The sensitivity of urban heat island to urban green space-A model-based study of City of Colombo, Sri Lanka

Maheng, M.D.; Ducton, Ishara; Lauwaet, Dirk; Zevenbergen, C.; Pathirana, Assela

doi:10.3390/atmos10030151

The sensitivity of urban heat island to urban green space-A model-based study of City of Colombo, Sri Lanka

Title

The sensitivity of urban heat island to urban green space-A model-based study of City of Colombo, Sri Lanka

Author

Maheng, M.D. (TU Delft Hydraulic Structures and Flood Risk; IHE Delft Institute for Water Education; Universitas Muhammadiyah Kendari)
Ducton, Ishara (IHE Delft Institute for Water Education)
Lauwaet, Dirk (Flemish Institute for Technological Research)
Zevenbergen, C. (TU Delft Hydraulic Structures and Flood Risk; IHE Delft Institute for Water Education)
Pathirana, Assela (IHE Delft Institute for Water Education)

Date

2019

Abstract

Urbanization continues to trigger massive land-use land-cover change that transforms natural green environments to impermeable paved surfaces. Fast-growing cities in Asia experience increased urban temperature indicating the development of urban heat islands (UHIs) because of decreased urban green space, particularly in recent decades. This paper investigates the existence of UHIs and the impact of green areas to mitigate the impacts of UHIs in Colombo, Sri Lanka, using UrbClim, a boundary climate model that runs two classes of simulations, namely urbanization impact simulations, and greening simulations. The urbanization impact simulation results show that UHIs spread spatially with the reduction of vegetation cover, and increases the average UHI intensity. The greening simulations show that increasing green space up to 30% in urban areas can decrease the average air temperature by 0.1 °C. On the other hand, converting entire green areas into urban areas in suburban areas increases the average temperature from 27.75 °C to 27.78 °C in Colombo. This demonstrates the sensitivity of UHI to vegetation cover in both urban and suburban areas. These seemingly small changes are average grid values and may indicate much higher impacts at sub-grid levels.

Subject

Green space
Urban heat island
UrbClim

To reference this document use:

http://resolver.tudelft.nl/uuid:aca5cd45-4363-44a3-b9d3-3563ee3a0806

DOI

https://doi.org/10.3390/atmos10030151

ISSN

2073-4433

Source

Atmosphere, 10 (3)

Part of collection

Institutional Repository