A Coupled Modelling Method for the Evaluation of the Impact of Pavement Solar Collector on Urban Air Temperature and Thermal Collection

The changing climate has introduced new and unique challenges and threats to humans and their environment. Urban dwellers in particular have suffered from increased levels of heat stress, and the situation is predicted to continue to worsen in the future. Attention toward urban climate change adaptation has increased more than ever before, but previous studies have focused on indoor and outdoor temperature patterns separately. The objective of this research is to assess the indoor and outdoor temperature patterns of different urban settlements. Remote sensing data, together with air temperature data collected with temperature data loggers, were used to analyze land surface temperature (outdoor temperature) and air temperature (indoor temperature). A hot and cold spot analysis was performed to identify the statistically significant clusters of high and low temperature data. The results showed a distinct temperature pattern across different residential units. Districts with dense urban settlements show a warmer outdoor temperature than do more sparsely developed districts. Dense urban settlements show cooler indoor temperatures during the day and night, while newly built districts show cooler outdoor temperatures during the warm season. Understanding indoor and outdoor temperature patterns simultaneously could help to better identify districts that are vulnerable to heat stress in each city. Recognizing vulnerable districts could minimize the impact of heat stress on inhabitants.

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Seasonally changing contribution of sea ice and snow cover to uncertainty in multi-decadal Eurasian surface air temperature trends based on CESM simulations

Climate Dynamics ◽

10.1007/s00382-021-05746-4 ◽

2021 ◽

Author(s):

Zhaomin Ding ◽

Renguang Wu

Keyword(s):

Sea Ice ◽

Air Temperature ◽

Western Siberia ◽

Russian Far East ◽

Far East ◽

Surface Air Temperature ◽

The Caspian Sea ◽

Sea Ice Concentration ◽

Northern Siberia ◽

The Impact

AbstractThis study investigates the impact of sea ice and snow changes on surface air temperature (SAT) trends on the multidecadal time scale over the mid- and high-latitudes of Eurasia during boreal autumn, winter and spring based on a 30-member ensemble simulations of the Community Earth System Model (CESM). A dynamical adjustment method is used to remove the internal component of circulation-induced SAT trends. The leading mode of dynamically adjusted SAT trends is featured by same-sign anomalies extending from northern Europe to central Siberia and to the Russian Far East, respectively, during boreal spring and autumn, and confined to western Siberia during winter. The internally generated component of sea ice concentration trends over the Barents-Kara Seas contributes to the differences in the thermodynamic component of internal SAT trends across the ensemble over adjacent northern Siberia during all the three seasons. The sea ice effect is largest in autumn and smallest in winter. Eurasian snow changes contribute to the spread in dynamically adjusted SAT trends as well around the periphery of snow covered region by modulating surface heat flux changes. The snow effect is identified over northeast Europe-western Siberia in autumn, north of the Caspian Sea in winter, and over eastern Europe-northern Siberia in spring. The effects of sea ice and snow on the SAT trends are realized mainly by modulating upward shortwave and longwave radiation fluxes.

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

Sustainability ◽

10.3390/su13063518 ◽

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.

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The impact of COVID-19 pandemic in Mediterranean urban air pollution and mobility

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567036.2021.1895373 ◽

2021 ◽

pp. 1-16

Author(s):

Nikolaos Sifakis ◽

Maria Aryblia ◽

Tryfon Daras ◽

Stavroula Tournaki ◽

Theocharis Tsoutsos

Keyword(s):

Air Pollution ◽

Urban Air Pollution ◽

Urban Air ◽

The Impact

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Quantifying the Independent Influences of Land Cover and Humidity on Microscale Urban Air Temperature Variation in Hot Summer: Methods of Path Analysis and Genetic SVR

Atmosphere ◽

10.3390/atmos11121377 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1377

Author(s):

Weifang Shi ◽

Nan Wang ◽

Aixuan Xin ◽

Linglan Liu ◽

Jiaqi Hou ◽

...

Keyword(s):

Relative Humidity ◽

Land Cover ◽

Path Analysis ◽

Temperature Variation ◽

Direct Effect ◽

Air Temperature ◽

Urban Areas ◽

Support Vector ◽

Urban Air ◽

Air Temperatures

Mitigating high air temperatures and heat waves is vital for decreasing air pollution and protecting public health. To improve understanding of microscale urban air temperature variation, this paper performed measurements of air temperature and relative humidity in a field of Wuhan City in the afternoon of hot summer days, and used path analysis and genetic support vector regression (SVR) to quantify the independent influences of land cover and humidity on air temperature variation. The path analysis shows that most effect of the land cover is mediated through relative humidity difference, more than four times as much as the direct effect, and that the direct effect of relative humidity difference is nearly six times that of land cover, even larger than the total effect of the land cover. The SVR simulation illustrates that land cover and relative humidity independently contribute 16.3% and 83.7%, on average, to the rise of the air temperature over the land without vegetation in the study site. An alternative strategy of increasing the humidity artificially is proposed to reduce high air temperatures in urban areas. The study would provide scientific support for the regulation of the microclimate and the mitigation of the high air temperature in urban areas.

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Comparing different approaches for assessing the impact of COVID-19 lockdown on urban air quality in Reading, UK

Atmospheric Research ◽

10.1016/j.atmosres.2021.105730 ◽

2021 ◽

pp. 105730

Author(s):

Said Munir ◽

Zhiwen Luo ◽

Tim Dixon

Keyword(s):

Air Quality ◽

Urban Air Quality ◽

Urban Air ◽

The Impact

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The impact of urbanization on air temperature across China

Theoretical and Applied Climatology ◽

10.1007/s00704-007-0339-8 ◽

2007 ◽

Vol 93 (3-4) ◽

pp. 179-194 ◽

Cited By ~ 100

Author(s):

L. J. Hua ◽

Z. G. Ma ◽

W. D. Guo

Keyword(s):

Air Temperature ◽

Impact Of Urbanization ◽

The Impact

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Transmission of solar radiation through clouds on melting glaciers: a comparison of parameterizations and their impact on melt modelling

Journal of Glaciology ◽

10.3189/002214311796406013 ◽

2011 ◽

Vol 57 (202) ◽

pp. 367-381 ◽

Cited By ~ 42

Author(s):

Francesca Pellicciotti ◽

Thomas Raschle ◽

Thomas Huerlimann ◽

Marco Carenzo ◽

Paolo Burlando

Keyword(s):

Solar Radiation ◽

Air Temperature ◽

Radiative Forcing ◽

Model Performance ◽

Horizontal Resolution ◽

Swiss Alps ◽

Cloud Radiative Forcing ◽

Correct Definition ◽

Diurnal Range ◽

The Impact

AbstractWe explore the robustness and transferability of parameterizations of cloud radiative forcing used in glacier melt models at two sites in the Swiss Alps. We also look at the rationale behind some of the most commonly used approaches, and explore the relationship between cloud transmittance and several standard meteorological variables. The 2 m air-temperature diurnal range is the best predictor of variations in cloud transmittance. However, linear and exponential parameterizations can only explain 30–50% of the observed variance in computed cloud transmittance factors. We examine the impact of modelled cloud transmittance factors on both solar radiation and ablation rates computed with an enhanced temperature-index model. The melt model performance decreases when modelled radiation is used, the reduction being due to an underestimation of incoming solar radiation on clear-sky days. The model works well under overcast conditions. We also seek alternatives to the use of in situ ground data. However, outputs from an atmospheric model (2.2 km horizontal resolution) do not seem to provide an alternative to the parameterizations of cloud radiative forcing based on observations of air temperature at glacier automatic weather stations. Conversely, the correct definition of overcast conditions is important.

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