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1.
利用新一代中尺度研究和预报模式(Weather Research and Forecasting Model,简称WRF)分别耦合多冠层、单冠层和平板模式三种情况进行南京地区2007年8月1日的天气过程模拟,分析不同城市冠层方案对南京气象场的模拟效果。在此基础上,结合模拟效果最好的城市冠层方案,研究南京城市下垫面的变化对其热岛的影响。结果表明:多冠层方案对近地面气温、10 m风场的模拟效果最好;城区的扩张使南京地区近地面气温升高,主要表现为城市区域夜间升温显著,并且导致热岛强度明显增强;城市扩张后,城区白天风速大范围地减小,同时热岛环流更加显著,且具有明显的城市热岛的"下游效应"。 相似文献
2.
The study underlines the characteristics of the urban heat island of Ia?i (Ia?i’s UHI) on the basis of 3 years of air temperature measurements obtained by fixed-point observations. We focus on the identification of UHI development and intensity as it is expressed by the temperature differences between the city centre and the rural surroundings. Annual, seasonal and daily characteristics of Ia?i’s UHI are investigated at the level of the classical weather observation. In brief, an intensity of 0.8 °C of UHI and a spatial extension which corresponds to the densely built area of the city were delineated. The Ia?i UHI is stronger during summer calm nights—when the inner city is warmer with 2.5–3 °C than the surroundings—and is weaker during windy spring days. The specific features of Ia?i’s UHI bear a profound connection to the specificity of the urban structure, the high atmospheric stability in the region and the local topography. Also, the effects of Ia?i’s UHI upon some environmental aspects are presented as study cases. For instance, under the direct influence of UHI, we have observed that in the city centre, the apricot tree blossoms earlier (with up to 4 days) and the depth of the snow cover is significantly lower (with up to 10 cm for a rural snow depth of 30 cm) than in the surrounding areas. 相似文献
3.
Urban Heat Island and Boundary Layer Structures under Hot Weather Synoptic Conditions: A Case Study of Suzhou City, China 总被引：3，自引：0，他引：3
A strong urban heat island (UHI) appeared in a hot weather episode in Suzhou City during the period from 25 July to 1 August 2007. This paper analyzes the urban heat island characteristics of Suzhou City under this hot weather episode. Both meteorological station observations and MODIS satellite observations show a strong urban heat island in this area. The maximum UHI intensity in this hot weather episode is 2.2℃, which is much greater than the summer average of 1.0℃ in this year and the 37-year (from 1970 to 2006) average of 0.35℃. The Weather Research and Forecasting (WRF) model simulation results demonstrate that the rapid urbanization processes in this area will enhance the UHI in intensity, horizontal distribution, and vertical extension. The UHI spatial distribution expands as the urban size increases. The vertical extension of UHI in the afternoon increases about 50 m higher under the year 2006 urban land cover than that under the 1986 urban land cover. The conversion from rural land use to urban land type also strengthens the local lake-land breeze circulations in this area and modifies the vertical wind speed field. 相似文献
4.
Admir Créso Targino Patricia Krecl Guilherme Conor Coraiola 《Theoretical and Applied Climatology》2014,117(1-2):73-87
Air temperature was monitored at 13 sites across the urban perimeter of a Brazilian midsize city in winter 2011. In this study, we show that the urban heat island (UHI) develops only at night and under certain weather conditions, and its intensity depends not only on the site's land cover but also on the meteorological setting. The urban heat island intensity was largest (6.6 °C) under lingering high-pressure conditions, milder (3.0 °C) under cold anticyclones and almost vanished (1.0 °C) during the passage of cold fronts. The cooling rates were calculated to monitor the growth and decay of the UHI over each specific synoptic setting. Over four contiguous days under the effect of a lingering high-pressure event, we observed that the onset of cooling was always at about 2 h before sunset. The reference site attained mean cooling rate of ?2.6 °C h?1 at sunset, whilst the maximum urban rate was ?1.2 °C h?1. Under a 3-day cold anticyclone episode, cooling also started about 2 h before sunset, and the difference between maximum rural (?2.0 °C h?1) and urban (?1.0 °C h?1) cooling rates diminished. Under cold-front conditions, the cooling rate was homogeneous for all sites and swang about zero throughout the day. The air temperature has a memory effect under lingering high-pressure conditions which intensified the UHI, in addition to the larger heat storage in the urban area. Cold anticyclone conditions promoted the development of the UHI; however, the cold air pool and relatively light winds smoothed out its intensity. Under the influence of cold fronts, the urban fabric had little effect on the city's air temperature field, and the UHI was imperceptible. 相似文献
5.
Summary This paper examines the characteristics of the morning Urban Heat Island (UHI) in Athens basin, Greece. The study is performed
by using and analyzing mesoscale and synoptic data covering the period 1990–2001. The UHI was estimated using the 0600 Local
Time (LT) minimum temperature differences between rural and urban areas of the city. The analysis results in 7 UHI classes.
A strong UHI was found for the 1/3 of days. The specific meteorological characteristics (surface and upper air, cooling rate)
of each UHI class were revealed and examined. The spatial and temporal characteristics of the UHI were also identified.
The UHI is largest on nights with clear skies and low relative humidity. In all seasons the UHI switches on rapidly in afternoon.
During spring and summer, sea breeze commonly reduces and delays the UHI. Cases documenting the sensitivity and rapidity of
changes of the UHI to changes in classes (cloud cover, wind) are also presented. The cooling rate is higher in the urban area
under negative and lower under positive UHI conditions.
Mesoscale and macroscale phenomena were examined during the different UHI classes through a weather type scheme. It was emerged
that high UHI classes are associated with anticyclonic conditions or advection in the lower troposphere, while low UHI classes
are associated with strong northeasterly winds. Anticyclonic conditions which frequently occur in spring and early summer,
reduce or reverse the UHI to Urban Cooling Island. 相似文献
6.
Summary This study presents the results of a preliminary research that was conducted in the city of Eilat, located in an extreme hot
and arid zone on the northern coast of the Red Sea. The purpose was to analyse the characteristics of the local urban heat
island (UHI). Diurnal pre-dawn and early-afternoon measurements were taken in winter and summer weather conditions on three
separate occasions for two consecutive years. The results show the development of a moderate UHI located around the most intensive
area of human activity; the city business centre and dense hotel belt. The UHI is more significant at midday during the summer
period, while early morning inversions in winter have a weakening effect on the UHI intensity. It was found that the topography
and wind regime have a dominant effect on the location and intensity of the UHI, while the sea has a very marginal effect.
Due to the UHI influences on the spatial distribution of the heat stress in the city, it is suggested that further applied
UHI research should be focused on the summer period. 相似文献
7.
Manju Mohan Yukihiro Kikegawa B. R. Gurjar Shweta Bhati Narendra Reddy Kolli 《Theoretical and Applied Climatology》2013,112(3-4):647-658
Urban heat island intensities (UHI) have been assessed based on in situ measurements and satellite-derived observations for the megacity Delhi during a selected period in March 2010. A network of micrometeorological observational stations was set up across the city. Site selection for stations was based on dominant land use–land cover (LULC) classification. Observed UHI intensities could be classified into high, medium and low categories which overall correlated well with the LULC categories viz. dense built-up, medium dense built-up and green/open areas, respectively. Dense urban areas and highly commercial areas were observed to have highest UHI with maximum hourly magnitude peaking up to 10.7 °C and average daily maximum UHI reaching 8.3 °C. UHI obtained in the study was also compared with satellite-derived land surface temperatures (LST). UHI based on in situ ambient temperatures and satellite-derived land surface temperatures show reasonable comparison during nighttime in terms of UHI magnitude and hotspots. However, the relation was found to be poor during daytime. Further, MODIS-derived LSTs showed overestimation during daytime and underestimation during nighttime when compared with in situ skin temperature measurements. Impact of LULC was also reflected in the difference between ambient temperature and skin temperature at the observation stations as built-up canopies reported largest gradient between air and skin temperature. Also, a comparison of intra-city spatial temperature variations based UHI vis-à-vis a reference rural site temperature-based UHI indicated that UHI can be computed with respect to the station measuring lowest temperature within the urban area in the absence of a reference station in the rural area close to the study area. Comparison with maximum and average UHI of other cities of the world revealed that UHI in Delhi is comparable to other major cities of the world such as London, Tokyo and Beijing and calls for mitigation action plans. 相似文献
8.
Large-scale atmospheric circulations associated with 133 moderate to heavy cold-weather precipitation events recorded at Mehrabad station in Tehran, Iran, during the period 1951–2013 are analysed. To this end, the performance of un-rotated, orthogonally rotated and obliquely rotated solutions of T-mode principal component analysis (PCA) is examined in classifying the atmospheric circulations into a few representative circulation types (CTs). The T-mode PCAs were applied to the 500-hPa geopotential height for the events in a domain from 10°E to 70°E and from 20°N to 50°N. The first six leading principal components were retained and then orthogonally and obliquely rotated using varimax and promax solutions, respectively. Statistical inter-comparison of the CTs obtained using the three solutions suggests that the obliquely rotated solution is the better choice for circulation classification in the present study. The six CTs obtained using the oblique rotation were then linked to the daily total precipitation and daily mean temperature variability at Tehran station as well as to the standardized anomalies of the daily total precipitation and mean daily temperature of a dense network of stations distributed across Iran. It is found that the CTs identified, though generally comparable in producing significant precipitation in Tehran, vary in their potential to bring cold weather and generate snowfall in Tehran specifically and in the country in general. While the first three CTs give rise to regional patterns of standardized precipitation anomalies centred in Tehran, the next three CTs leave a pronounced precipitation signature almost across the whole country. As regards the standardized temperature anomalies, with the exception of one CT that causes deep and widespread negative standardized anomalies over most parts of the country, the other CTs are characterized with a dipolar structure of a deep intrusion of cold weather to the west and prevailing warm weather to the east of the country. 相似文献
9.
不同天气条件下沈阳城市热岛特征 总被引：5，自引：0，他引：5
利用1992—2008年沈阳站和新城子站逐日4个时次的平均气温、平均风速、降水量、云量和能见度资料,对不同天气条件下沈阳的城市热岛效应进行研究。结果表明：除雾和浓雾天气条件下,沈阳城市热岛强度在08时最弱外,其他天气条件下均表现为20时最强,14时最弱;不同天气条件下,夜间城市热岛强度均高于白天;晴朗无风条件下昼夜城市热岛强度差最大,为0.73℃。四季相比,除雾条件下秋季城市热岛强度最强外,其他天气条件下均为冬季最强;除大雨条件下春季城市热岛强度最弱外,其他条件下均为夏季最弱。沈阳城市热岛强度随降水量的增加而减弱,随能见度的降低而减弱,随着风速的增加而减弱。白天和夜间两个时次的差值表现为,1～3级风夜间变化幅度大于白天,0级和4～5级风速有相反规律,其他天气条件下无明显规律。 相似文献
10.
近15年北京夏季城市热岛特征及其演变 总被引：5，自引：1，他引：5
根据北京地区20个地面气象观测台站1990-2004年7月的气温资料，分析了最近15年来北京夏季城市热岛的最新特征和变化趋势，也分析了城市热岛与气温，城郊地表温度差与地表温度，气温和地表温度间的关系。结果表明：北京夏季夜间出现了强热岛，郊区城市也出现了热岛现象，但白天城市热岛相对夜间不明显。夜间城市热岛强度呈逐年增强趋势，但白天这种趋势不明显。夜间城市热岛与气温呈正相关，气温高的年份，城市热岛强度相对也大；夜间城郊地表温差与地表温度呈正相关，地表温度越高，城郊地表温差越大；夜间，气温与地表温度呈正相关，气温越高，地表温度也高。白天，这些相关相对夜间来说不那么明显。研究成果对北京城市发展规划和高温灾害的防治有一定的科学参考价值。 相似文献
11.
Temporal characteristics of the Beijing urban heat island 总被引：4，自引：0，他引：4
Summary This paper describes the inter-annual trend, and the seasonal and hourly variation of the near surface urban heat island (UHI)
in Beijing. The surface air temperature data (mean, maximum, and minimum) from one urban (downtown Beijing) and one rural
(70 km from downtown Beijing) station were used for the period 1977 and 2000. It is found that the temperatures in both urban
and rural stations show an increasing tendency. Specifically, minimum temperature shows the greatest tendency at the urban
station whereas maximum temperature shows the greatest increase at the rural station. The UHI intensity obtained by calculating
the difference in temperatures between the two stations identifies that the intensity is greatest and has the greatest increasing
trend for minimum temperature, while the UHI intensity of maximum temperature shows a slow decrease over time. UHI intensity
for minimum temperature has a strong positive correlation with the increase in the urban population and the expansion of the
yearly construction area. Seasonal analyses showed the UHI intensity is strongest in winter. This seasonal UHI variation tends
to be negatively correlated with the seasonal variation of relative humidity and vapor pressure. Hourly variation reveals
that the strongest UHI intensity is observed in the late nighttime or evening, while the weakest is observed during the day. 相似文献
12.
北京夏季强热岛分析及数值模拟研究 总被引：5，自引：1，他引：5
应用北京地区20个常规地面气象站、2个自动气象站和中国科学院大气物理研究所325m气象铁塔的资料，对北京2003年7月热岛状况进行了统计分析，发现北京夏季夜间存在强热岛效应，夏季夜间存在强热岛效应的天数占到了1/3，强弱热岛天数合计占到了大约4/5。进一步分析7月1日强热岛特征及其气象影响因子，结果表明：夜间存在强热岛时，郊区所有测站的地面气温都要低于主城区地面气温，城市强热岛的高温中心在天安门和白家庄连线的主城区；白天日照充足的晴夜，日落后城区320m以下低层大气存在逆温和弱的风速，城区地面气温下降速率和幅度均远小于郊区，城市强热岛因此得以形成和维持。日出后至正午，北京北部郊区日照时间比城区长，郊区地面大气得到来自太阳辐射的能量多于城区，而太阳辐射的加热作用使城区低层大气逆温消失，大气稳定度减弱，并使郊区地面气温上升速率和幅度大于城区，最终导致夜间出现的强热岛减弱、消失。此外，应用MM5模式对强热岛进行了初步数值模拟研究，发现在MM5中考虑城市人为热和热储存，可以改善模式对热岛的数值模拟，表明城市人为热和热储存在夏季强热岛的形成中有重要作用。 相似文献
13.
The urban heat island (UHI) of the city of Bucharest (Romania) is analyzed in terms of its extension, geometry, and magnitude using the surface thermal data provided by the moderate resolution imaging spectroradiometer (MODIS) sensors. An objective method is developed that allows to delineate the UHI. The study focuses on the months of July from the 2000–2006 time interval. The average surface temperatures obtained for each pixel (1 km resolution) were analyzed on cross-profiles that helped us to determine the outline of the UHI. The shifting points identified by the Rodionov test in the temperature series of each profile were considered as possible limits of the UHI. Seemingly, the land cover has a major influence on the extension and the geometry of the Bucharest UHI in July. The magnitude of the heat island was calculated by comparing the average temperature inside its limits and the average temperature of the 5 km (a) and of the 10 km (b) buffers around it. The thermal difference between the UHI and the surrounding area of Bucharest is higher and more variable during the daytime, and is noticeably related to the land cover. 相似文献
14.
The sensitivity of the sea-surface temperature (SST) prediction skill to the atmospheric internal variability (weather noise) in the North Pacific (20°–60°N;120°E–80°W) on decadal timescales is examined using state-of-the-art Climate Forecasting System model version 2 (CFS) and a variation of CFS in an Interactive Ensemble approach (CFSIE), wherein six copies of atmospheric components with different perturbed initial states of CFS are coupled with the same ocean model by exchanging heat, momentum and fresh water fluxes dynamically at the air-sea interface throughout the model integrations. The CFSIE experiments are designed to reduce weather noise and using a few ten-year long forecasts this study shows that reduction in weather noise leads to lower SST forecast skill. To understand the pathways that cause the reduced SST prediction skill, two twenty-year long forecasts produced with CFS and CFSIE for 1980-2000 are analyzed for the ocean subsurface characteristics that influence SST due to the reduction in weather noise in the North Pacific. The heat budget analysis in the oceanic mixed layer across the North Pacific reveals that weather noise significantly impacts the heat transport in the oceanic mixed layer. In the CFSIE forecasts, the reduced weather noise leads to increased variations in heat content due to shallower mixed layer, diminished heat storage and enhanced horizontal heat advection. The enhancement of the heat advection spans from the active Kuroshio regions of the east coast of Japan to the west coast of continental United States and significantly diffuses the basin-wide SST anomaly (SSTA) contrasts and leads to reduction in the SST prediction skill in decadal forecasts. 相似文献
15.
Summary ¶Re-analysed data from an urban climate research project in Munich, Germany, were used to investigate the spatio-temporal variability of moisture conditions (expressed here in vapour pressure VP) within the Urban Canopy Layer UCL. The results, which apply to three main sites and additional subsidiary ones, cover both summer and winter months. The summer month variation of VP is characterised by higher monthly mean values of VP for all three sites, howbeit with considerable inter-site differences. The temporal variability of mean VP values at diurnal time scales is also examined. With respect to the UCL, they reveal different amplitudes and times of occurrence of their extreme values. In addition, results of car traverses performed during clear sky conditions in downtown Munich show a remarkable small-scale spatio-temporal variability of VP.In relation to a sealed downtown site within a courtyard in Munich, a time-dependent urban moisture excess (UME) was formed. A positive correlation between UME and the urban heat island (UHI) could be verified in general. However, it was slightly negative with a very low coefficient of determination in the summer month when the maximum UME preceded the maximum UHI up to 5hrs. As example for the effects of air moisture on the urban climate within the UCL, the role of VP on a thermal index (physiologically equivalent temperature PET) was investigated. Based on one-year data from another urban climate project in Munich, a positive correlation between PET and VP was found, although the coefficient of determination was somewhat low. However, during a human-biometeorological case study on a typical summer day in the northern downtown of Freiburg, a medium-sized city in southwest Germany, PET and VP showed a negative correlation (possibly because the specific temporal course of VP at the measuring points was mainly influenced by thermally induced turbulence). 相似文献
16.
Summary ?During recent years, numerous studies have examined the Buenos Aires urban climate, but the relationship between large-scale
weather conditions and the Buenos Aires urban heat island (UHI) intensity has not been studied. The goal of this paper is
to apply an objective synoptic climatological method to identify homogeneous air masses or weather types affecting Buenos
Aires during winter, and to relate the results to the UHI intensity. A K-means clustering method was used to define six different
air masses considering the 03:00, 09:00, 15:00 and 21:00 LT surface observations of dry bulb temperature, dew point, cloud
cover, atmospheric pressure and wind direction and velocity at Ezeiza, the most rural meteorological station of the Buenos
Aires metropolitan area (Fig. 1). Results show that the mean UHI intensity is at its maximum (2.8 °C) a few hours before sunrise
when conditions are dominated by cold air masses associated with cold-core anticyclones, weak winds and low cloud cover. Inverse
heat islands are found during the afternoon for all air masses indicating that surface processes are not dominant at that
time. The relatively infrequent and warmest air mass is the only one that presents a mean negative urban-rural temperature
difference (−0.1 °C) during the afternoon with the smallest diurnal cycle of the UHI intensity probably due to the prevailing
high humidity and cloudy sky conditions. The paper provides an insight into the Buenos Aires urban–rural temperature difference
under a variety of winter weather types and results could be useful to improve local daily temperature forecasts for the metropolitan
area of Buenos Aires on the basis of the routine forecasts of weather types.
Received October 24, 2001; revised June 12, 2002; accepted October 10, 2002 相似文献
17.
利用MODIS地表温度数据,计算城市热岛强度指数,分析近15年广州市城市热岛的时空分布特征及演变规律,并结合气象观测数据、社会统计数据定性分析其主要影响因素。结果表明:广州市城市热岛的空间分布受地形地貌影响明显,负热岛区主要分布于森林密集的北部山区,无热岛区主要分布于中部低山丘陵区域,热岛区主要分布于高度城市化的中南部平原区。关于城市热岛的日变化规律,白天热岛区、负热岛区面积均小于夜间,但白天热岛区强度、负热岛区强度大于夜间。关于城市热岛的季节变化规律,冬季热岛区面积最大,热岛强度最小,夏季热岛区面积最小,热岛强度最大;冬季负热岛区面积最小,负热岛强度最小,夏季负热岛区面积最大,负热岛强度最大。对于城市热岛的年际变化规律,近15年来广州市的热岛区、负热岛区占全市总面积的百分比呈上升趋势,无热岛区所占百分比呈下降趋势,人为热排放在城市中心区域的持续增长,加上区内建筑物密度大、植被覆盖度低,导致了热岛区的增加,而北部山区至中部丘陵山区的植被的持续好转,加上地理特征限制了该区域的城市化发展,导致了负热岛区的增加。 相似文献
18.
利用1972－2011年阳泉市3个国家级气象站资料、2011年36个乡镇区域自动站气温资料,分析了阳泉市城市热岛效应的年际变化、季节变化、月变化和日变化特征。结果表明：阳泉市存在弱的城市热岛效应,1972－2011年平均热岛强度0.554 ℃。阳泉市城市热岛强度整体呈显著上升趋势,热岛强度的增加主要是由于夏季热岛强度的增强;热岛强度冬、秋季强,春、夏季弱;12月最强,5月最弱;热岛强度日变化表现为12时最小,从傍晚开始随降温逐渐增大,到早晨气温降到最低时最大,日出之后迅速减小;2008－2011年最强热岛强度出现在2010年1月14日08时,达7.9 ℃。阳泉在升温天气热岛强度变幅增大,易在早晨形成较强城市热岛,下午形成城市冷岛;降温天气热岛强度变幅减小;温度变化较小时则易维持弱的城市热岛。阳泉市主要城市发展因子与霾日数、气温呈显著正相关,在目前的经济发展水平条件下,阳泉市城市化发展可能使城市温度增高,城市绿地面积的增加可能对热岛效应有缓解作用。 相似文献
19.
I. González-Aparicio J. Hidalgo A. Baklanov U. Korsholm R. Nuterman A. Mahura O. Santa-Coloma 《Theoretical and Applied Climatology》2013,113(3-4):511-527
This study analyses the atmospheric boundary layer over the Bilbao metropolitan area during summer (13–18 Jul 2009) and winter (20–29 Jan 2010) episodes using the Environment–High Resolution Limited Area Model (Enviro-HIRLAM) coupled with the building effect parameterisation (BEP). The main objectives of this study are: to evaluate the performance of the model to simulate the land–sea breezes over this complex terrain; to assess the simulations with the integration of an urban parameterisation in Enviro-HIRLAM and finally; and to analyse the urban–atmosphere interactions. Even if the hydrostraticity of the model is a limitation to simulate atmospheric flows over complex terrain, sensibility tests demonstrate that 2.4 km is the optimal horizontal resolution over Bilbao that allows at the same time: to obtain satisfactory reproducibility of the large-scale processes and to explore the urban effects at local scale. During the summer episode, a typical regime of diurnal sea breeze from the NW-N-NE direction and nocturnal valley breezes from the SE direction are observed over Bilbao. The urban heat island (UHI) phenomenon is developed in the city centre expanding to the suburbs from 22 to 10 local time (LT), covering an area of 130 km2. The maximum UHI intensity, 1 °C, is reached at the end of the night (5 LT), and it is advected 12 km towards the sea by the land breezes. The urban boundary layer (UBL) height amplitude varies from 100 (night time) to 1,360 m (at 14 LT). During the winter episode, the land breeze dominates the atmospheric diffusion during the day and night time. The maximum UHI intensity, 1.7 °C, is observed at 01 LT. It is spread and remained over the city covering an area of 160 km2, with a vertical extension of 33 m. The UBL reaches 780 m height at 16 LT the following day. 相似文献
20.
Edmilson D. Freitas Christopher M. Rozoff William R. Cotton Pedro L. Silva Dias 《Boundary-Layer Meteorology》2007,122(1):43-65
The Town Energy Budget (TEB) model, a detailed urban parameterisation using a generalised canyon geometry, coupled with the
Regional Atmospheric Modelling System (RAMS) is used to simulate the wintertime local circulation in the megacity environment
of the metropolitan area of Sao Paulo (MASP) in Brazil. Model simulations are performed using actual topography and land-use
fields. Comparison with a simple urban parameterisation based on the LEAF-2 scheme is also shown. Validation is based on comparison
between model simulations and observations. Sensitivity tests with TEB reveal an important interaction between the sea breeze
and the MASP heat island circulation. Even though topography is known to play an important role in the MASP region’s weather,
in these tests the simulations were performed without topography in order to unambiguously identify the interaction between
the two local circulations. The urban heat island (UHI) forms a strong convergence zone in the centre of the city and thereby
accelerates the sea-breeze front toward the centre of the city. The presence of the urban region increases the sea-breeze
front propagation mean speed by about 0.32 m s−1 when compared with the situation of no city. After its arrival in the urban region, the sea-breeze front stalls over the
centre of the city for about 2 h. Subsequently, the sea breeze progresses beyond the city when the heat island dissipates.
Thereafter, the sea breeze propagates beyond the urban area at a decelerated rate compared to a simulation without an UHI. 相似文献