A Review of Green Roofs to Mitigate Urban Heat Island and Kathmandu Valley in Nepal
A Review of Green Roofs to Mitigate Urban Heat Island and Kathmandu Valley in Nepal
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尼泊尔缓解城市热岛和加德满都谷地绿色屋顶综述
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
Gyan Chhipi
中科院分区：
文献类型：
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作者：
B. Baniya;K. Techato;S. Ghimire;Gyan Chhipi
城市气温一直在上升，绿化和高建筑面积减少。总人口的一半以上居住在城市地区，因此城市环境非常脆弱。恢复城市森林是非常昂贵的，几乎是不可能的，因为他们已经使用了大量的土地用于发展目的。在此背景下，绿色屋顶技术迅速兴起。它具有多方面的环境、美学和社会效益。它吸收大气中的碳，缓解城市热量，降低地表温度，从而降低能源需求和成本。由于这几个环境效益，绿色屋顶可以在加德满都实践。加德满都是南亚发展最快的城市之一，面临着与城市热有关的几个灾难性的环境问题。本文综述了城市热岛、绿色屋顶技术以及利用遥感和GIS扩展模型研究城市绿化和温度的研究进展。利用2000-2016年8个气象站的MODIS NDVI、CRU气候和月气温资料。采用Mann Kendell检验统计量和Sen斜率分析了加德满都河谷的气温变化。利用2010年的土地利用/土地覆盖数据，对加德满都流域的相关文献进行了综述。空气表面温度以0.04°C yr-1的速率显著增加，最高温度趋势为0.06°C。加德满都谷地2000-2016年的年平均气温为18.06°C，最高气温为24.15°C。相反，2000年的年平均地表温度为15.84°C-39.17°C，2014年为16°C-33.98°C。与此同时，城区面积急剧增加，平均地表温度大于平均气温，归一化植被指数值较低，而归一化植被建成指数值较高。这些环境后果是造成加德满都谷地城市热岛的主要因素。因此，绿色屋顶可以成为一种有效的缓解环境问题和城市热岛的工具。然而，在加德满都山谷实施绿色屋顶需要进行详细的调查。
Urban temperature has been escalating less greenery and high built up areas. More than half of the total population is residing in urban area so that the urban environment is highly vulnerable. Restoration of urban forestry is very expensive and almost not possible as they have already used the massive land for development purpose. In this context, green roofs technology has rapidly emerged. It has multifaceted environment, aesthetic and social benefits. It absorbs atmospheric carbon, mitigate urban heat and cool the surface temperature which reduces the energy demand and cost. Because of these several environmental benefits, green roofs can be practiced in Kathmandu. The Kathmandu, one of the fastest growing city in south Asia faces several and catastrophic environmental problems related to urban heat. In this study, we reviewed the urban heat island, green roofs techniques and use of remote sensing and GIS extension model to study urban greenery and temperature. The MODIS NDVI, CRU climate and monthly temperature data from 8 meteorological stations during 2000-2016 were used. Mann Kendell test statistic and Sen’s slope were used for the analysis of temperature changes in Kathmandu valley. Beside it, the land use land cover data of 2010 were used and the previous literatures related on Kathmandu valley were reviewed. The air surface temperature has significantly increased at the rate of 0.04°C yr-1 with a maximum temperature trend of 0.06°C. The average annual air surface temperature of Kathmandu valley is 18.06°C with maximum 24.15°C during 2000-2016. In contrary, average annual land surface temperature has ranges from 15.84°C-39.17°C in 2000 and 16°C to 33.98°C in 2014. At the same time, urban area has dramatically increased; averaged LST has more than air surface temperature, Normalized Difference Vegetation Index values has low but normalized difference built up index has high in core urban area. These all environmental consequences are the main factors of urban heat Island in Kathmandu valley. Therefore, green roofs could be an effective mitigation tool to combat environment problems and urban heat island. Though, detail investigation is required to practice green roofs in Kathmandu valley.
影响因子：
6.7
作者：
Kolokotroni, M.;Ren, X.;Mavrogianni, A.
通讯作者：
Mavrogianni, A.