Evaluation of Urban Heat Island (UHI) Spatial Change in Freshwater Lakes with Hot Spot Analysis (GI Statistics)

  • M. D. K. L. Gunathilaka University of Colombo
  • W. T. S. Harshana Urban Development Authority
Keywords: Hot and Cold Spots, Land Surface Temperature, Normalized Difference Vegetation Index, Remote Sensing, Surface Temperature

Abstract

Monitoring spatial changes of surface heat island formation and temperature changes in sub-urban areas is vital in the freshwater lake management of urban areas as frequent phenomena related to climate change have undergone. The purpose of this study was to examine the Spatio-temporal pattern of urban heat island and land surface temperature and vegetation changes by using GI statistics, where hotspot analysis was also performed. The study further examined the effect of heat island and surface temperature on urban freshwater lakes where hot and cold spots identified had undergone a reclassification process. The results revealed that the increasing Land Surface Temperature (LST) due to modification and transformation of vegetated areas into concrete and synthetic built-up extents is one of the challenging problems in the selected suburbs. Both NDVI and LST hot spots and cold spots have changed compared to 2010. The LST showed considerable expansion of the hotspots within ten years rather than cold spots in all three suburbs. The freshwater lakes are in proximity to the city. All three lakes were finally reclassified as hotspot areas for LST, while Kesbewa Lake and Thalangama Lake were identified as NDVI hotspots where the vegetation cover had contracted by 2020. Even though Boralesgamuwa Lake is not recognized as an NDVI hotspot, the encroachment and expansion of the current hotspot area could be identified. The study's findings could be used to design sustainable cities in these suburbs more by prioritizing the conservation of urban ecosystems. 

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References

NASA, “Global Climate Change,” 2015. https://climate.nasa.gov/news/2378/study-climate-change-rapidly-warming-worlds-lakes/ (accessed Mar. 05, 2021).

S. L. Postel, “Entering an era of water scarcity: the challenges ahead,” Ecol. Appl., vol. 10, no. 4, pp. 941–948, 2000.

J. S. Wallace, “Increasing agricultural water use efficiency to meet future food production,” Agric. Ecosyst. Environ., vol. 82, no. 1–3, pp. 105–119, 2000.

S. Levis, “Modeling vegetation and land use in models of the Earth System,” Wiley Interdiscip. Rev. Clim. Chang., vol. 1, no. 6, pp. 840–856, 2010.

J. S. Risbey, “The new climate discourse: Alarmist or alarming?,” Glob. Environ. Chang., vol. 18, no. 1, pp. 26–37, 2008.

M. K. Van Aalst, “The impacts of climate change on the risk of natural disasters,” Disasters, vol. 30, no. 1, pp. 5–18, 2006.

M. Ranagalage, R. C. Estoque, X. Zhang, and Y. Murayama, “Spatial changes of urban heat island formation in the Colombo District, Sri Lanka: Implications for sustainability planning,” Sustainability, vol. 10, no. 5, p. 1367, 2018.

T. R. Oke, “The energetic basis of the urban heat island,” Q. J. R. Meteorol. Soc., vol. 108, no. 455, pp. 1–24, 1982.

R. U. Halwatura and N. M. Nishad, “Effects of greenery on city comfort in different micro climatic conditions,” 2012.

A. Mace, “Suburbanization,” Elsevier, 2009.

A. Kobayashi, International encyclopedia of human geography. Elsevier, 2019.

S. Guha, H. Govil, and M. Besoya, “An investigation on seasonal variability between LST and NDWI in an urban environment using Landsat satellite data,” Geomatics, Nat. Hazards Risk, vol. 11, no. 1, pp. 1319–1345, 2020.

S. Guha, H. Govil, A. Dey, and N. Gill, “Analytical study of land surface temperature with NDVI and NDBI using Landsat 8 OLI and TIRS data in Florence and Naples city, Italy,” Eur. J. Remote Sens., vol. 51, no. 1, pp. 667–678, 2018.

W. Yue, J. Xu, W. Tan, and L. Xu, “The relationship between land surface temperature and NDVI with remote sensing: application to Shanghai Landsat 7 ETM+ data,” Int. J. Remote Sens., vol. 28, no. 15, pp. 3205–3226, 2007.

E. Johansson and R. Emmanuel, “The influence of urban design on outdoor thermal comfort in the hot, humid city of Colombo, Sri Lanka,” Int. J. Biometeorol., vol. 51, no. 2, pp. 119–133, 2006.

F. Foussenia, H. H. Guoa, Z. X. Haia, J. L. Seburanga, S. A.-S. Mande, and A. Koffi, “Urban area vegetation changing assessment over the last 20 years based on NDVI,” Energy Procedia, vol. 11, pp. 2449–2454, 2011.

M. Gunathilaka, “Modelling the Behavior of DVI and IPVI Vegetation Indices Using Multi-Temporal Remotely Sensed Data,” Int. J. Environ. Eng. Educ., vol. 3, no. 1, pp. 9–16, 2021.

ESRI, “What is a z score? What is a p-Value?,” 2016. http://pro.arcgis.com/en/pro-app/tool-reference/spatial-statistics/what-is-a-z-score-what-is-a-p-value.htm (accessed Feb. 20, 2021).

UN. Population Division, World urbanization prospects : the 2018 revision, Population. New York: United Nations Publications, 2018.

M. Jordan et al., The earth as transformed by human action: global and regional changes in the biosphere over the past 300 years. CUP Archive, 1990.

B. Moss, Ecology of fresh waters: a view for the twenty-first century. John Wiley & Sons, 2010.

J. D. Allan, “Landscapes and riverscapes: the influence of land use on stream ecosystems,” Annu. Rev. Ecol. Evol. Syst., vol. 35, pp. 257–284, 2004.

Published
2021-08-12
How to Cite
[1]
M. D. K. L. Gunathilaka and W. T. S. Harshana, “Evaluation of Urban Heat Island (UHI) Spatial Change in Freshwater Lakes with Hot Spot Analysis (GI Statistics)”, Int. J. Environ. Eng. Educ., vol. 3, no. 2, pp. 48-58, Aug. 2021.
Section
Research Article