The first World Atlas of the artificial night sky brightness

We present the first World Atlas of the zenith artificial night sky brightness at sea level. Based on radiance-calibrated high-resolution DMSP satellite data and on accurate modelling of light propagation in the atmosphere, it provides a nearly global picture of how mankind is proceeding to envelop itself in a luminous fog. Comparing the Atlas with the United States Department of Energy (DOE) population density data base, we determined the fraction of population who are living under a sky of given brightness. About two-thirds of the World population and 99 per cent of the population in the United States (excluding Alaska and Hawaii) and European Union live in areas where the night sky is above the threshold set for polluted status. Assuming average eye functionality, about one-fifth of the World population, more than two-thirds of the United States population and more than one half of the European Union population have already lost naked eye visibility of the Milky Way. Finally, about one-tenth of the World population, more than 40 per cent of the United States population and one sixth of the European Union population no longer view the heavens with the eye adapted to night vision, because of the sky brightness.     

Millimetre and submillimetre τ relations

Relations are presented between the optical depth of the atmosphere  (τ)  in the millimetre and submillimetre windows at 350, 450, 850 and 1250 μm. These relations are derived by an analysis of 849 skydips at 850 μm performed with the submillimetre camera SCUBA at the James Clerk Maxwell Telescope (JCMT) and polynomial fits to over 19 000 measurements of a tipping radiometer operating at 350 μm. The relations allow for an improved calibration of millimetre and submillimetre observations on Mauna Kea, Hawai'i, and for better monitoring of atmospheric conditions.     

A mineral magnetic and scaled-chrysophyte paleolimnological study of two northeastern Pennsylvania lakes: records of fly ash deposition, land-use change, and paleorainfall variation

A combined mineral magnetic and scaled chrysophyte study of lake sediments from Lake Lacawac and Lake Giles in northeastern Pennsylvania was conducted to determine the effects of land-use and sediment source changes on the variation of pH, conductivity, and alkalinity inferred from biotic changes. Ten 30–40 cm long gravity cores were collected from Lake Lacawac and three from Lake Giles. Isothermal remanent magnetizations (IRMs) were given to the lake sediments in a 1.3 T magnetic field to measure magnetic mineral concentration variations. IRM acquisition experiments were conducted to identify magnetic mineralogy. The bedrock, soils and a peat bog on the shores of Lake Lacawac were also sampled for magnetic analysis to determine possible lake sediment sources. The top 10 cm of sediment collected from Lakes Lacawac and Giles was two to four times more magnetic than deeper sediment. ²¹⁰Pb dating suggests that this intensity increase commenced circa 1900. SEM images of magnetic extracts from the highly magnetic sediments indicates the presence of magnetic fly ash microspheres from fossil fuel burning electric power generation plants. The similarity in magnetic coercivity in the top 8 cm lake sediments and in the peat bog supports an atmospheric source for some of the magnetic minerals in the youngest lake sediments. The highly magnetic sediments also contain an antiferromagnetic mineral in two cores closest to Lake Lacawacs southeastern shore. This magnetic mineral is only present deep in the soil profile and would suggest erosion and significant land-use changes in the Lacawac watershed as another cause for the high magnetic intensities (concentrations) in the top 10 cm of the lake sediments. The most significant changes in the scaled chrysophyte flora occurred immediately above the 10 cm level and were used to infer a doubling of the specific conductivity between circa 1910 and 1929. These variations also support land-use changes in the Lacawac catchment at this time. A similar shift in the scaled chrysophte flora was not observed in the top of Lake Giles, however, distinct changes were found in the deeper sections of the core coupled with a smaller peak in magnetic concentration. Fourier analysis of the ²¹⁰Pb-dated lake sediment magnetics indicates the presence of a 50 year period, low amplitude variation in the Lake Lacawac, Lake Giles, and Lake Waynewood (Lott et al., 1994) magnetic concentration records. After removal of the land-use/fly ash magnetic concentration peak by Gaussian filtering, the 50 year variation correlates strongly from lake to lake even though the lakes are in different watersheds separated by up to 30 km. When this magnetic variation is compared with Gaussian-filtered rainfall variations observed in New York City and Philadelphia over the past 120–250 years there is a strong correlation suggesting that magnetic concentration variations can record regional rainfall variations with an approximately 50 year period. This result indicates that magnetics could be used to document regional variations in climatic change.     

河南\

随机抽查统计了大气科学类18种核心期刊和15种省级刊物中的50期共计605篇论文,发现38%左右的关键词或摘要撰写存在欠规范的问题。为了提高学术论文的撰写质量,对大气科学类学术论文中关键词标引和摘要撰写存在的问题及解决方法进行了探讨。研究表明：关键词主要存在选用通用词、漏选关键词、标引深度不合适、排列顺序混乱等不足,摘要比较常见的问题则表现在基本要素残缺、嵌入不当信息、结果（结论）笼统空泛。该研究指出：关键词的选取以《汉语主题词表》中的叙词为主,可适当搭配新型交叉学科、新理论、新技术中出现的科技术语和专有名词,忌选通用词;应遵循“选准、选全”的原则,从题名、摘要、层次标题、结论乃至正文中提取能完整表达论文主题、具有检索价值的主题词,以4~5个为宜;其排序应遵循一定的逻辑规则。摘要应包含目的、方法、结果、结论四要素;避免使用第一人称、嵌入背景知识、自我见解和主观评价;结果（结论）部分要逻辑清晰、言之有物、定量直观,让读者能透过研究结果窥见论文的核心价值。该文还提出了提炼摘要四要素的四个步骤及大气科学类摘要的三种常见写作格式。

     

大气CO2浓度升高对土壤中不同粒级碳的影响

不同粒级土壤中的碳有着不同的周转规律，在高CO2浓度条件下，它们含量的变化将在一定程度上反映土壤碳是累积还是减少，对明确土壤碳的变化趋势有重要意义．采用田间培养试验初步模拟研究在高CO2浓度条件下土壤不同粒级碳的分布．结果表明，加入秸秆培养1年，由于CO2浓度升高的原因导致在低氮（LN）、常规氮（NN）和高氮（HN）水平下土壤中碳分别增加0．01、1．10、1．22g／kg，表现为粒级〈53μm土壤颗粒中碳分别增加1．53、2．19、2．70g／kg．粒级〈53μmm土壤颗粒碳量的增加，主要是由于其重量分配百分数显著增加36．2％，碳浓度增加5．4％；粒级〉250μm和250～53μm土壤颗粒部分虽然其碳浓度分别增加20．8％和17．3％（P〈0．05），怛由于重量分配百分数分别显著降低22．8％和36．1％，结果碳量降低．试验表明高CO2浓度导致不同粒级土壤的分配及碳浓度的变化；高氮施肥水平下有增加土壤碳量特别是小粒级土壤碳量的趋势．     

GEOGRAPHY AND THE LESSONS FROM EL NIÑO∗

Recognized for years as a major environmental disruption, El Niño generated intense public interest in 1982–1983. During its last occurrence, this phenomenon, which develops in the tropical Pacific and usually affects rimlands of the Pacific basin, exceeded its boundaries and its effects were transmitted to continental North America, Europe, Africa and East Asia. Notwithstanding its vast areal extent, the interest of geographers in El Niño events, past and recent, has been comparatively less than that demonstrated by natural scientists and ecologists: little has been accomplished to place these climatic-ecological crises within global perspective. Lessons from El Niño include the acknowledgement of new concepts of climatic transitivity, ocean dynamics and energy exchanges that must find a place within the conceptual wealth of geography if this science intends to keep up with the rapid progress of other geosciences.     

基于OMI卫星数据的城市对流层NO2变化趋势研究

利用OMNO2全球产品卫星遥感资料研究科技城市北京、交通城市黄骅港、旅游城市三亚、特区城市深圳和工业城市抚顺的NO2月平均变化情况。通过Beat软件和IDL联合编程对该产品进行处理,得到各城市对流层NO2垂直柱密度的月平均值;对各城市2004年10月至2007年10月的NO2月平均变化进行线性正弦模型模拟,得到月平均变化趋势和月增长率,并评价变化趋势的精度。结果显示,各城市在冬季NO2对流层垂直柱密度较大,夏季较小,季节性循环明显。北京、黄骅港、三亚、抚顺在这段时间NO2总体呈增加趋势,从大到小依次是:抚顺、北京、黄骅港和三亚,深圳呈减少趋势。根据趋势显著性判别准则,各城市的NO2月平均变化均显著。另外相对于2004年10月,月相对增长率从大到小依次是抚顺、三亚、黄骅港、北京、深圳,其中深圳的NO2呈现负增长。     

大气垂直折射与时序垂直角值的谱分析

本文介绍了对时序垂直角观测值进行谱分析的方法和所得到的结论。使以往对于大气折射影响及其变化规律的定性认识得以定量化。     

用于极地的中尺度大气模式Polar MM5的改进和检验

介绍了一个用于极地研究的中尺度大气模式———Polar MM5,阐述了该模式区别于标准的中尺度大气模式MM5的动力学和物理特征。利用Polar MM5获得了10 d的模拟结果表明,Polar MM5能较好地模拟高纬度地区近地面气象变量特征,尤其是对近地面温度和水汽混合比可得到高精度模拟结果,证实了在高纬度地区对标准MM5所进行的物理参数化方案的改进是切实有效的。