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1.
Heat island is a very well documented climatic phenomenon that has an important energy and environmental impact in the urban
environment. The main energy problems are related to the important increase of the energy consumption for cooling purposes
as well as to the important increase of the peak electricity load. Heat island in Athens, Greece, is measured during the last
decade and its energy impact is calculated in details. The aim of the present paper is to estimate the direct and indirect
environmental impact of the heat island effect in Athens. This is achieved through the estimation of the additional ecological
footprint caused by the urban heat island phenomenon over the city. The ecological footprint estimation is performed at a
first step by calculating the increase of the cooling demand caused by the heat island over the whole city and then by translating
the energy to environmental cost. Two years annual experimental data from many urban stations have been used. The results
show that the ecological footprint because of the heat island ranges 1.5–2 times the city’s political area that have to be
reserved every year to compensate the additional CO2 emissions caused by the presence of the heat island effect while the maximum potential ecological footprint, provided that
all buildings are air conditioned, is almost 110,000 hectares. 相似文献
2.
Climate Variability and Urbanization in Athens 总被引:2,自引:0,他引:2
Summary The effects of urbanization on the Athens National Observatory (NOA) long records are investigated, in the present study,
examining the mean monthly maximum and minimum air temperature for the period 1925–1996, for NOA and the corresponding time
series for Aliartos (ALI), a rural station located 70 km NW of Athens. The existing small urbanization effect in NOA before
the second world war period increased after the war and up to about 1990, when the effect became stationary. The urbanization
effect in NOA referred mainly to maximum temperature and to the warmer seasons of the year. It is attributed to the extensive
building of Athens after the war around NOA site and up to the sea which increases the temperature of the sea breeze. The
effect is also attributed to the rapid increase of the population and the number of motor vehicles mainly after 1970. Moreover
the decreasing trend of precipitation during the period 1970–1990 may have contributed to the increase of maximum air temperature.
The urbanization effect on maximum temperatures of NOA amounts about 2 °C in spring, summer and less in fall, while no urbanization
effect is clear in winter.
Received March 25, 1998 Revised October 7, 1998 相似文献
3.
金丽娜 《沙漠与绿洲气象(新疆气象)》2021,15(1):97-102
选取1971—2017年7个国家级气象站的气温资料,分析年代际气温变化特征及城郊温差、城县温差;选取2014—2017年103个国家考核区域气象站及7个国家级气象站逐时气温资料,利用标准化相对气温法,研究西安市城市热岛、冷岛的年、季平均空间分布特征,以及逐日热岛、冷岛变化规律。结果显示:1971—2017年城区、郊区和郊县气温均呈上升趋势,城区增温速率最大,郊县增温速率最小,进入21世纪后,城市热岛效应较为显著。西安市城市热岛、冷岛现象明显,且均呈"多中心"特征,热岛中心多为老城区及旅游中心,建筑物面积和人口密度占绝对优势;冷岛中心多为地势较高、水域绿被覆盖较大、非人口密集区的秦岭坡脚线附近。城区代表站的年、春季、夏季、秋季基本处于平稳状态,年、春季、夏季06—07时热岛强度最大,秋季、冬季23时热岛强度最大;郊区代表站和郊县代表站的年及四季热岛、冷岛强度均有明显的日变化特征,且变化趋势相反;郊区代表站10时热岛转为冷岛,春、夏季16—17时转为热岛,年及秋、冬两季19—20时转为热岛;郊县代表站年、春季、夏季06—07时冷岛强度最大,秋季、冬季2时冷岛强度最大,08时后冷岛开始减弱,12—13时为最弱后开始增强。 相似文献
4.
In the present study, we examine the dynamics of a sea-breeze front and the urban heat island interacting with the heavily
urbanized city of Athens. For this reason, simulations were performed with a modified version of the PSU/NCAR Mesoscale Model
(MM5), whereby urban features are considered, and the model results were compared with surface routine meteorological data.
An unrealistic run was also performed, where the city of Athens was replaced by dry cropland and pasture surface, as in the
surrounding area. A delay in the sea-breeze front was found during daytime, together with frictional retardation concerning
its penetration, as well as inland displacement of the heat island as the air moved over the city of Athens. During nighttime,
the wind speed increased over the lower atmosphere in the city centre due to the enhanced urban heat island. 相似文献
5.
Juan A. Acero Jon Arrizabalaga Sebastian Kupski Lutz Katzschner 《Theoretical and Applied Climatology》2013,113(1-2):137-154
This work examines the characteristics of the urban heat island (UHI) in a medium-sized city in northern Spain (Bilbao) using 5-year climate data (2005–2009) and the results of three specific measurement campaigns (2009–2010). Urban climate variables are not only compared with those in rural sites but also local climatic differences occurring inside the city are analysed. The findings presented in this paper show the influence of complex topography and sea/land breeze in the urban climate. Spatial characteristics and temporal evolution of UHI is presented. Hourly maximum temperature anomaly (ΔT u–r, max) occurs just after sunrise and an urban cold island (UCI) is developed after midday. Along the year, mean UHI intensity is highest in autumn and the UCI effect increases in spring and summer in relation with sea breeze cooling potential. Diurnal and seasonal variation of air flow patterns appear to influence significantly on UHI intensity. 相似文献
6.
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
7.
H. Wanner C. Pfister R. Brázdil P. Frich K. Frydendahl T. Jónsson J. Kington H. H. Lamb S. Rosenørn E. Wishman 《Theoretical and Applied Climatology》1995,51(3):167-175
Summary The North Atlantic and Western Europe regions comprise a key area to study climate variations in the form of cold relapses which may be a possible manifestation of reduced ocean circulation. By using multi-proxy data of the late Maunder Minimum period, temperature and precipitation distribution during winter was studied in connection with atmospheric circulation, with the goal of obtaining an insight into the feedbacks between ocean, sea ice and temperature. The study shows that the Late Maunder Minimum was a relatively cool and dry period with low ocean temperatures and a large sea ice extent, although Alpine glaciers did not grow during this time. A comparison of the winter weather types of the three decades from 1675 to 1704 with the recent 30 year period (1961–1990) shows that the late Maunder Minimum was characterized by strong sea level pressure reversals with high pressure centres over Northern or Northwestern Europe and large outbreaks of northeasterly cold continental air.With 3 Figures 相似文献
8.
Li Chongyin 《大气科学进展》1998,15(1):31-40
The data analyses found at first that the air—sea system in the northwestern Pacific region has clear systematical quasi—decadal
oscillation, such as the surface air temperature, the subtropical high activities over the northwestern Pacific and the SSTA
which has different time-scale features from the temporal variation with 3–4 years period of SSTA in the equatorial Pacific.
In East Asia, the climate variations, such as the surface air temperature, the precipitation and the beginning date of Mei-yu
in the Yangtze River basin, also have clear quasi-decadal oscillation. They can be regarded as the influences of quasi-decadal
oscillation of air-sea system in the northwestern Pacific region.
This research was supported by the Chinese Academy of Sciences and ‘95’ National Project- “Short-Range Climate Production
System”. 相似文献
9.
Summary Over the last 25 years the term “cold pool” has come to be used in many spheres as a synonym for floods. This has given rise
to a major confusion that has even moved into international scientific and technical circles. In this paper we analyse how
the concept of “cold air pool” has evolved from when it was defined at the beginning of the 20th century down to the present
day, in which the Spanish term “DANA” (similar to a cut-off low) has been introduced in order to avoid existing confusions.
In the course of the paper we take account of cold air pool genesis and their thermal and dynamic characteristics, and we
discuss the factors that have led to them being identified (erroneously) with heavy rainfall events. The study takes as its
basis a systematic analysis of all the cold air pools recorded in Europe, and particularly in the Iberian Peninsula, over
the period 1974–1983, as well as in studies of the floods recorded in eastern Spain since 1950 until nowadays. The discussion
done on the basis of this accurate analysis leads to the identification of a cold air pool as a type cut-off low (COL) and
justifying the use of this more generic term when a structure like this is present in a heavy rainfall event. For a better
illustration of the previous discussion and understanding of the role of COLs in intense rainfall events, we present the episode
of September 1971 in Catalonia, in which over 400 mm were recorded. The analysis was carried out with the MM5 initialised
with the ERA-40 re-analyses. The results show that the role of COLs in the heavy rainfall episodes recorded in Spain is mainly
dynamic, both in terms of the circulation they create at low levels and the potential vorticity anomaly generated. This circulation
draws in very warm, moist and potentially unstable air perpendicularly to the coast and the littoral mountain chains. The
factor of thermal instability, owing to the presence of cold air at medium and higher levels, shows itself to be more important
in zones where this warm moist advection at low levels is not as significant as in the Mediterranean zone. 相似文献
10.
利用2008年南京市23个自动气象观测站观测的气温资料,分析南京市城市热岛效应的空间分布及其变化特征。结果表明:南京市的热岛中心主要分布在人口和建筑物密集的鼓楼,白下和建邺区,下关、江宁和浦口等城区气温较低;2008年南京市平均城市热岛强度为1.6℃,四季热岛强度呈秋季、春季、冬季、夏季依次减弱;南京市城市热岛效应对城市居民生活影响较大。南京市热岛效应的逐渐增强,将导致夏季空调使用量的增加,增加能耗对创建低碳城市、建设和谐城市生活产生消极影响。 相似文献
11.
W. M. Connolley 《Climate Dynamics》1997,13(10):745-756
Using a hierarchy of climate models together with observations from gridded analyses, I examine the atmosphere-only and coupled
ocean-atmosphere variability in the general circulation for the region south of 40 °S. The variability in mean sea level pressure
(MSLP) is well simulated by the coupled models. A complication is that the difference between the two analyses used for verification
is comparable to the analysis-model differences. An increase in variability is seen within the hierarchy of model runs although
even a model without interannual variations in sea surface temperatures (SSTs) captures most of the observed variability.
The temporal variation in MSLP in southern high latitudes has a white spectrum consistent with “random” forcing by weather
events and a decoupling from oceanic “integration”. In contrast, the spatial pattern of MSLP variability shows large-scale
structure that is consistent between observations and various models, even without interannual variation in SSTs. This shows
that the models are sufficiently skillful to reproduce the pattern of observed variability and suggests that the pattern of
variability is a characteristic of the land-sea distribution and topography.
Received: 18 December 1996/Accepted: 23 May 1997 相似文献
12.
利用2008年南京市23个自动气象观测站气温资料,分析南京市城市热岛效应的空间分布及其变化特征。结果表明:南京市的热岛中心主要分布在人口和建筑物密集的鼓楼、白下区和建邺区,下关、江宁和浦口等城区气温较低;2008年南京市平均城市热岛强度为1.6℃,四季热岛强度呈秋季、春季、冬季和夏季依次减弱;南京市城市热岛效应对城市居民生活影响较大。南京市热岛效应的逐渐增强,将导致夏季空调使用量的增加,增加能耗对创建低碳城市、建设和谐城市生活产生消极影响。 相似文献
13.
Closure of the Panama Seaway during the Pliocene: implications for climate and Northern Hemisphere glaciation 总被引:1,自引:1,他引:0
The “Panama Hypothesis” states that the gradual closure of the Panama Seaway, between 13 million years ago (13 Ma) and 2.6 Ma,
led to decreased mixing of Atlantic and Pacific water Masses, the formation of North Atlantic Deep water and strengthening
of the Atlantic thermohaline circulation, increased temperatures and evaporation in the North Atlantic, increased precipitation
in Northern Hemisphere (NH) high latitudes, culminating in the intensification of Northern Hemisphere Glaciation (NHG) during
the Pliocene, 3.2–2.7 Ma. Here we test this hypothesis using a fully coupled, fully dynamic ocean-atmosphere general circulation
model (GCM) with boundary conditions specific to the Pliocene, and a high resolution dynamic ice sheet model. We carry out
two GCM simulations with “closed” and “open” Panama Seaways, and use the simulated climatologies to force the ice sheet model.
We find that the models support the “Panama Hypothesis” in as much as the closure of the seaway results in a more intense
Atlantic thermohaline circulation, enhanced precipitation over Greenland and North America, and ultimately larger ice sheets.
However, the volume difference between the ice sheets in the “closed” and “open” configurations is small, equivalent to about
5 cm of sea level. We conclude that although the closure of the Panama Seaway may have slightly enhanced or advanced the onset
of NHG, it was not a major forcing mechanism. Future work must fully couple the ice sheet model and GCM, and investigate the
role of orbital and CO2 effects in controlling NHG. 相似文献
14.
利用船测资料分析一次冷空气过程中东海海域海气通量特征及海洋表面热收支变化特征。2017年5月5日20时—6日14时冷空气过境期间,动量通量平均值为0.22 N·m-2。感热和潜热通量的平均值分别为27.17 W·m-2和90.25 W·m-2,是春季整个观测期间(2017年4月20日—5月26日)平均值的2.8倍和1.1倍。冷空气爆发当天,净热通量为-12.73 W·m-2,海洋失热。白天海表面热收入58.36 W·m-2,影响海面热收支变化的主要是净辐射通量和潜热通量。夜间海表面热支出156.89 W·m-2,海洋作为热源向大气释放潜热99.79 W·m-2,占海洋释放能量过程的63.61%,向大气释放感热27.11 W·m-2,占海表释放热量的17.28%,海表面损失的热量主要以潜热的形式向大气传输。 相似文献
15.
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
16.
E. Sh. Elizbarashvili R. Sh. Meskhiya M. E. Elizbarashvili L. D. Megrelidze 《Russian Meteorology and Hydrology》2009,34(12):838-842
The dynamics of frequency of warm and cold months for warm and cold periods of the year on the whole as well as for the ablation
period is studied for glaciers of the Greater Caucasus based on the analysis of maps on anomalies of monthly mean air temperatures
for the 1901–2000 period. A relation between the change in frequency of temperature anomalies and the glaciation area is established. 相似文献
17.
18.
D. N. Asimakopoulos C. G. Helmis K. H. Papadopoulos J. A. Kalogiros P. Kassomenos M. Petrakis 《Meteorology and Atmospheric Physics》1999,70(1-2):97-110
Summary According to past experience, the nearly stagnant conditions caused by the presumed equilibrium between the Saronikos Gulf
sea breeze and an opposing synoptic flow is identified as the principal mechanism leading to high pollution episodes in Athens
during the summer. However, previous experimental work has not examined in detail the interaction of the sea breeze flow with
the opposing background flow. In this context, recent experimental work covering the basic key-locations of the Athens Basin
focused on the inland propagation of the southerly sea breeze from the coast to the northern part of the basin mainly under
moderate northerly background wind. During this campaign, a network of four meteorological stations established along the
Athens Basin and a high range acoustic sounder at the centre of Athens operated over a two months time period in the summer
of 1993. In addition, tethered balloon flights in the centre of Athens and on a sea vessel about 15 km offshore were employed
during an experimental day with moderate opposing background wind. The results from this experimental campaign include the
documentation of the sea breeze delay and its intensity as a function of a sea breeze index and features of the vertical structure
of the sea breeze over land as well as over sea.
Received March 20, 1998 Revised October 12, 1998 相似文献
19.
This study presents the first 19th century cold season climate chronology for the Kingdom of Lesotho in southern Africa. The
chronology is constructed using a variety of documentary sources including letters, diaries, reports, monographs and newspaper
articles obtained from southern African and British archives. Information relating to cold season weather phenomena during
the austral autumn, winter and early spring months were recorded verbatim. Each of the cold seasons from 1833 to 1900 was
then classified as “very severe”, “severe” or “normal/mild”, with a confidence rating ranging from low (1) to high (3) awarded
against each annual classification. The accuracy of the document-derived chronology was verified against temperature data
for Maseru for the period 1893–1900. Excellent correspondence of the document-derived chronology with the Maseru instrumental
data and also with other global proxy temperature records for the 19th century is achieved. The results indicate 12 (18% of
the total) very severe, 16 (23%) severe and 40 (59%) normal/mild cold seasons between 1833 and 1900. The overall trend is
for more severe and snow-rich cold seasons during the early part of the study period (1833–1854) compared with the latter
half of the 19th century (with the exception of the 1880s). A reduction in the duration of the frost season by over 20 days
during the 19th century is also tentatively identified. Several severe to very severe cold seasons in Lesotho follow after
major tropical and SH volcanic eruptions; such years are usually characterized by early frosts, and frequent and heavy snowfalls.
The blocking of solar radiation and the enhanced northward displacement of polar fronts that are directly or indirectly associated
with volcanic events, may account for many of the most severe Lesotho winters during the 19th century. 相似文献