URBAN HEAT ISLAND

12th EMS Annual Meeting & 9th European Conference on Applied Climatology (ECAC), 2012, Poland

2012-06-06T19:25:00.000+08:00

Simulation of Urban Heat Island Effects on the Microclimate: Using ENVI-met Model

Parisa Shahmohamadi, Ulrich Cubasch, Sahar Sodoudi

Institut für Meteorologie, Freie Universität Berlin, Germany

Abstract

This paper used the tree-dimensional microclimate model ENVI-met 4.0 which prognosticates the microclimate changes within urban environments to simulate the UHI intensity in 6 urban district of Tehran metropolitan area. The variables used in this study are higher albedo materials and vegetation cover. Three different scenarios have been defined including: 1. covering horizontal and vertical surfaces with higher albedo materials; 2. covering vertical and horizontal surfaces with vegetation covers and 3. covering vertical and horizontal surfaces with vegetation covers and high albedo material altogether. To observe the effect of each single and both variables on mitigating urban heat island in an urban area. The simulations, which run in a hot summer day for 24 hours, are compared and the results are discussed.

Key Words: ENVI-met, High Albedo Material, Vegetation Cover, Urban Heat Island.

Eighth International Conference on Urban Climate 2012, Dublin, Ireland

2012-04-27T20:01:00.001+08:00

The Simulation of “Natural Ventilator of the City” Model by Using ENVI-met to Mitigate the Effect of Urban Heat Island in Tehran Metropolitan Area

Parisa Shahmohamadi¹, Ulrich Cubasch¹, Sahar Sodoudi¹, A.I. Che-Ani²

¹Institut für Meteorologie, Freie Universität Berlin, Germany

² Department of Architecture, Faculty of Engineering and Built Environment,

Universiti Kebangsaan Malaysia, Selangor, Malaysia

Abstract

Natural Ventilator of the City (NVC) model has been recommended by this paper to mitigate the UHI intensity in Tehran metropolitan area. The main aim of this model is to achieve ideal condition with zero effects of UHI. In order to achieve this condition, hypothesis has been considered which if the half of 6 urban district of Tehran covers with vegetation covers and high albedo materials, it could be approached to this condition. 6 urban district, as a central district of Tehran, is one of the polluted areas which plays an important role on formation of UHI. Providing different kinds of greenery such as balcony gardens, green roofs and vertical and horizontal landscape in barren and urban lands along with using higher albedo materials can convert 6 urban district into the central ventilator. In this way, providing this natural ventilator in 6 urban district can affect the surrounding areas and mitigate the UHI intensity in whole part of the metropolitan area. Therefore, in order to prove whether the ideal condition is achievable or not, simulation of NVC model by using the micro scale climate model ENVI-met has been done. The result will be presented and discussed.

Key Words: ENVI-met, Natural Ventilator of the City Model, Urban Heat Island.

UEP 2012 Conference (Creating Healthy, Liveable Cities)- Amsterdam, Netherlands

2012-03-15T18:11:00.003+08:00

Natural Ventilator of the City: a Model for Alleviating Urban Heat Island

Parisa Shahmohamadi¹, Ulrich Cubasch¹, Sahar Sodoudi¹, A.I. Che-Ani²

¹Institut für Meteorologie, Freie Universität Berlin, Germany

² Department of Architecture, Faculty of Engineering and Built Environment,

Universiti Kebangsaan Malaysia, Selangor, Malaysia

Abstract

The present paper deals with the dependence of alleviating urban heat island (UHI) on the design of an appropriate model. The model called “Natural Ventilator of the City”, recommended by this paper, has two different components including: 1) meteorological and urban structure factors which with their interactions form UHI over the urban areas; 2) vegetation covers and high albedo materials which contribute to mitigate the produced UHI. Compiling the key components into model is meaningful in promoting the passive climate control brought by vegetation covers and high albedo materials in an urban area. The interactions among the key components and the way of contribution of variables to alleviate the UHI effects are presented in the model. This study has chosen a district of Tehran as a case study. In order to test the model three approaches are presented, showing the results of UHI measurement using satellite image, UHI modeling using spatial analyses based on ArcGIS and urban climate simulations using three dimensional microclimate model ENVI-met which prognosticates the microclimate changes within urban environments.

Key Words: ENVI-met, High Albedo Material, “Natural Ventilator of the City” Model, Vegetation Cover, Urban Heat Island.

Sciencedirect

2012-01-20T19:21:00.011+08:00

Healthy Environment: The Need to Mitigate Urban Heat Island Effects on Human Health

P. Shahmohamadi1¹, A.I. Che-Ani1¹, I. Etessam², K.N.A. Maulud³, N.M. Tawil¹

¹Department of Architecture, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

²Department of Architecture and Urban Design, Faculty of Fine Art, Tehran University, Iran

³Department of Civil and Structural Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

Abstract

This paper is focused on understanding the most important factors of UHI formation and their effects on urban population health with an emphasis on the considerable growth of both population and rapid urbanization of Tehran, Iran. To achieve this aim, this paper explores literally a conceptual framework about the relationship between UHI and human health. Then, it suggests three important strategies to minimise the impact of UHI on human health: achieving appropriate transportation for mitigating air pollution, providing appropriate landscape, increasing the albedo of building materials.

Keywords: Albedo Materials; Healthy Environment; Horizontal Landscape; Human Health; Vertical Landscape; Urban Heat Island

See web site: http://www.sciencedirect.com/science/article/pii/S1877705811029481

WSEAS TRANSACTIONS on ENVIRONMENT and DEVELOPMENT

2011-04-14T03:35:00.000+08:00

The Link between Urbanization and Climatic Factors: A Concept on Formation of Urban Heat Island

P. SHAHMOHAMADI, A.I. CHE-ANI, N.A.G. ABDULLAH,
M.M. TAHIR, K.N.A. MAULUD, M.F.I. MOHD-NOR
Faculty of Engineering and Built Environment, UKM

Increasing the number of population, pollutions, urban expansion and many other kinds of urbanization factors in metropolitan areas are affected climatic factors and vice versa. In fact, there is a correlation between these two factors in general. This paper put forward the conceptual model and two hypotheses. In order to test the model, UHI mapping has been carried out in Tehran as a case study. The investigation has been done at macro-level to get surface temperature. The methodology employed is to use satellite image with a thermal band (obtained on 18 July 2000). To map out the UHI, mapping of LST and NDVI were necessary and then overlaid them and extracted maximum temperature value for both urban and rural areas. The results show that the maximum urban and rural temperature values are 39°C and 27°C respectively. Therefore, daytime Tehran surface UHI shows 12ºC of difference between urban and rural areas which is quite strong. Analyzing the data specified that the urbanization factors have direct impact on increasing the UHI intensity in Tehran metropolitan area.

Key-Words: - Climatic Factors, Environmental Challenge, Tehran, Urban, Urban Heat Island, Urbanization Factors

The 2nd International Building Control Conference

2011-02-05T14:28:00.001+08:00

Healthy Environment: The Need to Mitigate Urban Heat Island Effects on Human Health

P. Shahmohamadi1¹, A.I. Che-Ani1¹, I. Etessam², K.N.A. Maulud³, N.M. Tawil¹

¹Department of Architecture, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

²Department of Architecture and Urban Design, Faculty of Fine Art, Tehran University, Iran

³Department of Civil and Structural Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

Abstract

Climate changes such as changes in temperature and precipitation, sea level, fisheries, agriculture, natural ecosystems, and air quality will all directly or indirectly affect human morbidity (illness) or mortality. One of the great challenges facing our current generation of scientists and engineers is how to protect urban population from health stress associated with summertime heat. As heat-waves are likely to increase in frequency because of global climate change, the most effective interventions, measures and policies to protect the health need to be developed and evaluated. Therefore, this paper is focused on understanding the most important factors of UHI formation and their effects on urban population health with an emphasis on the considerable growth of both population and rapid urbanization of Tehran, Iran. To achieve this aim, this paper explores literally a conceptual framework about the relationship between UHI and human health. Then, it suggests three important strategies to minimize the impact of UHI on human health: achieving appropriate transportation for mitigating air pollution, providing appropriate landscape, and increasing the albedo of building materials.

Keywords: building material, healthy environment, human health, urban heat island, urban landscape

2011-02-01T18:51:00.002+08:00

Achieving Energy Consumption Balance in Kuala Lumpur Shophouses by Mitigating Urban Heat Island Effects: Focusing on Anthropogenic Heat Factor

P. Shahmohamadi, A.I. Che-Ani, K.N.A. Maulud, N.M. Tawil, N.A.G. Abdullah

Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

shahmohamady@hotmail.com, adiirfan@gmail.com

ABSTRACT

Production of anthropogenic heat and using energy for cooling systems, lighting and etc. led to have serious impacts on the thermal environmental quality such as quality of the air, increase in temperature, energy consumption and finally the formation of UHI. Shophouses represent important land uses in Kuala Lumpur since many years ago, which influence the resulting thermal environment including the formation of urban heat island (UHI). This paper investigates the impact of anthropogenic heat on formation of urban heat island and increasing energy consumption. It explores literally the conceptual framework of confliction between anthropogenic heat and urban structure, which produce UHI intensity and affected energy consumption balance. It is then discussed how these two factors can be affected and gives implication to the city and then, focuses on whether actions should be taken for balancing adaptation and mitigation UHI effects. It will be concluded by making the important strategies to minimize the impact of UHI on energy consumption.

Key Words: Energy Consumption Balance, Kuala Lumpur, Shophouses, Urban Heat Island.

Journal of Environmental Technology and Engineering

2010-12-27T13:02:00.006+08:00

Interaction between Urbanization and Climatic Factors on Formation of Urban Heat Island as an Environmental Challenge: the Conceptual Framework of Tehran Metropolitan Area, Iran

Parisa Shahmohamadi¹

¹ Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Malaysia

Email: shahmohamady@hotmail.com

A..I. Che-Ani¹,Iraj Etessam², K.N.A. Maulud¹, M.F.I. Mohd-Nor¹

² Faculty of Fine Art, Tehran University, Iran

Tehran has experienced rapid growth of urbanization and industrialization since it became the capital (200 years ago) and this has caused serious environmental problems in the city. In an urban area, one of the great problems is urban heat island (UHI) effect, which is due to many factors such as urbanization and climatic factors, resulting from the production and accumulation of heat in the urban mass. The main characteristics of UHI effect are the raised temperatures in the city centre, leading to excessive energy use for cooling and putting urban population at great morbidity and mortality risks. Therefore, it becomes increasingly important to study that how could various factors form UHI over the city in order to reduce environmental challenges. This paper, therefore, is focused on urbanization and climatic factors to understand the influence way of these factors on formation of UHI. In addition, it is showed this formation is related to the interaction between the urbanization and climatic factors. Thus, the percentage of UHI formation is high when great interaction exists. To achieve this aim, with the case study of city of Tehran, this paper explores literally the conceptual framework of interaction between urbanization and climatic factors on formation of UHI. It is then discussed how these two different kinds of factors can be affected and give implication to the city, and then, focuses on whether actions should be taken for balancing adaptation and mitigation UHI effects in Tehran metropolitan area. It will then conclude by making the recommendations for preventive action in provide quality of life.

Index Terms— Climatic Factors, Environmental Challenge, Urban Heat Island, Urbanization Factors.

International Journal of Sustainable Development and Planning

2010-12-24T18:01:00.006+08:00

The Conceptual Framework on Formation of Urban Heat Island in Tehran Metropolitan, Iran: A Focus on Urbanization Factor

P. SHAHMOHAMADI, A.I. CHE-ANI, N.A.G. ABDULLAH, K.N.A. MAULUD, M.M. TAHIR, M.F.I. MOHD-NOR

In an urban area, one of the great problems is urban heat island effect, which is due to many factors such as urbanization and climatic factors, resulting from the production and accumulation of heat in the urban mass. The main characteristics of UHI effect are the raised temperatures in the city centre, leading to excessive energy use for cooling and putting urban population at great morbidity and mortality risks. Therefore, it becomes increasingly important to study that how could various factors form UHI over the city in order to reduce environmental challenges. This paper, therefore, is focused on urbanization and climatic factors to understand the influence way of these factors on formation of UHI. The percentage of UHI formation is high when great interaction exists. This paper explores literally the conceptual framework of interaction between urbanization and climatic factors on formation of UHI with the case study of city of Tehran. The urbanization factors that affect Tehran are discussed in relation to location of the city, the size of the city and population, density of built-up area, urban geometry, thermal property of fabric, surface waterproofing, anthropogenic heat, air pollution, land use and wind speed.

Key-Words: Climatic Factors, Environmental Challenge, Tehran, Urban, Urban Heat Island,
Urbanization Factors

see this site: http://journals.witpress.com/journals.asp?iID=54#papers

Journal of Civil Engineering and Architecture, USA

2010-12-01T11:54:00.010+08:00

Conflict between Population and Urbanization Factors: Impact of Urban Heat Island on Energy Consumption Balance

Parisa Shahmohamadi, Che-Ani A.I., Iraj Etessam, Khairul Nizam Abdul Maulud, M.F.I. Mohd-Nor

High density of buildings and population in urban areas increases urban temperature, generally known as the urban heat island. Raised temperature, especially in summer, turns city centers into unwelcome hot areas, with direct effects on electricity demand and energy consumption for cooling buildings and increases the production of carbon dioxide and other pollutants. Therefore, by considering that the energy consumption in the world has been faced with intense crisis, it becomes increasingly important to study the effects of urban heat island on energy consumption in order to improve people’s environment and decrease energy use in cities. This paper, therefore, is focused on urbanization and population size factors to understand the influence way of these factors on formation of UHI and energy consumption balance. To achieve this aim, this paper explores literally the conceptual framework of conflict ion between population and urban structure, which produce UHI intensity and affected energy consumption balance. It is then discussed how these two factors can be affected and give implication to the city, and then, focuses on whether actions should be taken for balancing adaptation and mitigation UHI effects. It will be concluded by making the recommendations for preventive action and provide quality of life.

Keywords: Energy Consumption Balance, Urban Construction, Urban Heat island, Urban Population

UKM Journal

2010-11-05T13:36:00.002+08:00

Integration of Characteristics of Urban Construction Materials: The Way for Mitigation of Urban Heat Island

P.Shahmohamadi, A.I. Che-Ani and M. F.I. Mohd-Nor

Urban heat island effect is due to many factors such as inappropriate urban construction materials, resulting from the production and accumulation of heat, increasing of energy consumption and pollution in the urban mass. Different characteristics of materials, albedo, emissivity and porosity, can impact on formation of UHI. Using low albedo, emissivity and porosity materials in urban areas can extremely increase the effect of UHI. It means the quality of materials is in indirect ratio to UHI which by increasing the quality of materials, the effects of UHI is decreased and vice versa. To achieve this aim, this paper literally explores the conceptual framework to show the correlation between UHI and urban construction materials and discuses about the integration of characteristics of construction materials which can mitigate UHI effects.

Keywords: Albedo, Emissivity, Porosity, Urban Construction Material, Urban Heat Island.

European Journal of Scientific Research

2010-10-23T09:48:00.004+08:00

Mitigating the Urban Heat Island Effect: Some Points without Altering Existing City Planning

A.I. Che-Ani, P. Shahmohamadi, A. Sairi, M.F.I. MOH-NOR

Urban Heat Island is expected to pose increasing challenges for cities in the following decades, placing greater stress and impacts on multiple social and biophysical systems, including population health, social comfort, urban infrastructure, energy demand and water supplies. One of the great challenges facing our current generation of scientists and engineers is how to mitigate the harmful effects of urban heat island and make the sustainable cities. In the first step, the root cause of problems and the effects of urban heat island must be recognized. And then by considering the effects of UHI on all aspects of urban environment is started thinking about the mitigation of UHI. This paper therefore, is focused on understanding the main roots of UHI problems on urban environment with an emphasis on the recognition of the effects of UHI. To achieve this aim, this article review current knowledge about the urban heat island to understand urban climate, urban climate scales and the harmful effects of UHI, including human health, patterns of human settlement, energy use, transportation, industry, environmental quality, and other aspects of infrastructure that effect our quality of life, and then classify these effects, make some recommendations for preventive action and provide quality of life and sustainability in city.

Keywords: Livable city, Quality of Life, Urban Heat Island.

see this site: http://www.eurojournals.com/ejsr.htm

ISI/SCOPUS Indexed Journal Paper

2010-10-21T00:43:00.003+08:00

Reducing urban heat island effects: A systematic review to achieve energy consumption balance

P.Shahmohamadi, A.I. Che-Ani, A. Ramly, K.N.A. Maulud and M. F.I. Mohd-Nor

Considering the current energy consumption worldwide, it has become increasingly important to study the effects of urban heat island on energy consumption in order to improve the environment. This paper investigates the impact of Urban Heat Island (UHI) on energy consumption and also determines which factors can directly affect energy use in the city. The UHI current knowledge and literature are reviewed, as well as how UHI can affect energy consumption. This paper explores literally the conceptual framework of confliction between population and urban structure, which produce UHI intensity and affected energy consumption balance. It is then discussed how these two factors can be affected and gives implication to the city and then, focuses on whether actions should be taken for balancing adaptation and mitigation UHI effects. It will be concluded by making the three important strategies to minimise the impact of UHI on energy consumption: providing an appropriate landscape, using appropriate materials on external surfaces of buildings and urban areas and promoting natural ventilation.

Key Words: Energy consumption, quality of life, urban heat island, urban temperature.

See this site: http://www.academicjournals.org/ijps/contents/2010cont/Jun.htm

Urban Heat Island Books

2010-10-20T13:02:00.002+08:00

Urban heat islands are metropolitan areas that are significantly warmer than their surroundings. The main causes are modification of the land surface by urban development and waste heat generated by energy usage. Heat island problems are becoming more pressing as cities continue to grow and sprawl. This comprehensive book brings together the latest information about heat islands and their mitigation. Heat island formation and the problems they cause, mitigation technologies and their benefits and policies, and actions for cooling communities are described in full. The author includes sections on roof cooling and cool paving and explains their benefits in detail, providing practical guidelines for their selection and installation. The book also includes effective methodologies for using trees and vegetation for cooling, such as green roofs. In this groundbreaking book, Lisa Gartland offers a comprehensive source of information for turning heat islands into cool communities.

Conventional air conditioning is not a sustainable solution to the challenge of a hot or humid climate. The climate problem is compounded in so-called Urban Heat Islands, urban areas where the air can be 3-5°C hotter than its surrounding areas and where pollution levels are consequently raised. Including a colour section with thermal images and maps, this book explores the complex relationships between climate, buildings and plants, especially in urban heat islands. These relationships bear very critically on a range of environmental issues and point to some corresponding solutions. One chapter highlights some of the extensive research work carried out in Singapore, especially investigating the thermal benefits of greenery in buildings in the urban setting. Though several books have been written on urban heat islands, this work uniquely examines the linkages between climate, buildings and plants. It forms a reference for researchers and professionals such as architects, architectural science, landscape architects, building services engineers, urban planners and urban climatologists. It may also be useful for final year undergraduates or graduate students in these disciplines.

Urban Heat Island Groups

2010-10-20T00:19:00.000+08:00

http://www.epa.gov/heatisld/

http://www.urban-climate.org/

http://heatisland.lbl.gov/

Journal Publications

2010-10-19T11:37:00.003+08:00

First of all, it is better to have general idea about my publications and background. So, i just put the list of Journal publications as below:

1. P. Shahmohamadi, A.I. Che-Ani, N.A.G. Abdullah, K.N.A. Maulud, M.M. Tahir and M.F.I. MOHD-NOR (2010). "The Correlation between Urbanization and Climatic Factors: a Concept on Formation of Tehran Urban Heat Island". International Journal of Energy and Environment, WSEAS Transactions on Environment and Development, Japan (submitted for publication).

2. P. Shahmohamadi, A.I. Che-Ani, A. Ramly, K.N.A. Maulud, M.F.I. Mohd-Nor (2010). “Reducing Urban Heat Island Effects: A Systematic Review to Achieve Energy Consumption Balance”. International Journal of Physical Sciences. 5(6) Jun. 2010:626-636. [ISSN 1992-1950] – ISI/SCOPUS Indexed.

3. P. Shahmohamadi, A.I. Che-Ani, K.N.A. Maulud, A. Sairi, M.F.I. Mohd-Nor (2010). “The Framework to Mitigate the Urban Heat Island Effect for Improving Environment and Protecting Human Health”. International Journal of Sustainable Development and Planning. 5(1). [ISSN 1743-7601 EISSN 1743-761X] – SCOPUS Indexed.

4. P. Shahmohamadi, A.I. Che-Ani, I. Etessam, K.N.A. Maulud, M.F.I. Mohd-Nor (2010). “Interaction between Urbanization and Climatic Factors on Formation of Urban Heat Island as an Environmental Challenge: The Conceptual Framework of Tehran Metropolitan, Iran”. Journal of Environmental Technology and Engineering [ISSN 2072-1463].

5. P. Shahmohamadi, A.I. Che-Ani, I. Etessam, K.N.A. Maulud, M.F.I. Mohd-Nor (2010). “Conflict between Population and Urbanization Factors: Impact of Urban Heat Island on Energy Consumption Balance”. Journal of Civil Engineering and Architecture [ISSN 1934-7359]. (full paper submitted on 28 August 2010) – Non-ISI/Non-SCOPUS.

6. P. Shahmohamadi, A.I. Che-Ani, M.F.I. Mohd-Nor, N.M. Tawil, N.A.G. Abdullah (2010). “Integration of Characteristics for Urban Construction Materials: The Way to Mitigate Urban Heat Island”. Buletin INNOVATE. FKAB UKM. Vol. 3/January 2010. pp.27-29.

7. A.I. Che-Ani, P. Shahmohamadi, A. Sairi, M.F.I. Mohd-Nor, M.F.M. Zain, M. Surat (2009). “Mitigating the Urban Heat Island Effect: Some Points Without Altering Existing City Planning”. European Journal of Scientific Research. 35(2) Aug. 09:204-216. [ISSN 1450-216X] – SCOPUS Indexed.

Introduction of Blogger

2010-10-19T00:36:00.001+08:00

Urban Heat Island is expected to pose increasing challenges for cities in the following decades, placing greater stress and impacts on multiple social and biophysical systems, including population health, social comfort, urban infrastructure, energy demand and water supplies. One of the great challenges facing our current generation of scientists and engineers is how to mitigate the harmful effects of urban heat island and make the sustainable cities. Negative impacts of UHI affect so many people in so many way. UHIs do not just cause a bit of additional, minor discomfort. Their higher temperatures, lack of shade and role in increasing air pollution have serious effects on human mortality and disease. They waste money by increasing the need for energy consumption, for building and infrastructure maintenance, for the management of storm water run-off and for the disposal of waste. In addition, the barren construction techniques that foster UHIs tend to be unattractive, unappealing and unhealthy for urban flora and fauna.Therefore, the benefits of mitigation of UHIs are very large.

The major aim of this blog is to introduce the negative impacts of UHIs for those who do not know about this huge matter and its effects on urban areas. So, this hopefully might be one step forward solving this matter and inform people about the depth of disaster.

I would really appreciate it if anybody knows any new information about UHI please let us know about that.

Thanks all

Parisa