scholarly journals Impacts of the Microclimate of a Large Urban Park on Its Surrounding Built Environment in the Summertime

2021 ◽  
Vol 13 (22) ◽  
pp. 4703
Author(s):  
Majid Amani-Beni ◽  
Biao Zhang ◽  
Gao-Di Xie ◽  
A. Jacob Odgaard
Keyword(s):  
Built Environment ◽  
Land Cover ◽  
Surface Temperature ◽  
Air Temperature ◽  
Green Space ◽  
Thermal Environment ◽  
Ambient Air ◽  
Surrounding Area ◽  
The Impact ◽  
Space Ratio

The cooling effect of green spaces as an ecological solution to mitigate urban climate change is well documented. However, the factors influencing the microclimate in the built environment around forest parks, diurnal variations of their impact and their degree of importance have not been explicitly addressed. We attempted to quantify how much various landscape parameters, including land cover and spatial location, impact the ambient air and surface temperature in the area around Beijing’s Olympic Forest Park. Data were taken along strategically located traverses inside and outside the park. We found: (1) The air temperature during the day was 1.0–3.5 °C lower in the park than in the surrounding area; the surface temperature was 1.7–4.8 °C lower; air humidity in the park increased by 8.7–15.1%; and the human comfort index reduced to 1.8–6.9, all generating a more comfortable thermal environment in the park than in the surrounding area. (2) The distance to the park and the green space ratio of the park’s surrounding area are significant factors for regulating its microclimate. A 1 km increase in distance to the park caused the temperature to increase by 0.83 °C; when the green space ratio increased by 10%, the temperature dropped by 0.16 °C on average. The impact of these two parameters was more obvious in the afternoon than in the middle of the day or in the morning. The green space ratio could be used for designing a more stable thermal environment. (3) Land cover affects surface temperature more than it does air temperature. Our data suggest that an urban plan with an even distribution of green space would provide the greatest thermal comfort.

scholarly journals Urban Temperature Profiles and Land Cover Detection in the Jakarta Metropolitan Area using Remote Sensing

2019 ◽  
Vol 51 (3) ◽  
pp. 357
Author(s):  
Hasti Widyasamratri ◽  
Kazuyoshi Souma ◽  
Tadashi Suetsugi
Keyword(s):  
Land Cover ◽  
Surface Temperature ◽  
Air Temperature ◽  
Land Surface Temperature ◽  
Metropolitan Area ◽  
Land Surface ◽  
Thermal Environment ◽  
Land Cover Classification ◽  
Rapid Urbanization ◽  
Cooling Period

This research aim to investigate the urban thermal environment profile and land cover classification  in the Jakarta Metropolitan Area (JMA) in 1989 and 2013. Thermal environment conducted by installing fix point ground measurement of air temperature and land surface temperature. The land cover classification was carried out  by using Landsat TM 5 and Landsat 7 ETM+ data sets. The diurnal variation of air temperature shows that Urban Heat Island (UHI) was occurring in urban and suburban JMA, which can be seen the slower cooling period in the urban area than suburban areas. Positive correlation between air temperature (Ta) and land surface temperature (Ts) on the brush (r2 = 0.78) and the asphalt surface (r2= 0.88) is clearly shown during the study. The rapid urbanization was detected during 1989 to 2013 where the urban sprawl is spread over to the whole area of JMA. Urban built up is the dominant of high increase due to years, while vegetation is decreasing.    

Regression Analysis of the Relationship between Urban Heat Island Effect and Urban Canopy Characteristics in a Mountainous City, Chongqing

2012 ◽  
Vol 21 (6) ◽  
pp. 821-836 ◽  
Author(s):  
Jun Lu ◽  
Chundie Li ◽  
Chuck Yu ◽  
Ming Jin ◽  
Shaowei Dong
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Air Temperature ◽  
Thermal Environment ◽  
Linear Regression Analysis ◽  
Urban Canopy ◽  
Ambient Air ◽  
Multivariate Linear Regression Analysis ◽  
Correlation Degree ◽  
The Impact

In order to guide the urban planning of thermal environment in a mountainous city, this paper reports a study which investigated the impact of four canopy characteristics: impermeable rate (IR), building density (BD), water body percentage (WBP) and planting rate (PR), on the average ambient air temperature (AAT) within seven built-up areas in the metropolitan city of Chongqing. A rural area was also monitored as a control for the investigation. Oziexplorer was used to measure the IR, BD, WP and PR within a radius of 100 m to 500 m of the locations investigated. Univariate linear regression was used to determine the correlation degree (CD) between each canopy characteristics and AAT. Different trends were observed and this correlated with the increasing radius of different sites. The maximum correlation coefficient between IR and AAT was observed within a 100-m radius of the investigated site. It was found that with an increase of radius, the influence of IR on AAT became weaker. The influence of BD on AAT became more significant and reached a maximum within 250 m radius. The multivariate linear regression analysis has illustrated the order of importance of canopy characteristics as: IR > WBP > PR > BD on daily mean air temperature within a 100-m radius of the locations investigated in Shapingba, Chongqing.

scholarly journals The Impact of Microclimate on the Reproductive Phenology of Female Populus tomentosa in a Micro-Scale Urban Green Space in Beijing

2021 ◽  
Vol 13 (6) ◽  
pp. 3518
Author(s):  
Xiaoyi Xing ◽  
Li Dong ◽  
Cecil Konijnendijk ◽  
Peiyao Hao ◽  
Shuxin Fan ◽  
...  
Keyword(s):  
Seed Dispersal ◽  
Spatial Variation ◽  
Air Temperature ◽  
Green Space ◽  
Populus Tomentosa ◽  
Early Spring ◽  
Reproductive Phenology ◽  
Primary Role ◽  
Micro Scale ◽  
The Impact

The spatial variation of poplars’ reproductive phenology in Beijing’s urban area has aggravated the threat of poplar fluff (cotton-like flying seeds) to public health. This research explored the impact of microclimate conditions on the reproductive phenology of female Populus tomentosa in Taoranting Park, a micro-scale green space in Beijing (range <1 km). The observed phenophases covered flowering, fruiting, and seed dispersal, and ENVI-MET was applied to simulate the effect of the microclimate on SGS (start day of the growing season). The results showed that a significant spatial variation in poplar reproductive phenology existed at the research site. The variation was significantly affected by the microclimate factors DMT (daily mean temperature) and DMH (daily mean heat transfer coefficient), with air temperature playing a primary role. Specifically, the phenology of flowering and fruiting phenophases (BBB, BF, FF, FS) was negatively correlated with DMT (−0.983 ≤ r ≤ −0.908, p <0.01) and positively correlated with DMH (0.769 ≤ r ≤ 0.864, p < 0.05). In contrast, DSD (duration of seed dispersal) showed a positive correlation with DMT (r = 0.946, p < 0.01) and a negative correlation with DMH (r = −0.922, p < 0.01). Based on the findings, the increase in air convection with lower air temperature and decrease in microclimate variation in green space can be an effective way to shorten the seed-flying duration to tackle poplar fluff pollution in Beijing’s early spring.

scholarly journals Impact of Multitemporal Land Use and Land Cover Change on Land Surface Temperature Due to Urbanization in Hefei City, China

2021 ◽  
Vol 10 (12) ◽  
pp. 809
Author(s):  
Jing Sun ◽  
Suwit Ongsomwang
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Surface Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Urban Areas ◽  
Decomposition Analysis ◽  
Lulc Change ◽  
Main Components ◽  
The Impact

Land surface temperature (LST) is an essential parameter in the climate system whose dynamics indicate climate change. This study aimed to assess the impact of multitemporal land use and land cover (LULC) change on LST due to urbanization in Hefei City, Anhui Province, China. The research methodology consisted of four main components: Landsat data collection and preparation; multitemporal LULC classification; time-series LST dataset reconstruction; and impact of multitemporal LULC change on LST. The results revealed that urban and built-up land continuously increased from 2.05% in 2001 to 13.25% in 2020. Regarding the impact of LULC change on LST, the spatial analysis demonstrated that the LST difference between urban and non-urban areas had been 1.52 K, 3.38 K, 2.88 K and 3.57 K in 2001, 2006, 2014 and 2020, respectively. Meanwhile, according to decomposition analysis, regarding the influence of LULC change on LST, the urban and built-up land had an intra-annual amplitude of 20.42 K higher than other types. Thus, it can be reconfirmed that land use and land cover changes due to urbanization in Hefei City impact the land surface temperature.

scholarly journals Quantifying the Effects of Urban Form on Land Surface Temperature in Subtropical High-Density Urban Areas Using Machine Learning

2019 ◽  
Vol 11 (8) ◽  
pp. 959 ◽  
Author(s):  
Yanwei Sun ◽  
Chao Gao ◽  
Jialin Li ◽  
Run Wang ◽  
Jian Liu
Keyword(s):  
Surface Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Urban Form ◽  
Urban Areas ◽  
Thermal Environment ◽  
High Density ◽  
Cooling Effects ◽  
Urban Thermal Environment ◽  
The Impact

It is widely acknowledged that urban form significantly affects urban thermal environment, which is a key element to adapt and mitigate extreme high temperature weather in high-density urban areas. However, few studies have discussed the impact of physical urban form features on the land surface temperature (LST) from a perspective of comprehensive urban spatial structures. This study used the ordinary least-squares regression (OLS) and random forest regression (RF) to distinguish the relative contributions of urban form metrics on LST at three observation scales. Results of this study indicate that more than 90% of the LST variations were explained by selected urban form metrics using RF. Effects of the magnitude and direction of urban form metrics on LST varied with the changes of seasons and observation scales. Overall, building morphology and urban ecological infrastructure had dominant effects on LST variations in high-density urban centers. Urban green space and water bodies demonstrated stronger cooling effects, especially in summer. Building density (BD) exhibited significant positive effects on LST, whereas the floor area ratio (FAR) showed a negative influence on LST. The results can be applied to investigate and implement urban thermal environment mitigation planning for city managers and planners.

The impact of increased temperatures on germination patterns of semi-aquatic plants

2019 ◽  
Vol 29 (3) ◽  
pp. 204-209
Author(s):  
Jade Dessent ◽  
Susan Lawler ◽  
Daryl Nielsen
Keyword(s):  
Soil Temperature ◽  
Air Temperature ◽  
Soil Seed Bank ◽  
Ambient Air ◽  
Future Climate Change ◽  
Ambient Air Temperature ◽  
Threshold Temperatures ◽  
Soil Temperatures ◽  
The Impact ◽  
Number Of Seeds

AbstractFuture climate change predictions indicate that there will be an increase in ambient air temperature. Increases in ambient air temperature will result in a corresponding increase in soil temperature. The consequences of further increases in soil temperature will potentially be detrimental for the soil seed bank of plants in terms of length of dormancy and viability of seeds. This experiment investigated the effect of different exposure temperatures and duration of exposure on the germination of semi-aquatic plant species. Seeds of four species (Alternanthera denticulata, Juncus usitatus, Persicaria lapathifolia and Persicaria prostrata) were exposed to temperatures ranging from 25 to 100°C for durations between 1 and 14 days, before being germinated in an incubator for 6 weeks. Germination occurred in all four species after exposure to temperatures ranging from 25 to 60°C. These temperatures appeared to promote germination as the temperature and duration of exposure increased. However, in P. lapathifolia and P. prostrata, the number of seeds germinating declined when exposed to 70°C and there was no germination for temperatures exceeding this. In contrast, A. denticulata and J. usitatus only began to decline when exposed to 80°C, with no germination at higher temperatures. These results suggest that soil temperatures exceeding potential threshold temperatures of 70 and 80°C will result in a decline in the number of seeds germinating and may potentially see a change in species distributions. As such soil temperatures are already being experienced throughout Australia, some species may already be close to their thermal threshold.

Study on Urban Thermal Environment based on Diurnal Temperature Range

2020 ◽  
Author(s):  
Zheng Guo ◽  
Miaomiao Cheng
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Thermal Environment ◽  
Surface Air Temperature ◽  
Heat Island ◽  
Near Surface ◽  
Diurnal Range ◽  
Urban Thermal Environment

&lt;p&gt;Diurnal temperature range (includes land surface temperature diurnal range and near surface air temperature diurnal range) is an important meteorological parameter, which is a very important factor in the field of the urban thermal environmental. Nowadays, the research of urban thermal environment mainly focused on surface heat island and canopy heat island.&lt;/p&gt;&lt;p&gt;Based on analysis of the current status of city thermal environment. Firstly, a method was proposed to obtain near surface air temperature diurnal range in this study, difference of land surface temperature between day and night were introduced into the improved temperature vegetation index feature space based on remote sensing data. Secondly, compared with the district administrative division, we analyzed the spatial and temporal distribution characteristics of the diurnal range of land surface temperature and near surface air temperature.&lt;/p&gt;&lt;p&gt;The conclusions of this study are as follows:&lt;/p&gt;&lt;p&gt;1 During 2003-2012s, the land surface temperature and near surface air temperature diurnal range of Beijing were fluctuating upward. The rising trend of the near surface air temperature diurnal range was more significant than land surface temperature diurnal range. In addition, the rise and decline of land surface temperature and near surface air temperature diurnal range in different districts were different. In the six city districts, the land surface temperature and near surface air temperature diurnal range in the six areas of the city were mainly downward. The decline trend of near surface air temperature diurnal range was more significant than land surface temperature diurnal range.&lt;/p&gt;&lt;p&gt;2 During 2003-2012s, the land surface temperature and near surface air temperature diurnal range of Beijing with similar characteristics in spatial distribution, with higher distribution land surface temperature and near surface air temperature diurnal range in urban area and with lower distribution of land surface temperature and near surface air temperature diurnal range in the Northwest Mountainous area and the area of Miyun reservoir.&lt;/p&gt;

Towards Pedestrian Microclimatic Comfort: A Rapid Predication Model for Street Winds and Pedestrian Thermal Sensation

Nano LIFE ◽  
2018 ◽  
Vol 08 (02) ◽  
pp. 1840006
Author(s):  
Jing Li ◽  
Mengnan Qi ◽  
Qiuhua Duan ◽  
Lei Huo ◽  
Julian Wang
Keyword(s):  
Wind Speed ◽  
Built Environment ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Goodness Of Fit ◽  
Comfort Level ◽  
Outdoor Thermal Comfort ◽  
Design Parameters ◽  
Rapid Urbanization ◽  
The Impact

Significant changes in the urban built environment have occurred due to rapid urbanization and increases in the urban population. Such alterations may produce environmental health-related issues such as urban heat stress, air pollution and traffic noise. This research undertook a field study to collect data including urban design parameters, micro-environmental factors and city climatic information. This work was conducted over a two-year period on three pedestrian streets located in high-density urban areas in Beijing. These areas were selected in order to study the influences of urban street canyon texture within a particular geometric layout, wind flow corridors and variations in air temperature on pedestrian microclimatic comfort. The results will facilitate the work of urban planners by providing them with information for use in improving outdoor thermal comfort through their designs. A total of 60[Formula: see text]485 samples were organized into training, validation and test sets. We confirmed our hypothesis that internal wind speed ([Formula: see text] is attributable mainly to the urban texture coefficient ([Formula: see text], air temperature ([Formula: see text] and leading-in wind speed ([Formula: see text]. The model was tested using the test data collected onsite, which demonstrated a very accurate goodness-of-fit; the model achieved an R-squared value of 0.82, which meant that [Formula: see text] as a dependent variable was 82% correlated to the three predictors as independent variables. With this computer simulation, urban planners can now predict and visualize the impact of changes on the built environment in terms of either the direction of solar radiation received or increases in wind speed, in return for the desired thermal comfort level for residents of the neighborhood.

Research on Correlation between Surface Temperature and Nearby Air Temperature of the Underlay

2012 ◽  
Vol 209-211 ◽  
pp. 210-214 ◽  
Author(s):  
Xu Yuan ◽  
Qiong Li ◽  
Qing Lin Meng
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Thermal Environment ◽  
Urban Climate ◽  
Wave Radiation ◽  
Heat Island ◽  
Island Effect ◽  
Long Wave ◽  
Environment Temperature ◽  
Atmosphere Environment

In the research on urban climate, “heat island effect” is the key point, which directly affects the buildings of city, the traffic, and people's daily life.[1]One important performance of the "heat island effect" is that the bottom atmosphere environment temperature is high, especially the air temperature near the underlay surface, namely air temperature 1.5m high. In the thermal environment which influences people's living and working, air temperature 1.5m high is the most important and direct. [2] It rises mainly by the absorption of the long wave radiation reflected by the underlay surface. So the type of underlay has a very important influence to the air temperature 1.5m high. The underlay surface temperature and the air temperature 1.5m high have a certain grade correlation. This paper is written for the research on the correlation.

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