and “very uncomfortable” categories during that period. This research concluded that build up area in UI Campus highest temperature on UI campus based on UHS. Range UHS in Campus UI on 2013 (21.8-31.1oC), 2014 (25.0-36.2oC) and 2015 (24.9-38.2oC). This maximum UHS on September (2014 and 2015) put on levelling UTCI included range temperature 32-35oC, with an explanation of sensation temperature is warm and sensation of comfort is Uncomfortable, Psychology with Increasing Stress Case by Sweating and Blood Flow and Health category is Cardiovascular Embarrassment. This UHS occurs in September will give impact on psychology and health, that’s become the UHH of the living on education area.

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A mobile sensor-based Approach for Analyzing and Mitigating Urban Heat Hazards

10.5194/egusphere-egu2020-12446 ◽

2020 ◽

Author(s):

Yanzhe Yin ◽

Andrew Grundstein ◽

Deepak Mishra ◽

Navid Hashemi ◽

Lakshmish Lakshmish

Keyword(s):

Machine Learning ◽

Air Temperature ◽

Heat Exposure ◽

Ambient Air ◽

Temperature Data ◽

Mobile Sensors ◽

Mobile Sensor ◽

High Quality ◽

Urban Heat ◽

Heat Hazard

High-quality temperature data at a finer spatial-temporal scale is critical for analyzing the risk of heat hazards in urban environments. The variability of urban landscapes makes cities a challenging landscape for quantifying heat exposure. Most of the existing heat hazard studies have inherent limitations on two fronts: the spatial-temporal granularities are too coarse and the ability to track the actual ambient air temperature instead of land surface temperature. Overcoming these limitations requires radically different research approaches, both the paradigms for collecting the temperature data and developing models for high-resolution heat mapping. We present a comprehensive approach for studying urban heat hazards by harnessing a high-quality hyperlocal temperature dataset from a network of mobile sensors and using it to refine the satellite-based temperature products. We mounted vehicle-borne mobile sensors on thirty city buses to collect high-frequency (5 sec) temperature data from June 2018 to Nov 2019. The vehicle-borne data clearly show significant temperature differences across the city, with the largest differences of up to 10&#8451; and morning-afternoon diurnal changes at a magnitude around 20&#8451;. Then we developed a machine learning approach to derive a hyperlocal ambient air temperature (AAT) product by combining the mobile-sensor temperature data, satellite LST data, and other influential biophysical parameters to map the variability of heat hazard over areas not covered by the buses. The machine learning model output highlighted the high spatio-temporal granularity in AAT within an urban heat island. The seasonal AAT maps derived from the model show a well-defined hyperlocal variability of heat hazards which are not evident from other research approaches. The findings from this study will be beneficial for understanding the heat exposure vulnerabilities for individual communities. It may also create a pathway for policymakers to devise targeted hazard mitigation efforts such as increasing green space and developing better heat-safety policies for workers.

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An urban climate service to manage heat risks in UK and Chinese cities

10.5194/egusphere-egu21-5158 ◽

2021 ◽

Author(s):

Victoria Ramsey ◽

Claire Scannell

Keyword(s):

Urban Climate ◽

Evidence Base ◽

Extreme Heat ◽

Climate Services ◽

Extreme Heat Events ◽

Climate Service ◽

Urban Heat ◽

The Uk ◽

Heat Hazard ◽

The City

Recent extreme heat events in the UK are likely to become more frequent over the 21st Century and exacerbated in cities due to the urban heat island effect. Due to high population densities and a concentration of assets, urban areas are more vulnerable to climatic extremes with impacts that traverse health, infrastructure, built environment and economic activity. Risks to health, well-being and productivity from high temperatures is one of six priority areas from in UK Climate Change Risk Assessment (2017) where more action is needed to manage risks, prompting local authorities to understand heat risks within their city.&#160; City based climate services are needed for day-to-day operations in cities, emergency response and to inform urban design and development. &#160;Recent advances in high resolution modelling enable better representation of urban processes and provide greater understanding of extreme events. &#160;By exploiting such advances in underpinning science, the Met Office is generating urban climate services for city stakeholders to plan for and manage heat stress in their city. The Met Office has been engaging with local authorities and city stakeholders in the UK and China to co-produce a prototype, two tier, urban heat climate service to enhance the resilience of urban environments to extreme heat events. &#160;The prototype is based on a strong requirement from several cities to develop an evidence base of the heat hazard and understand current and future hot spots vulnerable to extremes of heat within the city. &#160;Tier 1 uses observations and high-resolution climate data to provide city specific information of the heat hazard in a graphical factsheet format. &#160;This includes information on future changes in temperature, extreme heat indicators, frequency and duration of heatwave events, and spatial distribution of heat across the city. &#160;Tier 2 involves working closely with city stakeholders to combine the hazard information with data on health, built environment and socio-economics, to provide tailored information on heat exposure and vulnerability. &#160;This will allow users to identify highly vulnerable parts of the city network and neighbourhoods for priority action. &#160;This two-tier service can provide an evidence base to inform urban policy, design and adaptation strategies, and prepare authorities and city stakeholders for future demand on city services.&#160;

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URBAN HEAT HAZARD THREAT ON UNIVERSITY CAMPUS

International Journal of Geomate ◽

10.21660/2020.76.95107 ◽

2020 ◽

Vol 19 (76) ◽

Author(s):

Adi Wibowo

Keyword(s):

University Campus ◽

Urban Heat ◽

Heat Hazard

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Orographic effects on calculation of the urban heat island intensity

Оптика атмосферы и океана ◽

10.15372/aoo20180208 ◽

2018 ◽

Keyword(s):

Urban Heat Island ◽

Urban Heat Island Intensity ◽

Heat Island ◽

Orographic Effects ◽

Urban Heat

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Analisis Pengaruh Kerapatan Vegetasi Terhadap Suhu Permukaan dan Keterkaitannya Dengan Fenomena UHI

Media Komunikasi Geografi ◽

10.23887/mkg.v21i1.24429 ◽

2020 ◽

Vol 21 (1) ◽

pp. 99

Author(s):

Dewi Miska Indrawati ◽

Suharyadi Suharyadi ◽

Prima Widayani

Keyword(s):

Urban Heat Island ◽

Landsat 8 ◽

Heat Island ◽

Landsat 8 Oli ◽

Urban Heat ◽

Split Window Algorithm

Kota Mataram adalahpusat dan ibukota dari provinsi Nusa Tenggara Barat yang tentunya menjadi pusat semua aktivitas masyarakat disekitar daerah tersebut sehingga menyebabkan peningkatan urbanisasi. Semakin meningkatnya peningkatan urbanisasi yan terjadi di perkotaan akan menyebabkan perubahan penutup lahan, dari awalnya daerah bervegetasi berubah menjadi lahan terbangun. Oleh karena itu, akan memicu peningkatan suhu dan menyebabkan adanya fenomena UHI dikota Mataram.Tujuan dari penelitian ini untuk mengetahui hubungan kerapatan vegetasi dengan kondisi suhu permukaan yang ada diwilayah penelitian dan memetakan fenomena UHI di Kota Mataram. Citra Landsat 8 OLI tahun 2018 yang digunakan terlebih dahulu dikoreksi radiometrik dan geometrik. Metode untuk memperoleh data kerapatan vegetasi menggunakan transformasi NDVI, LST menggunakan metode Split Window Algorithm (SWA) dan identifikasi fenomena urban heat island. Hasil penelitian yang diperoleh menunjukkan kerapatan vegetasi mempunyai korelasi dengan nilai LST. Hasil korelasi dari analisis pearson yang didapatkan antara kerapatan vegetasi terhadap suhu permukaan menghasilkan nilai -0,744. Fenomena UHIterjadi di pusat Kota Mataram dapat dilihat dengan adanya nilai UHI yaitu 0-100C. Semakin besar nilai UHI, semakin tinggi perbedaan LSTnya.

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PERUBAHAN PENUTUP LAHAN DAN KERAPATAN VEGETASI TERHADAP URBAN HEAT ISLAND DI KOTA SURAKARTA

Seminar Nasional Geomatika ◽

10.24895/sng.2018.3-0.1022 ◽

2019 ◽

Vol 3 ◽

pp. 641

Author(s):

Nafisatul Baroroh ◽

Pangi Pangi

Keyword(s):

Urban Heat Island ◽

Heat Island ◽

Urban Heat

Secara fisik, perkembangan perkotaan dapat terlihat dari perubahan penduduknya yang semakin bertambah dan semakin padat. Menurut data Badan Pusat Statistik, jumlah penduduk Kota Surakarta tahun 2000 yaitu sebesar 490.214 jiwa dan meningkat ±23.957 jiwa di tahun 2016. Pertumbuhan penduduk dan pembangunan yang pesat akan menyebabkan perubahan penggunaan lahan demi menunjang aktifitas penduduk yang seringkali mengakibatkan benturan kepentingan sehingga mengakibatkan menurunnya kualitas lingkungan. Hal itu disebabkan oleh semakin terdesaknya alokasi lahan untuk vegetasi. Perubahan lahan vegetasi yang tergantikan oleh jalan, bangunan dan struktur lain akan lebih banyak menyerap panas matahari dan memantulkannya, sehingga menyebabkan suhu permukaan di kota naik. Akibatnya semakin banyak titik-titik panas yang terbentuk sehingga menyebabkan perubahan unsur-unsur cuaca dan iklim sebagai pemicu terjadinya Urban Heat Island (UHI). Sesuai dengan uraian tersebut, maka tujuan penelitian ini adalah untuk menganalisis perubahan penutup lahan dan kerapatan vegetasi terhadap Urban Heat Island di Kota Surakarta. Metode analisis yang digunakan yaitu analisis deskriptif dan pengolahan data spasial. Berdasarkan hasil dari analisis menunjukkan bahwa jenis penutup lahan yang mendominasi adalah permukiman dan lahan terbangun, serta kelas kerapatan vegetasi didominasi oleh vegetasi jarang. Kemudian untuk distribusi suhu permukaan di Kota Surakarta secara keseluruhan tahun 1994, 2000 dan 2017 nilainya berubah, dimana rentang suhunya berkisar antara 21 C – 24 C (terendah) sampai dengan 34 C – 37 C (tertinggi). Perubahan suhu yang terjadi inilah mengindikasikan terjadinya fenomena Urban Heat Island di Kota Surakarta. Berdasarkan hal tersebut, maka dapat disumpulkan bahwa terdapat perubahan jenis penutup lahan dan juga kelas kerapatan vegetasi yang terjadi terhadap Urban Heat Island di Kota Surakarta.

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