POSTER 17: GD - Urban climatology studies and link with CC trends
EL RÉGIMEN BIOCLIMÁTICO MEDIO DE LA CIUDAD DE NATAL, BRASIL CON EL UNIVERSAL THERMAL CLIMATE INDEX (UTCI)
Federal Institute of Rio Grande do Norte, Brazil
Este estudio tiene como objetivo el análisis del régimen bioclimático de la ciudad de Natal a través del análisis de los datos de las series largas y de los transectos de campo. Para obtener el régimen de confort térmico de la ciudad se han utilizadas las temperaturas máximas y mínimas de los datos de las series diarias del período 1995 a 2010 del observatorio urbano, como también los datos medidos en los transectos del año de 2011 (julio y octubre), de 2012 (enero, abril, julio y octubre) y en enero de 2013.
El índice de confort térmico utilizado ha sido el Índice Universal de Confort Térmico (Universal Thermal Climate Index, UTCI), obtenido mediante el programa Bioklima 2.6 (Blazejczyk, 2010).
El urbanismo bioclimático se entiende como un área urbana singular caracterizada por la adecuación de sus trazados urbanos a las condiciones del clima local. (Higueras, 2006). La ciudad de Natal no fue una ciudad totalmente planeada en términos de un urbanismo bioclimático y continúa sin serlo. Al contrario, ha pasado desde su fundación por cambios muy significativos en su área territorial, sin un adecuado planeamiento urbano bioclimático, además se queda merced de la especulación inmobiliaria. La importancia de conocer el régimen bioclimático de la ciudad es un paso importante para definir las estrategias de mitigación de los problemas del clima urbano.
En este contexto se presenta el estudio y se define el año bioclimático medio de la ciudad de Natal encuadrado en las sensaciones térmicas máximas y mínimas para el año medio con el índice de confort térmico universal (UTCI). Ambos resultados permitieron calificar el confort térmico que siente la población de Natal.
El régimen diario predomina la sensación de fuerte estrés por calor (32 a 38°C) durante el periodo diurno y por las noches el estrés moderado por calor (26 a 32°C), así los días son calurosos y las noches son agradables y frescas.
El régimen bioclimático medio de Natal muestra que los meses de febrero, marzo, abril y mayo son los meses más cálidos, mientras que julio y agosto son los meses más frescos. Las tendencias bioclimáticas de Natal muestran que en la sensación de confort térmico del UTCI de las máximas prevalece el estrés por calor y para las mínimas el estrés moderado por el calor. En una visión amplia del confort térmico, la sensación de estrés moderado por el calor es la que más se encuadra, pero en los último años empieza a aparecer el nivel de estrés fuerte por calor en la ciudad de Natal.
El análisis del régimen bioclimático medio de Natal hace frente a las nuevas líneas de investigación en priorizar la bioclimatología en los estudios de clima urbano. La aplicación de un índice de confort térmico es esencial para el conocimiento de las sensaciones térmicas del ambiente urbano además de mejorar la gestión y el desarrollo sostenible del ambiente urbano.
Evaluating the Long-term Climatic changes and its impact on human thermal comfort in few rapidly growing cities of state of Gujarat, India
1Department of Civil Engineering, Indus University, Ahmedabad, India; 2Department of Architecture and Planning, Visvesvaraya National Institute of Technology, Nagpur
With the onset of development, the urban areas have, no doubt, become the engines of economic growth and the magnets for new residents flooding in from rural areas but the rapid industrialization and urbanization has several impacts on urban environment. The urbanization process has resulted in climate changes as a result of its radioactive, thermal and aerodynamics characteristics. These changes have deteriorated the living environment, increased the energy consumption, elevated the ground level ozone and even increased the mortality rates. It is in this background an attempt has been made to evaluate the changing climate of 6 cities of Gujarat namely Ahmedabad, Baroda, Surat, Rajkot, Bhuj and Daman which are rapidly developing.
The meteorology parameters like the dry bulb temperature, wet bulb temperature, wind speed and relative humidity which are the key aspects of a climate were statistically studied for a period of 37 years during 1969-2006. The availability of the meteorological data was at a frequency of every three hours. The impact of these changing meteorological parameters on human thermal comfort was studied using biometeorological indices.
In the background of the urbanizing phenomenon, the present study thus attempts to quantify the artificially induced climatic trends affecting the human beings.
SPATIOTEMPORAL ANALYSIS ON THE SQUATTER DEVELOPMENT: A CASE STUDY IN KAMPUNG BARU, KUALA LUMPUR
Universiti Teknologi Malaysia, Malaysia
As a Malay Agricultural Settlement gazetted in 1900, Kampung Baru, Kuala Lumpur has been a subject of prolonged national interests (e.g. economic, social, environment and politic) and it is under pressure of modern and future development. Interestingly, the Urban Heat Island (UHI) phenomenon is prevailed in the area theoretically, but only few studies have been carried out to address the issues in a quantitative manner. Therefore this study aims at providing better insight the UHI phenomenon in Kampung Baru (Kuala Lumpur) and explicitly examines the temperature pattern and its vicinity effect. The field survey will be conducted from December 2014 until March 2015 to collect the temperature and relative humidity within the targeted area. Hence, this survey based on two approaches: mobile and static measurements. The motorcycle equipped with thermo recorder datalogger will be used for mobile survey. While the static measurement using the same type of instrument will be installed at one station in study area with the 1.5 metre height from the ground level. Additionally, climate data from meteorological department will be used for comparison with study area data to estimate the UHI intensity. The data are processed using ArcGIS 10.1 software to portray the temperature pattern at study area. As a result, we developed a smart geo-database of climatic data in such a way it could be used to analyze the spatiotemporal pattern of UHI phenomenon in Kampung Baru, Kuala Lumpur. With a full commitment made by local council, Kampung Baru will be faced a modern and rapid development in 2030. This research provides a baseline data developed in GIS module, which crucial to unveil the spatiotemporal-UHI pattern and reveal climatic pattern in the development area. In conclusion, this study is expected to provide results that are beneficial to the government and urban planning to plan for the new development by taking into account the balance environmental factors in the city of Kuala Lumpur.
URBAN HEAT ISLAND FIRST STATISTICAL ASSESSMENT BASED ON AN MESOSCALE CLIMATOLOGICAL NETWORK IN ARACAJU/BRAZIL
CEG/IGOT University of Lisboa, Portugal
Since 2010, several researches have been developed to study the Urban Heat Island (UHI) of Aracaju, a city located in the northeast of Brazil. The climate is hot and humid and the city has been experiencing an accelerated urban sprawl, which is causing negative effects on the urban canopy layer temperature. This paper shows the first statistical results of the UHI intensity based on an Urban Climatological Network. The mesoscale network was installed in July 2014 and observes principles and concepts defined for urban areas, particularly concerning the climatic scale, sitting and exposure (Local Climate Zones – LCZ), and takes into account the quality assurance and quality control (QA/QC) techniques and metadata. The hourly data (0-23 UTC) of air temperature, relative humidity and absolute humidity of the period from July to September 2014 (end of winter/ beginning of spring) were analysed and compared.
The results reinforce the findings of previous studies, where high UHI frequencies had been found to occur in the city areas that have the highest built up rates (city centre). Nevertheless, the occurrence of the sea breezes is determinant for the UHI configuration. All sites (urban, suburban and rural areas) presented higher frequencies (above of 80%) values between (0°C <ΔT < 2°C) than the site located at the City Park: during the nighttime above 80% and daytime up to 70%. Besides that, in the class range from (2°C <ΔT < 4°C) the frequencies were up to 20% for the two analyzed periods. However, in many cases the sites located further south and close to the coastline (Jose Sarney Beach with 40%, Airport 30%, and Zone Sprawl 20%), negative intensities were observed (-2°C <ΔT < 0°C) due to the influence of sea breezes. During the night and daytime average UHI intensity (up to 2ºC) occurred in more than 80% of the cases and strong UHI (2ºC to 4ºC) occurred in less than 20%.
Most of the observations and the highest mean intensities of UHI occurred between 19:00h pm and 1:00h am. The urban atmosphere remained with the same humidity of 16g/kg as the rural areas during day and nighttime. Nevertheless, the urban effect caused a decrease of 20% in the relative humidity. Results indicate that monitoring the local climate is critical for the urban planning of Aracaju, in view of the negative effects of the UHI on the population, especially considering thermal stress and the increase in energy use.
The Lisbon´s urban heat island patterns, rhythms and relationship with weather types: a decade of hourly temperature data
1CEG/IGOT University of Lisboa, Portugal; 2University of São Paulo, Brazil
Lisbon is located on the western coast of Portugal, about 30km to the east of the Atlantic Ocean, on the right bank of the Tagus River. The complex topography and the vicinity of two water bodies (the ocean to the west and the large estuary to the south and northeast) create very particular climate conditions.
In Lisbon, the wind blows predominantly from the north and northwest all the year, but western, south-western, as well as eastern directions are also frequent. Such a variety of advection flows, in combination with other meteorological variables create several urban heat island patterns that will be investigated in this study.
A mesoscale meteorological network was set up in 2004 by the Centre of Geographical Studies of the University of Lisbon (Climate Change and Environmental Systems research group, former CliMA), in order to understand the influence of the city of Lisbon on the urban heat island effect. Hourly data (from 2004–2014) registered in seven sheltered thermohygrometers across the city (located in spaces with SVF≥0.7), was analysed. For the results presented here the data was divided into night time (20:00 to 6:00 h) and daytime (10:00 to 18:00 h), avoiding thermal anomalies due to shadowing near sunrise and sunset. The main goal of the research is the statistical characterization of Lisbon Urban Heat Island Intensity (UHII).
The first step of the present research consisted in computing temperature deviations from all sites in relations to the airport meteorological station. This procedure was used to find groups of sites with similar thermal behaviour. Four groups were obtained: i) one representing the denser city centre; ii) another one assorting the green park of the city and the outskirts; iii) a third one, the south exposed coastal areas of the city and; iv) the last, representing the more expose to the Tagus estuary eastern part of the city.
The second step consisted in computing the UHII, using the following criteria: in each hour whose temperature in the central city measuring sites (i) was superior to the temperature registered in the peripheral places (ii), one occurrence was considered and the maximum difference was retained. The UHII were classified into “low intensity” (urban-rural differences up to 2°C); “medium intensity” (from 2 to 4°C); “and strong intensity” (> 4 °C). Cool islands were computed when negative differences occurs (same intervals but negative values). Finally the UHII was related with wind speeds and weather types.
Over the last decade a heat island has been observed in Lisbon. During the night, in 50% of cases, the UHI varies from 1.7 to 2.4°C, whereas during the day varies between 1.3 and 2.2°C. The average nocturnal urban heat island was 2°C, while the diurnal only reaches 1.8°C. The maximum UHII observed was 6.1°C during the night and 5.7°C during the day.
During the day, the highest frequency of the UHII (64.7%) occurred in the low intensity class (up to 2°C). During the night the medium intensity class (2 to 4°C) reached the highest frequency (57%). The highest frequencies of UHII took place with winds of 2 to 6 m/s, which differs from the atmospheric calm pattern due to the shelter effect from Northern cold winds. Winds blowing above 8m/s in the Airport area inhibit the occurrence of strong UHI inside the city.
Soil temperature trends in the suburban area of Zagreb
Meteorological and Hydrological Service of Croatia, Croatia
The main goal of this paper is to examine trends in soil temperature for the Zagreb-Maksimir Observatory located in the suburban setting of the city of Zagreb (Croatia). For this purpose monthly and annual mean of soil temeperature data at different depths (2, 5, 10, 20, 30, 50 and 100 cm) as well as other meteorological elements such as air temperature, cloudiness and snow depth for the period (1963-2013) were used. Trends in these soil temperature series were examined using the Mann-Kendall non-parametric test and Sen´s non-parametric method. A positive trend in soil temperatures was detected at all depths and it can be associated with trends in air temperatures and snow cover depth over the same period. A significant decreasing trend in snow cover depth in winter and spring was associated with increasing air temperatures. The combination of two effects, the higher air temperatures and reduced snow depth, probably resulted in an increasing trend in spring and winter soil temperatures.
Estimation of change dynamics of average and extremal annual values of air temperature of air ground layer of Gyumri
Yerevan State University, Armstatehydromet, Armenia
Varduhi Margaryan1, Larisa Simonyan2
1Candidate of geographic sciences, Yerevan State University, Department of Physical Geography and Hydrometeorology, Yerevan, Armenia, Email: email@example.com
2chief of agrometeorology division, Armstatehydromet, Yerevan, Armenia
Air temperature is characteristics of situation on of links of climatic system, athmosphere. It is being determined by features of solar energy distribution on the earth surface, by the processes of interactions between links of climatic system. It is very important the role of air temperature in runoff formation, evaporation, ice events generation and disappearance, thermal and moisture circulation, in frosts, droughts and desertification processes also. The role of thermal regime is also very important in water requirement of agricultural crops and yield formation. So, clarifying and estimation of regularities of temporal distribution of air temperature has importance, especially for more accurate definition of thermal balance, for productive using of thermal resources.
So, the goal of this work was to clarify, analyze and estimate regularities of change dynamics of air temperature in Gyumri city.
For solving this task are collected, clarified and analyzed results of actual observations of air temperature of Gyumri meteorological station, which are being kept in Armstatehydromet. During the studying process are analyzed and clarified appropriate literary sources, are used mathematical-statistical, extrapolation, geographical, analyze and correlation methods.
Have been studied change dynamics of annual average, extremal (absolute maximum and absolute minimum) values of air temperature of Gyumri city. In study area observes a tendency of increase of annual average and extremal values of air temperature.
In the result of study became clear, that features and regularities of spatiotemporal distribution of air temperature depend on complex influence of physical-geographical and anthropogene factors; in perennial observations notes a tendency of increase of annual average and extremal values of air temperature; providing of meteorological stations with modern equipments (especially automatic); inform to population about climate change; realization legal-organization, institutional, technical arrangements for adaptation of economy to new natural conditions and soften of climate change consequences.
Urban Heat Island in Lodz
University of Lodz, Department of Meteorology and Climatology
Lodz, a city with the population of over 700,000, is a sufficiently big settlement and industrial agglomeration for a clearly marked urban heat island to be formed. As a city with a clear urban structure, with the lack of essential vertical differentiation of the terrain and bigger water reservoirs, constitutes a perfect experimental ground for model testing to be performed. The solutions worked out during this process might be successfully applied to the investigation of cities characterized by similar climatic and urban structure traits.
The aims of this work are:
- define the spatial structure and the dynamism of the urban heat island in Lodz,
- asses the intensity and the frequency of the occurrence of the urban heat island, in its diurnal and annual rhythm,
- analyze the genesis of the urban heat island and estimate, in terms of qualitative and quantitative aspects, meteorological and urban structure factors that determine the formation, development and the disappearance of the phenomenon,
- select and define the types of the urban heat island while taking into consideration their diversified genesis, time of the occurrence, durability and the spatial structure.
The accomplishment of the aims of the research work will be based on the genuine meteorological data collected from 14 meteorological stations. Data, with 10 minutes time resolution is collected from January 2014.
Several data study has been already done:
- statistics of the urban heat island intensity in different developments,
- frequency of urban-rural air temperature differences,
- frequency of the urban heat island in different developments,
- mean daily course of air temperature,
- urban-rural air temperature differences,
- cooling rates in different land use types,
- air temperature distribution along specific sections,
- mean daily course of urban-rural air temperature differences,
- mean course of urban-rural air temperature differences with reference to sunset/sunrise,
- frequency of maximal urban heat island intensity during day and night and with reference to sunset and sunrise,
- diurnal cycle of frequency of a given urban-rural air temperature differences,
- diurnal cycle of frequency of negative urban-rural air temperature,
- diurnal cycle of frequency of positive urban-rural air temperature,
- diurnal cycle of frequency of urban-rural air temperature differences greater than 1 K, 3 K,
- mean annual course of urban-rural air temperature differences,
- annual cycle of frequency of a given urban-rural air temperature differences,
- diurnal and annual cycle of urban-rural air temperature differences.
Founding of this research was provided by National Science Center in Poland. Grant number: 2012/05/B/ST10/00945.
Long-term Dynamics of the Urban ‘Heat Island’ in Moscow
Lomonosov Moscow State University, Faculty of Geography, Russian Federation
The urban ‘heat island’ in Moscow city has been investigated for the period since 1880s till nowadays using the data of the ground meteorological network. Besides a traditional intensity of the UHI (i.e. averaged in time difference between the air temperature in the city centre and outside the city) an additional parameter – so-called ‘areal’ UHI intensity – has been suggested. It represents a value averaged both in time and in space (a difference between mean air temperature in the city area and outside the city). As it is shown a mean usual intensity of the urban ‘heat island’ in Moscow was nearly of 1.0-1.2 ºC at the end of the 19th century, 1.2-1.4 ºC one century ago and 1.6-1.8 ºC both in the middle, and at the end of the 20th century whereas the ‘areal intensity’ was equal to 0.8-0.9 ºC both in the middle, and at the end of the 20th century. Thus, during several last decades both parameters remained nearly the same in spite of continued growth of the city. The probable explanation is that the urban growth seems to be extensive now so that the urban saturation and density of heat sources in the centre of the city changed only a bit during the last half of the century.
In the diurnal course the ‘heat island’ intensity in Moscow is maximal usually at night. The maximal ‘heat island’ intensity in Moscow may reach up to 14 ºC, usually at night or in the early morning.
Weekly course of the air temperature in Moscow has been studied additionally because it is closely connected with the urban ‘heat island’ phenomenon. On the average during the last 50 years there was a gradual increase of T during week-days and sharp decrease (cooling) on weekends. This may be explained by industrial haze which is gradually accumulated from Monday to Friday and reduces effective nocturnal radiation in the city, especially during winter nights.
Some general information about climate of Moscow and current tendency of its change will be given at the report as well.
Wind Condition Changing in Tomsk at the Beginning of XXI Century: Ecological Aspect
National Research Tomsk State University, Russian Federation
The wind is considered to be one of the most significant characteristics of atmosphere. It is determined by circulation, pressure gradient, temperature condition, as well as, meso- and microclimatic peculiarities.
Living conditions in a city of Tomsk are affected by winds. The stormy wind exerts loads on the buildings, causing cooling especially at low temperature, which is typical of Siberia. Ecological conditions in the city and its adjacent areas are governed by the wind and other climatic factors.
Tomsk is a scientific and industrial centre where one can find power industry, oil and gas industry, chemical industry. Machinery-producing industry and constructional materials production are also developed. For the efficient work of industrial enterprises, transport, register of air composition changes and healthy living conditions the information on the wind and its directions for a long term period is of great importance.
This paper deals with the main wind characteristics of the beginning of the XXI century according to the standard observations at the Tomsk weather service station and weather observations, which are carried out in the Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science (observations at the TOR-station, the north-eastern part of Tomsk). Estimation has been made of climatic changes in the velocity and direction of winds since 1936.
Based on the observations, the following conclusions for Tomsk and its adjacent areas were made:
1) the significant decrease in average wind velocity and the number of days with stormy wind are common for a long term period;
2) the increase in frequency of no wind periods (stills);
3) the dominant wind direction has not changed and remained southern, south-western and western winds frequency being increased. Southern wind frequency is gradually increasing.
In this paper, the characteristics of low winds are considered.
Climatic characteristic changing, when the wind velocity decreases, contributes to pollution getting worse in the last decades.
Observations of the concentration of the main atmospheric contaminants are made at 6 observation points as well as at the TOR-station in Tomsk. It is found out that in recent years the average annual concentrations of NO, NO₂, HCL, dust has been increasing not so much, though.
However, special features of industrial production, growth of automobiles play the main role in polluting air with dangerous substances. Using gas and fuel oil at the heating enterprises and introducing nitrogen oxide control have resulted in the significant decrease of SO₂, CO, ammonia, phenol. Currently, NO₂, HCL, dust meet MAC indices in the air, but formaldehyde exceeds them.
Redistribution of the amounts of emissions between industries and vehicles has occurred recently: vehicles, the number of which has significantly increased, play a major role in air pollution.
Hence, the ecological situation in Tomsk is quite favorable as compared to other Siberian cities.
1. Arshinova V.V., Belan B.D., Zuev V.V. et al. The TOR-station of Atmospheric Parameters Monitoring. Optics of Atmosphere and Oceans. 1994. V. 7. №8
2. Ahmetshina A., Zhuravlev G., Romaniuk V. Monitoring of air pollution in the city of Tomsk. – Bulletin of the TSU, 2009. №328. S. 208-213.
This work was performed by order of the Ministry for education and science of the Russian Federation No. 5.628.2014/K.
Urban and Rural Temperature Trends in Proximity to Large US Cities: 1973-2013
Georgia Institute of Technology Urban Climate Lab, United States of America
This paper presents an ongoing study of urban and rural temperature trends in proximity to the most populous metropolitan areas of the US. As data from urban meteorological stations are typically eliminated or adjusted for use in continental and global analyses of climate change, few studies have addressed how temperatures are changing in the areas most vulnerable to the public health impacts of warming: large cities. In this study, temperature data from urban and proximate rural stations for 62 large US metropolitan areas are analyzed to establish the mean decadal rate of change in urban temperatures, rural temperatures, and heat island intensity over five decades. The results of our previous analysis covering the period 1951-2000 found the mean decadal rate of change in the heat island intensity of large US cities to be 0.05 C and further showed a clear division in temperature trends between cities situated in the northeastern and southern regions of the country.
THE ASSESSMENT OF THERMAL AIR CONDITION IN TOMSK AND THE TRENDS IN ANTICYCLOGENESIS IN SIBERIA
Tomsk State University, Russian Federation
In this study the assessments of changing meteorological and calculated temperature parameters of surface air which are known to feature present climatic conditions over the territory of Tomsk are given. The tendencies of anticyclogenesis over Siberia and its potential effect on the thermal condition are shown. The mean values of daily air temperatures above the defined ranges (0, 5, 10 and 15 °С), the duration of extreme air temperature periods (≥ 30 и 35 °С, ≤ –25, –30, –35 and –40 °С), belonging to the dangerous weather events (DWE), absolute extremes of air temperature, as well as their probable marketable features (with 92, 95 and 98 % occurrence) are established. The study of long – term air temperature trends for the last 40 years revealed the temperature growth up to 0.5 ºС every 10 years, the trends in February reaching 1.6 ºС every 10 years whereas the temperature did not change in April, September and November. Temperature risks associated with such dangerous weather events as high – low temperature periods, abnormally cold – abnormally hot weather, severe cold – heatwave, also were considered. Dangerous events associated with low temperatures were found to predominate in Tomsk and what is more, they are long – term. It was shown that the dangerous event “heat wave” is not typical of Tomsk. Activation of blocking the zonal transport in atmosphere gave rise to the increased frequency of dangerous events either with extremely low or with extremely high temperatures in those years.