Relative influence of weather conditions and air pollutants on solar radiation – Part 2: Modification of solar radiation over urban and rural sites

Summary In the first part of this study, intensive measurements of particulate matter and trace gaseous were made to assess the characteristics of air pollutants in 14 sites covering most of Egypt, and to present a clear picture about the relationship of air pollutants with meteorology. The goal of this study is to examine the effect of weather conditions and air pollutants on the receipt of solar radiation during cloudless days at five sites. The results have shown, that the relative attenuation of the total solar radiation varied dramatically from 22% in winter to about 9.3% in summer. This finding may be attributed to PM₁₀ and CO effects, which are in the highest level during winter.     

气象条件对滨海旅游经济产出的弹性影响——以青岛为例

从计量经济学的角度,采用柯布-道格拉斯（Cobb-Douglas,C-D)生产函数模型,分析了不同气象变量对青岛地区滨海旅游的经济产出弹性影响。结果表明:滨海旅游经济产出与高温日数在1％水平下显著正相关,与降水日数、大雾日数、雷暴日数和大风日数均在1％水平下显著负相关;降水、雷暴、高温和大雾天气是影响经济产出的高敏感性因子,在每提高1％水平的情况下,其弹性影响分别达到-0.679％、-0.507％、0.311％和-0.288％;21世纪以来,青岛地区降水和雷暴天气呈减少的趋势,高温天气则呈增多的趋势,均有利于滨海旅游产值的增加。     

Summer interactions between weather regimes and surface ocean in the North-Atlantic region

This study aims at understanding the summer ocean-atmosphere interactions in the North Atlantic European region on intraseasonal timescales. The CNRMOM1d ocean model is forced with ERA40 (ECMWF Re-Analysis) surface fluxes with a 1-h frequency in solar heat flux (6 h for the other forcing fields) over the 1959–2001 period. The model has 124 vertical levels with a vertical resolution of 1 m near the surface and 500 m at the bottom. This ocean forced experiment is used to assess the impact of the North Atlantic weather regimes on the surface ocean. Composites of sea surface temperature (SST) anomalies associated with each weather regime are computed and the mechanisms explaining these anomalies are investigated. Then, the SST anomalies related to each weather regime in the ocean-forced experiment are prescribed to the ARPEGE Atmosphere General Circulation Model. We show that the interaction with the surface ocean induces a positive feedback on the persistence of the Blocking regime, a negative feedback on the persistence of the NAO-regime and favours the transition from the Atlantic Ridge regime to the NAO-regime and from the Atlantic Low regime toward the Blocking regime.     

The climate tourism potential of Alpine destinations using the example of Sonnblick, Rauris and Salzburg

The climate tourism potential of a region can be described by methods used in human biometeorology and applied climatology. Frequency analyses based on complex thermal bioclimatic indices (e.g. physiologically equivalent temperature) and diagrams of precipitation patterns based on thresholds offer new approaches of visualisation. An integral approach for tourism climatologic analyses is provided by the climate?Ctourism/transfer?Cinformation?Cscheme that also bases on frequency distributions of relevant factors and parameters which are important for a destination. The knowledge about the vertical variability of tourism climatologic factors is of high importance because of the several kinds of tourism activities affected by weather. The same holds for a quantification of extreme events like heat waves because of their possible effects on health and recreation over a year's course. The results show that the vertical gradient of bioclimatic and tourism-related parameters can be of value when developing strategies of adaption to climate change.     

合肥市雾日气象条件分析

利用合肥市气象观测站2005—2009年常规观测资料,统计分析了该市雾的月、季变化,及雾日地面气象要素特征;同时,应用后向轨迹和聚类分析的方法,研究了雾日大尺度输送特征。结果表明,合肥雾日数12月最多,7月最少;雾日局地气象条件表现为高湿、微风、偏东或西北风向;合肥雾日与输送形势关系密切,雾日近地层(10 m)以偏东方向的轨迹最多,在边界层中上部(1 000 m)以西南轨迹和本地轨迹最多。     

湖北省夏季旅游气候舒适度模糊综合评判

采用数学模糊评判方法,选取湖北省6个具有气候代表性站点30a(1978-2007年)夏季(6、7、8月)的逐日平均气温、相对湿度和风速资料,作为评价气候环境对人体舒适度的影响因素,并根据环境卫生学理论将舒适程度分为很舒适、舒适、较舒适和不舒适4个等级,对湖北省夏季旅游气候舒适度进行模糊评判分析.结果显示湖北省夏季旅游气候不舒适主要是由高温、高湿的综合作用所引起的.     

冬暖式大棚内茄子栽培气象条件分析

应用2003年1-4月、10-12月在寿光蔬菜基地的冬暖式大棚内茄子栽培生长情况所取得的温度、光照和湿度资料及同一时期外部环境气象资料,分析了冬暖式大棚内的温度、光照及湿度等气象条件对越冬茄子的影响情况,提出了改进措施。     

Relative influence of air pollutants and weather conditions on solar radiation – Part 1: Relationship of air pollutants with weather conditions

Summary Air pollution measurements from January 1999 to December 2003 were studied in 14 sites covering most of Egypt, with the aim of understanding the governing processes pollutants phase interaction. The nature of the contributing sources has been investigated, and some attempts have been made to indicate the role played by neighboring regions in determining the air quality at these sites. The seasonal variability of particulate matter (PM₁₀) and some gaseous pollutants (e.g., SO₂, NO₂, CO and O₃) were analyzed. Their relationships with meteorology were also examined. The results reveal that levels of major air pollutants were not significantly different at the rural and background sites during any season. On contrary the high atmospheric loading for PM₁₀, CO and SO₂ was frequently observed in winter at the urban sites. As expected, the prevailing winds were found to have an influence not only on air pollutants but also on the correlation between them.     

安顺供电与气象的关系

根据安顺供电对气象条件的需求,建立供电雷电监测系统,分析供电与气象要素之间的关系,提出对供电工程项目、安装维修有重大影响的气象指标。     

不同天气条件下沈阳城市热岛特征

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。     

11月份广州降水的天气形势及其系统配置

利用广州近10年11月的降水资源，分析其天气形势及其系统配置，并统计九运地期间广州出现降水的概率。     

辽宁省高速公路不良气象条件分析及服务探讨

对2005—2008年辽宁省高速公路交通事故资料进行统计。结果表明：辽宁省高速公路发生交通事故呈逐年上升趋势,其中由天气原因及其所引起的不良路况所造成的交通事故占20.4%,5—8月和11—翌年1月是此类交通事故的两个多发期。在各类天气现象中,因雾引起的交通事故所占比例最高,为41.0%,雨次之为31.3%。在此基础上就如何做好高速公路气象服务提出四点措施：划分灾害性天气服务关键性路段和关键期,制定高速公路安全运营气象灾害防御地方标准,在高速公路沿线布设密度适宜的气象监测站,加强气象对高速公路影响机理的研究。     

江西大雾的天气条件和形势特征分析

介绍江西冬、春季常出现的辐射雾、平流辐射雾的天气条件和形势特征。     

影响北京夏季O3污染的O3前体物浓度及天气条件分析

根据2003年北京夏季近地面大气光化学污染物观测资料,对中国气象局培训中心(代表站)O3超标日浓度、O3前体物浓度、不同天气条件下O3浓度分布特征等进行分析。结果表明:中国北京夏季NO2,NO,CO的浓度特征与日本神奈川县相似,白天(16:00以前)如果NO2/NO超过29,则容易出现O3超标;VOC浓度的高低影响O3浓度;当处于暖湿气流控制,地面为小风或静风、气温较高、湿度较大的多云天气时,易出现O3超标情况。这些污染物发生的特点和规律对北京大气光化学污染的研究和防治具有借鉴意义。     

北京城市浓雾特征及其与交通预报服务的关系

使用2007—2010 年北京地区18 个道面自动气象站能见度在1000 m 以下时的气象资料及同期北京管界内高速公路交通资料,对北京城市浓雾特征及其与交通预报服务的关系进行了探讨。结果表明: 1) 北京管界内高速公路封闭90%以上因浓雾引起。2) 浓雾具有明显的日变化和年变化,高发、低发时段分别在05—09 时和12—18 时,浓雾主要集中在9—12 月,6、7 月最少。3) 空间分布上,浓雾频次东南高,城区低,80%以上的浓雾出现在大兴和通州两区。4) 浓雾变化具有突发性和“象鼻形”先期振荡特征。5) 浓雾期间能见度变化与气象要素关系密切,近地面偏南风和偏东风最有利浓雾生成发展,西北风最有利浓雾消散;风速减小,气温下降,湿度增大,能见度降低,有利浓雾生成和发展;风速增大,气温升高,湿度减小,能见度上升,有利浓雾减弱消散;湿度减小滞后于能见度上升;浓雾维持阶段,各要素变化很小。     

Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone： Comparison between the Pearl River Delta and Yangtze River Delta Regions

In this paper, the online weather research and forecasting and chemistry (WRF-Chem) model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concentrations over the Pearl River Delta(PRD) and Yangtze River Delta(YRD) regions. Two scenarios of urban maps are used in the WRF-Chem to represent the early 1990s (pre-urbanization) and the current urban distribution in the PRD and the YRD. Month-long simulation results using the above land-use scenarios for March 2001 show that urbanization increases both the day- and night-time 2-m temperatures by about 0.6^oC and 1.4^oC, respectively. Daytime reduction in the wind speed by about 3.0 m s^-1 is larger than that for the nighttime (0.5 to 2 m s^-1). The daytime increase in the PBL height (> 200 m) is also larger than the nighttime (50--100 m). The meteorological conditions modified by urbanization lead to detectable ozone-concentration changes in the PRD and the YRD. Urbanization increases the nighttime surface-ozone concentrations by about 4.7%--8.5% and by about 2.9%--4.2% for the daytime. In addition to modifying individual meteorological variables, urbanization also enhances the convergence zones, especially in the PRD. More importantly, urbanization has different effects on the surface ozone for the PRD and the YRD, presumably due to their urbanization characteristics and geographical locations. Even though the PRD has a smaller increase in the surface temperature than the YRD, it has (a) weaker surface wind speed, (b) smaller increase in PBL heights, and (c) stronger convergence zones. The latter three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD than the YRD.     

Synoptic weather conditions and aerosol episodes over Indo-Gangetic Plains,India

The present study focuses on identifying the main atmospheric circulation characteristics associated with aerosol episodes (AEs) over Kanpur, India during the period 2001–2010. In this respect, mean sea level pressure (MSLP) and geopotential height of 700 hPa (Z700) data obtained from the NCEP/NCAR Reanalysis Project were used along with daily Terra-MODIS AOD₅₅₀ data. The analysis identifies 277 AEs [AOD₅₀₀ >  \( \overline{AOD} \) ₅₀₀ + 1STDEV (standard deviation)] over Kanpur corresponding to 13.2 % of the available AERONET dataset, which are seasonally distributed as 12.5, 9.1, 14.7 and 18.6 % for winter (Dec–Feb), pre-monsoon (Mar–May), monsoon (Jun–Sep) and post-monsoon (Oct–Nov), respectively. The post-monsoon and winter AEs are mostly related to anthropogenic emissions, in contrast to pre-monsoon and monsoon episodes when a significant component of dust is found. The multivariate statistical methods Factor and Cluster Analysis are applied on the dataset of the AEs days’ Z700 patterns over south Asia, to group them into discrete clusters. Six clusters are identified and for each of them the composite means for MSLP and Z700 as well as their anomalies from the mean 1981–2010 climatology are studied. Furthermore, the spatial distribution of Terra-MODIS AOD₅₅₀ over Indian sub-continent is examined to identify aerosol hot-spot areas for each cluster, while the SPRINTARS model simulations reveal incapability in reproducing the large anthropogenic AOD, suggesting need of further improvement in model emission inventories. This work is the first performed over India aiming to analyze and group the atmospheric circulation patterns associated with AEs over Indo-Gangetic Plains and to explore the influence of meteorology on the accumulation of aerosols.     

南京地区高温天气下城市化影响的模拟研究

利用WRF(Weather Research and Forecasting)模式耦合单层城市冠层模式,研究了南京地区一次高温热浪过程(2013年8月5—10日)中气溶胶的辐射效应、城市扩张对边界层的影响和它们间的相互作用。结果显示,由于气溶胶的直接辐射效应,在白天,南京近地面温度平均降低约0.11℃,净辐射平均降低约12 W/m~2;城市扩张使近地面温度增加约1.7℃,在本次试验过程中,城市扩张的增暖效应明显强于气溶胶冷却效应。另外,由于城市扩张后产生了较强的增暖作用,加强了周围气流的辐合运动,城市区域风速平均增加约0.8 m/s。白天潜热通量的减少与感热通量的增加导致城市边界层内温度升高,并且城市增暖引起的上升运动将气溶胶抬升至更高层,使边界层更不稳定,气溶胶与城市边界层稳定性之间可能存在正反馈。