Future scenarios of thermal bioclimatic conditions in a humid tropical city under urban development

Urbanization modifies the heat balance in urban areas and has negative effects on landscape, aesthetics, energy efficiency, human health and the inhabitants’ quality of life. This work evaluated future scenarios of bioclimatic conditions for João Pessoa, a humid tropical city in Northeast Brazil. The scenarios were determined based on trends in air temperature, relative humidity and wind speed for the time period from 1968 to 2015. The study was performed for two distinct periods of three months each (dry and wet seasons) using data from weather stations equipped with thermo-hygrometers and cup anemometers located in nine representative areas of the city. Trends in air temperature, relative humidity, wind speed, and effective temperature index (ET index) time series were evaluated using the Mann-Kendall test. Results indicated that the air temperature showed an increasing trend of 0.34°C/decade, whereas the relative humidity showed a decreasing trend of 0.49%/decade and the wind speed values ranged from 1.3 ms-1 to 3.80 ms-1. These trends are statistically significant according to the Mann-Kendall test (p<0.05). The air temperature increased between the 1980s and 2010s, which corresponds to a period of rapid urbanization of the city. Future environmental conditions in João Pessoa will be determined in accordance with the urbanization processes.

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Influência da Urbanização no Clima da Cidade de Campina Grande-PB (Influence of Urbanization on Climate of the Campina Grande City–PB)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v4i1.232710 ◽

2011 ◽

Vol 4 (1) ◽

pp. 134 ◽

Cited By ~ 2

Author(s):

Francisco de Assis Salviano de Sousa ◽

Heliene Ferreira de Morais ◽

Vicente De Paulo Rodrigues da

Keyword(s):

Time Series ◽

Relative Humidity ◽

Air Temperature ◽

Anthropogenic Activities ◽

Urban Climate ◽

Kendall Test ◽

Annual Rainfall ◽

Abrupt Changes ◽

Mann Kendall Test ◽

Deviation Coefficient

A expansão de cidades produz diversos impactos no ambiente urbano causado por atividades antropogênicas. Este estudo avaliou o efeito da urbanização no clima da cidade de Campina Grande com base em dados mensais de temperatura média do ar, precipitação pluvial, umidade relativa do ar e insolação no período de 1963 a 2004. O método de desvios cumulativos foi utilizado para detectar mudanças abruptas nas séries temporais. Dois períodos de estudo foram estabelecidos: pré-urbano intenso PRÉ-UI (1963-1985) e pós-urbano intenso PÓS-UI (1986-2004). Para cada variável climática foram obtidas estatísticas como: médias, desvio-padrão, coeficiente de variação (CV) e autocorrelação serial. Foram avaliadas as diferenças entre as médias dos períodos PRÉ-UI e PÓS-UI através do teste de t-Student. Também foi usado o teste Mann-Kendall para avaliar as tendências das séries temporais no período total estudado. A temperatura média do ar apresentou tendência crescente, enquanto umidade relativa apresentou tendência decrescente, todas estatisticamente significativas ao nível de 1% através do teste de Mann-Kendall. A série de precipitação pluvial não apresentou tendência estatisticamente significativa. A variabilidade da precipitação pluvial intra-anual, expressa pelo CV, é muito alta e variou de 30 a 89% durante o período analisado. A variabilidade anual da precipitação pluvial é cerca de 30% da variabilidade intra-anual. A temperatura do ar demonstrou persistência natural através dos valores do coeficiente de autocorrelação, para os primeiros lags.Palavras-chave: Clima urbano, Mann-Kendall e variáveis climáticas Influence of Urbanization on Climate of the Campina Grande City–PB ABSTRACTThe expansion of cities produces different impacts in the urban environment caused by anthropogenic activities. This study evaluated the effect of urbanization on climate of the Campina Grande city based on monthly data of average air temperature, rainfall, relative humidity and sunshine in the period 1963 to 2004. The cumulative deviation method was used to detect abrupt changes in time series. Two study periods were established: intense urban pre-PRE-UI (1963-1985) and after intense urban POST-IU (1986-2004). For each climate variable, statistics were obtained as averages, standard deviation, coefficient of variation (CV) and serial autocorrelation. We evaluated the differences between the mean pre-and post-IU through the IU Student t test. It was also used Mann-Kendall test to assess trends in time series over the entire period studied. The average air temperature showed an ascending trend, while relative humidity showed a declining trend, all statistically significant at 1% through the Mann-Kendall test. The series of rainfall did not show a statistically significant trend. The variability of intra-annual precipitation, expressed as CV, is very high and ranged from 30 to 89% during the period analyzed. The variability of annual rainfall is about 30% of intra-annual variability.The air temperature showed persistence through the natural values the autocorrelation coefficient for the first lags. Keywords: Urban climate, Mann-Kendall and climatic variables

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Thermo-hygrometric modeling using ENVI-met® software to an urban park in Cuiabá – Brazil

Ciência e Natura ◽

10.5902/2179460x29510 ◽

2018 ◽

Vol 40 ◽

pp. 37

Author(s):

Thiago D'Orazio Joaquim ◽

Jonathan Willian Zangeski Novais ◽

Levi Pires de Andrade ◽

Karyna De Andrade Carvalho Rosseti ◽

Maricéia Tatiana Vilani ◽

...

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Urban Areas ◽

Urban Park ◽

Hot Climate ◽

Two Phases ◽

The City ◽

City Park

Climate in urban areas, not under the effect of vegetation, was investigated and its benefits were observed in both vegetated and un-vegetated areas. The objective of this research was to model the air temperature and relative humidity using the Software ENVI-met® in an urban park in Cuiabá. The development of the methodology of this work involved two phases: survey (microclimate) and simulation. The microclimate survey was conducted through a mobile transect, for the periods of January 2014 to March 2014 (hot/wet) and July 2015 to September 2015 (hot/dry). The simulation was developed using ENVI-met® software during these two periods of the year. Generally maximizing the parameters, the ENVI-met® model for microclimate varied in the presence of too much vegetation. Simulations showed an increase in temperature and relative humidity in areas not surrounding the Mãe Bonifacia City Park, and this was particularly apparent in areas laid with asphalt and concrete. Vegetated parks play an important role in how hot climate thermoregulatory agents behave in the city of Cuiabá and the surrounding region.

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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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Empirical Equations to Estimate Evapotranspiration in Mosul City

Tikrit Journal of Engineering Sciences ◽

10.25130/tjes.27.4.10 ◽

2020 ◽

Vol 27 (4) ◽

pp. 98-102

Author(s):

Haqqi Yasin ◽

Luma Abdullah

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Air Temperature ◽

Reference Evapotranspiration ◽

Sunshine Duration ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Daily Data ◽

Daily Sunshine ◽

Measured Wind Speed

Average daily data of solar radiation, relative humidity, wind speed and air temperature from 1980 to 2008 are used to estimate the daily reference evapotranspiration in the Mosul City, North of Iraq. ETo calculator software with the Penman Monteith method standardized by the Food and Agriculture Organization is used for calculations. Further, a nonlinear regression approach using SPSS Statistics is utilized to drive the daily reference evapotranspiration relationships in which ETo is function to one or more of the average daily air temperature, actual daily sunshine duration, measured wind speed at 2m height and relative humidity

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A High-Resolution Monitoring Approach of Canopy Urban Heat Island using Random Forest Model and Multi-platform Observations

10.5194/amt-2021-301 ◽

2021 ◽

Author(s):

Shihan Chen ◽

Yuanjian Yang ◽

Fei Deng ◽

Yanhao Zhang ◽

Duanyang Liu ◽

...

Keyword(s):

High Resolution ◽

Random Forest ◽

Urban Heat Island ◽

Air Temperature ◽

Anthropogenic Heat ◽

Heat Island ◽

Model Framework ◽

Rapid Urbanization ◽

Urban Heat ◽

The City

Abstract. Due to rapid urbanization and intense human activities, the urban heat island (UHI) effect has become a more concerning climatic and environmental issue. A high spatial resolution canopy UHI monitoring method would help better understand the urban thermal environment. Taking the city of Nanjing in China as an example, we propose a method for evaluating canopy UHI intensity (CUHII) at high resolution by using remote sensing data and machine learning with a Random Forest (RF) model. Firstly, the observed environmental parameters [e.g., surface albedo, land use/land cover, impervious surface, and anthropogenic heat flux (AHF)] around densely distributed meteorological stations were extracted from satellite images. These parameters were used as independent variables to construct an RF model for predicting air temperature. The correlation coefficient between the predicted and observed air temperature in the test set was 0.73, and the average root-mean-square error was 0.72 °C. Then, the spatial distribution of CUHII was evaluated at 30-m resolution based on the output of the RF model. We found that wind speed was negatively correlated with CUHII, and wind direction was strongly correlated with the CUHII offset direction. The CUHII reduced with the distance to the city center, due to the de-creasing proportion of built-up areas and reduced AHF in the same direction. The RF model framework developed for real-time monitoring and assessment of high-resolution CUHII provides scientific support for studying the changes and causes of CUHII, as well as the spatial pattern of urban thermal environments.

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Analyzing the Issue of On-street Parking in Commercial Areas: A Case Study of the City of Hyderabad, Pakistan

Journal of Art Architecture and Built Environment ◽

10.32350/jaabe.12.01 ◽

2018 ◽

Vol 01 (02) ◽

pp. 01-09

Author(s):

Baig Farrukh ◽

Sahito Noman ◽

Bano Arsla ◽

Keyword(s):

Traffic Congestion ◽

Urban Areas ◽

Survey Methodology ◽

Greenhouse Gas Emission ◽

Central Business District ◽

Rapid Urbanization ◽

Analysis Technique ◽

Business District ◽

Public Views ◽

The City

In developing countries, rapid urbanization has created an enormous pressure on land use, infrastructure and transportation. The fast growing ratio of motorized vehicles in urban areas is the main cause of environmental degradation. Almost 80% of the greenhouse gas emission is from vehicles in cities. In the city centers, on-street parking is considered the major cause of traffic congestion. The aim of this study was to evaluate the problems of on-street parking and disorderly parking at Central Business District (CBD) of Hyderabad city. The field survey methodology was adopted to perceive the current traffic problems in the city center and traffic count survey was carried out in both peak and off hours. The data was analyzed using descriptive statistics frequency analysis technique with the help of Statistical Package for the Social Sciences (SPSS). The findings revealed that increasing number of vehicles, on-street parking, improper parking, encroachment, inadequate parking space and poor condition of roads are the main causes of traffic congestion. The study bridges up the research gap of determining public views about on-street parking challenges in the context of Hyderabad, Pakistan and provides statistical results which may equally be adapted by policy makers and transportation planners in order to improve the traffic situation.

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Abandoned Farmland Location in Areas Affected by Rapid Urbanization Using Textural Characterization of High Resolution Aerial Imagery

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi9040191 ◽

2020 ◽

Vol 9 (4) ◽

pp. 191 ◽

Cited By ~ 2

Author(s):

Juan José Ruiz-Lendínez

Keyword(s):

Urban Areas ◽

Spatial Information ◽

Arable Land ◽

Aerial Imagery ◽

Rapid Urbanization ◽

Abandoned Farmland ◽

Textural Characterization ◽

Study Results ◽

Abandoned Land ◽

The City

Several studies have demonstrated that farmland abandonment occurs not only in rural areas, but is also closely interlinked with urbanization processes. Therefore, the location of abandoned land and the registration of the spatial information referring to it play important roles in urban land management. However, mapping abandoned land or land in the process of abandonment is not an easy task because the limits between the different land uses are not clear and precise. It is therefore necessary to develop methods that allow estimating and mapping this type of land as accurately as possible. As an alternative to other geomatics methods such as satellite remote sensing, our approach proposes a framework for automatically locating abandoned farmland in urban landscapes using the textural characterization and segmentation of aerial imagery. Using the city of Poznań (Poland) as a case study, results demonstrated the feasibility of applying our approach, reducing processing time and workforce resources. Specifically and by comparing the results obtained with the data provided by CORINE Land Cover, 2275 ha (40.3%) of arable land within the city limits were abandoned, and the area of abandoned arable land was almost 9.2% of the city’s area. Finally, the reliability of the proposed methodology was assessed from two different focuses: (i) the accuracy of the segmentation results (from a positional point of view) and (ii) the efficiency of locating abandoned land (as a specific type of land use) in urban areas particularly affected by rapid urbanization.

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The atmospheric conditions affecting sporulation of blue mould in tobacco

Australian Journal of Experimental Agriculture ◽

10.1071/ea9640178 ◽

1964 ◽

Vol 4 (13) ◽

pp. 178 ◽

Cited By ~ 2

Author(s):

BG Collins

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Air Temperature ◽

Critical Parameter ◽

Leaf Surface ◽

Atmospheric Conditions ◽

Blue Mould ◽

Growing Seasons ◽

Ambient Relative Humidity ◽

Critical Relative Humidity

Conditions favouring sporulation of blue mould (Peronospora tabacina Adam) having been established in the laboratory, a theoretical model has now been used to express the critical parameter, i.e. the relative humidity near the leaf surface where the spores form, in terms of the ambient atmospheric conditions. To test the validity of this model, wind speed, air temperature, and relative humidity mere measured over four growing seasons in three tobacco crops in the Ovens Valley, Victoria, and related to times of sporulation of the mould observed concurrently in these crops. 'Critical relative humidity,' a function of wind speed, air temperature, and heat loss from the crop is shown to be a more serviceable indicator of likelihood of sporulation than either ambient relative humidity or rainfall.

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Study on Land-use Changes and Their Impacts on Air Pollution in Chengdu

Atmosphere ◽

10.3390/atmos11010042 ◽

2019 ◽

Vol 11 (1) ◽

pp. 42 ◽

Cited By ~ 1

Author(s):

Wei Sun ◽

Zhihong Liu ◽

Yang Zhang ◽

Weixin Xu ◽

Xiaotong Lv ◽

...

Keyword(s):

Land Use ◽

Wind Speed ◽

Correlation Coefficient ◽

Urban Areas ◽

Land Use Changes ◽

Urban Land ◽

Urban Land Use ◽

Simulation Results ◽

The City ◽

Better Than

The expansion of urban areas and the increase in the number of buildings and urbanization characteristics, such as roads, affect the meteorological environment in urban areas, resulting in weakened pollutant dispersion. First, this paper uses GIS (geographic information system) spatial analysis technology and landscape ecology analysis methods to analyze the dynamic changes in land cover and landscape patterns in Chengdu as a result of urban development. Second, the most appropriate WRF (Weather Research and Forecasting) model parameterization scheme is selected and screened. Land-use data from different development stages in the city are included in the model, and the wind speed and temperature results simulated using new and old land-use data (1980 and 2015) are evaluated and compared. Finally, the results of the numerical simulations by the WRF-Chem air quality model using new and old land-use data are coupled with 0.25° × 0.25°-resolution MEIC (Multi-resolution Emission Inventory for China) emission source data from Tsinghua University. The results of the sensitivity experiments using the WRF-Chem model for the city under different development conditions and during different periods are discussed. The meteorological conditions and pollution sources remained unchanged as the land-use data changed, which revealed the impact of urban land-use changes on the simulation results of PM2.5 atmospheric pollutants. The results show the following. (1) From 1980 to 2015, the land-use changes in Chengdu were obvious, and cultivated land exhibited the greatest changes, followed by forestland. Under the influence of urban land-use dynamics and human activities, both the richness and evenness of the landscape in Chengdu increased. (2) The microphysical scheme WSM3 (WRF Single–Moment 3 class) and land-surface scheme SLAB (5-layer diffusion scheme) were the most suitable for simulating temperatures and wind speeds in the WRF model. The wind speed and temperature simulation results using the 2015 land-use data were better than those using the 1980 land-use data when assessed according to the coincidence index and correlation coefficient. (3) The WRF-Chem simulation results obtained for PM2.5 using the 2015 land-use data were better than those obtained using the 1980 land-use data in terms of the correlation coefficient and standard deviation. The concentration of PM2.5 in urban areas was higher than that in the suburbs, and the concentration of PM2.5 was lower on Longquan Mountain in Chengdu than in the surrounding areas.

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Air Temperature Change in the Southern Tarim River Basin, China, 1964–2011

The Scientific World JOURNAL ◽

10.1155/2013/894851 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Benfu Zhao ◽

Jianhua Xu ◽

Zhongsheng Chen ◽

Ling Bai ◽

Peng Li

Keyword(s):

Correlation Analysis ◽

River Basin ◽

Air Temperature ◽

Negative Correlation ◽

Kendall Test ◽

Temperature Data ◽

Tarim River ◽

Tarim River Basin ◽

Change Rate ◽

Mann Kendall Test

The temperature data from 3 meteorological stations (Kashi, Ruoqiang, and Hotan) in the South of Tarim River Basin (STRB) during 1964–2011 were analyzed by Mann-Kendall test and correlation analysis. The results from Mann-Kendall test show that the surface temperature (ST), 850 hPa temperature (T850), and 700 hPa temperature (T700) exhibited upward trends, while 300 hPa temperature (T300) revealed a downward trend. On the whole, the change rate of ST, T850, T700, and T300 was 0.26~0.46°C/10a, 0.15~0.40°C/10a, 0.03~0.10°C/10a, and −0.38~−0.13°C/10a, respectively. For the periods, ST and T850 declined during 1964–1997 and then rose during 1998–2011. T700 declined during 1964–2005 and then rose during 2006–2011, while T300 rose from 1964 to 1970s and then declined. The results from correlation analysis show that T850 and T700 positively correlated with ST (P<0.01) at the all three stations and there was a negative correlation between T300 and ST at Hotan (P<0.1), while the correlation is not significant at Kashi and Ruoqiang. The results indicate that there were gradient differences in the response of upper-air temperature (UT) to ST change.

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