青藏高原东部高寒草原地表能量交换特征(英文)

青藏高原是世界上面积最大、海拔最高的高原,其独特的地形地貌特征对东亚乃至全球大气环流有重要影响.由于地表特征不同,高原不同区域地表热力特征也有显著差异.高原的东部边缘地表、植被和气象特征与高原其他区域明显不同,因此这一区域地表热力作用也与高原其他区域不同.本文研究了青藏高原东部玛曲草原地表能量交换的季节变化特征.玛曲草原冬季净辐射占入射太阳辐射的比例小于雨季,其差异主要由2个季节的地表反照率和湿度状况的差异引起.全年来看,净辐射大部分用水汽蒸发所需的热量.冬季由于土壤冻结加之降水稀少,净辐射主要用于加热地表和大气.雨季由于相对较高的气温、充足的降水及植被茂盛的生长力,净辐射主要用于水汽蒸发.在这一区域,降水的季节分布以及土壤的冻融状况对地表能量分配有重要影响.     

臭氧总量测绘分光仪和臭氧监测仪紫外辐照度数据的对比研究

臭氧总量测绘分光仪(TOMS)和臭氧监测仪(OMI)是两个重要的已成功发射且涉及到紫外辐射波长的传感器,为紫外研究工作提供了重要的数据信息。但由于两者紫外产品的反演过程有资料和算法的一些区别使其在同一天的正午地表紫外辐射数据有一定差异,这使通过它们进行长时间尺度上的紫外辐射时空变化分析的精度和准确性受到一定影响。通过对相同时间段的两者正午地表紫外辐射数据进行对比分析,找到一个简单可行的方法使两者差异明显缩小。结果表明通过变换OMI紫外辐射值相对于TOMS紫外辐射值差异基本上调整到±10 mW/m2之间,说明该方法可以应用到后续OMI紫外数据上以便结合TOMS紫外数据进行整体紫外辐射时空变化研究。     

TOMS和OMI紫外辐照度数据的对比研究

臭氧总量测绘分光仪(TOMS)和臭氧总量测绘分光仪(OMI)是两个重要的已成功发射且涉及到紫外辐射波长的传感器,为紫外研究工作提供了重要的数据信息。但由于两者紫外产品的反演过程有资料和算法的一些区别使其在同一天的正午地表紫外辐射数据有一定差异,这使通过它们进行长时间尺度上的紫外辐射时空变化分析的精度和准确性受到一定影响。本文通过对相同时间段的两者正午地表紫外辐射数据进行对比分析,找到一个简单可行的方法使两者差异明显缩小。结果表明通过变换OMI紫外辐射值相对于TOMS紫外辐射值差异基本上调整到±10mW/m₂之间,说明该方法可以应用到后续OMI紫外数据上以便结合TOMS紫外数据进行整体紫外辐射时空变化研究。     

四氯乙烯和四氯化碳在红外测油中的差异性研究

正大气臭氧层位于距离地面20～50km处,可以有效地吸收太阳辐射,减少紫外线对地球上生物的伤害~([1])。因此,臭氧层是地球生物赖以生存的重要因素。臭氧层的破坏对人体健康、生物化学循环、水生态环境系统和植物等都具有重要影响~([2])。近年来,随着人类社会的发展,大气臭氧层的损害逐渐成为当今全球面临的首要环境问题。     

多模型综合的我国地表净辐射空间分布计算及时空变化

地表净辐射是地气系统的重要参数,在推动大气循环中发挥极大作用,准确估算其时空分布对于研究不同尺度气候变化及构建多种生态模型都具有重要意义。以2010年为例,通过精度分析得出1、2、3、4、5、8、9、11月回归法精度更高,误差绝对平均值约35.23MJ/m~2,标准差约28.67MJ/m~2,而6、7、10、12月彭曼修正式法推算值更接近辐射观测值,其误差绝对平均值约38.47MJ/m~2,标准差约28.683MJ/m~2。整体上回归法误差绝对平均值约36.36MJ/m~2,标准差约28.67MJ/m~2,精度优于彭曼修正式法。在上述思路的基础上,计算月尺度地表净辐射的空间分布,并对其时空变化进行了分析。结果表明:区域上,纬度是影响地表净辐射的重要因素,从低纬到高纬,地表净辐射逐渐减小,最大值出现在华南区,最小值出现在东北区;时间上,十年范畴内地表净辐射一直在波动,大体上呈逐年缓慢减小的趋势,在季节方面来说,地表净辐射呈现夏峰冬谷的状态,春季与秋季处于中间,而秋季略低于春季。     

青藏高原太阳紫外线辐射及其生物学效应研究现状

青藏高原是世界上紫外辐射最强烈的地区之一,受臭氧层减薄及夏季臭氧低谷效应的影响,使得该地区紫外辐射更加强烈,这引起了人们对该地区紫外辐射研究的关注。紫外辐射具有强烈的生物学效应,能够对人体、动物、植物、微生物造成普遍的影响甚至伤害。青藏高原强烈的紫外辐射为研究紫外辐射的生物学效应提供了天然实验场地及材料,为寻求生物抗紫外辐射的遗传响应、相关生理生化机制提供了可能。通过对这一地区生物群落和生态系统开展紫外辐射相关研究,有可能在强紫外辐射生态学研究上取得突破性进展。     

矿区土壤重金属生态毒性效应研究进展

本文介绍了影响土壤毒性的生物因素与非生物因素,列举陆生与水生生物评价方法(植物法、动物法和发光细菌法等),陆生生物评价方法成熟、操作简单;水生生物评价方法测试时间短、成本较低。生物评价可科学判定污染物对生态系统的长期影响,为理化评价重要补充。需在综合考虑各种因素的基础上对矿区土壤环境进行科学、全面评价。     

FY-3 SBUS数据和NOAA SBUV/2数据对比研究

FY-3 SBUS是我国第一个紫外臭氧垂直探测器,通过对SBUS数据和美国NOAA SBUV/2数据N值及臭氧垂直廓线对比,结果表明,SBUS臭氧垂直廓线相对于SBUV/2臭氧垂直廓线在大多数臭氧层具有较好的相对偏差,在±10%之间。在对比过程中,考虑了对比数据太阳天顶角匹配偏差、地理位置匹配偏差以及地表覆盖类型的影响。     

大气臭氧层与生物的演化

在影响生物演化的诸因素中,大气臭氧层是一个重要因素。当臭氧层不完善或遭受破坏时,紫外线就会令生物致伤致死,在晚元古代时,大气臭氧层还很薄弱.吸收紫外线的能力不强。进入罗圈冰期,陆缘海变浅,寒冷又使藻类减少,海水的透明度增大,紫外辐射增强而导致埃迪卡拉动物群的绝灭,白垩纪末期的绝灭事件与臭氧层的破坏有关,这是由慧星冲击引起的并造成了恶劣的环境,深海沉积物中所记录的各种地球化学异常可以用臭氧层破坏所产生的地球化学效应来加以解释.图1,参9.     

黄土高原半干旱区地表辐射特征

利用兰州大学半干旱气候与环境观测站地表辐射资料,分析了黄土高原半干旱区地表辐射的变化规律,并对该区地表辐射特征、地表反照率的年季变化及其影响机制进行了研究.结果表明:该区全年太阳总辐射较强,年平均值为204.2 W/m2,受地表状况和天气过程等因素影响,年变化表现出不规则或区域性特征.大气和地表对太阳辐射加热的响应需2个月,它们对地表辐射年变化的相对变幅达44.6%和38.9%,比干旱区的(100%)小,这说明该区云量年变化比干旱区的小,且大气和土壤对地表辐射变化的"缓冲"作用更强.反照率的年平均值为0.2432,比荒漠区小;其高值正好对应降雪过程和偏干旱时段,而低值则与降水、连绵阴雨的天气吻合.     

Effect of climate change relative to ozone depletion on UV exposure in subarctic lakes

The effect of stratospheric ozone depletion on increases in ambient levels of solar ultraviolet (UV) radiation in high-latitude regions' has raised concerns about the response of northern ecosystems to environmental change. The concentration of coloured dissolved organic material, which is derived from terrestrial vegetation and acts as a screen for ultraviolet radiation, is low in high-latitude lakes. The underwater light environment in these lakes is therefore likely to be sensitive to small variations in the supply of this material, in addition to the effects of ozone depletion. Here we use fossil diatom assemblages in combination with bio-optical models to estimate the magnitude of past variations in the underwater light regime of a lake at the boreal tree line. We find large shifts in underwater UV-B, UV-A and photosynthetically available radiation associated with changes in the input of coloured dissolved organic material into subarctic lakes during the Holocene. The inferred changes in biological exposure to UV radiation were at least two orders of magnitude greater than those associated with moderate (30%) ozone depletion. Our findings indicate that freshwater ecosystems at present located across vegetation gradients will experience significant shifts in underwater spectral irradiance through the effects of climate change on catchment vegetation and the export of coloured dissolved organic material.     

Effects of solar ultraviolet radiation on the photochemical efficiency, photosynthetic pigments and biomass production of Spirulina platensis

Effects of solar ultraviolet radiation (UVR) on Spirulina platensis were studied by investigating its photochemical efficiency, photosynthetic pigments and biomass production while exposed to full spectrum solar radiation or depleted of UVR for understanding how and to what extent UVR influences its photosynthe tic physiology and production. It was found that UVR brought about an extra inhibition of photochemical efficiency by 26%—30%. The greatest inhibition of pho tochemical efficiency in S. platensis was observed at noontime, and then recovered to some extent in late afternoon no matter which treatment they were exposed to. The contents of chlorophyll a, phycocyanin and carotenoids increased during initial stage of the exposure, but decreased with elongated exposure. UVR decre ased the biomass yield by about 6%. It indicated that filtering out UVR of solar radiation would raise the productivity of S. platensis, which is an important factor that should be considered in the production.     

兰州城区太阳紫外辐射及其与空气污染的关系

利用太阳辐射观测及环境空气质量监测资料，分析了各种天气状况下兰州城区太阳总辐射、紫外辐射的变化特征及其与空气污染的关系．结果表明：自1960-1998年地面接收的太阳辐射总体呈下降趋势，平均下降约12％．晴天紫外辐射占总辐射的4％-5％，紫外辐射的变化趋势与总辐射相同：兰州城区NOx，TSP质量浓度总体上呈下降趋势，O3质量浓度从1985-1989年有所下降，之后又呈上升趋势；紫外辐射与总辐射的比值与大气浑浊度因子S／D相关性较好，二者满足指数关系，相关系数蜘-0.79．兰州城区机动车NOx排放量随汽车保有量的快速增加而呈上升趋势．     

河北涞源太阳辐射的时空分布差异及资源应用可行性分析

当前大部分学者通常只研究太阳辐射大范围区域,对具体地域的研究很少;为此,对河北涞源太阳辐射的时空分布差异及应用可行性进行分析。给出河北莱阳地理位置;太阳辐射数据来源为当地气象站53599。采用Dubayyah太阳辐射估算法对太阳总辐射进行计算,把地表太阳辐射划分成太阳直接辐射、太阳散射辐射和周围地形反射辐射,采用求和方式求出总太阳辐射。给出涞源典型月份太阳直接辐射、散射辐射、周围地形反射辐射和总辐射时空分布差异分析结果,分析了涞源太阳辐射每天不同时段的时间分布差异。对太阳能资源光热转换和光电转换应用可行性进行分析。结果表明:涞源7月太阳辐射值最高,1月太阳辐射值最小,太阳能最佳利用时间为夏季中午;资源应用可行性强。     

Preparation of Modified Poly( ethylene terephthalate) Fibers and Their Properties of Ultraviolet Radiation Protection

Protection against solar ultraviolet radiation (UVR) among the general public has been increasing steadily. Poly(ethylene terephthalate) (PET) was blended with UVR protection agent and was spun into the modified fibers with the properties of UVR protection. An investigation on the properties using an ultraviolet spectrophotometer showed that the modified PET fabrics could be resistant to UVR more than 90% in the band of UV-B. The effect of the heat insulation and the mechanical properties of the fibers were also studied.     

紫外线辐射量变化原因分析

利用菏泽市气象局2003年紫外线辐射强度历史资料数据，统计分析了紫外辐射日变化和年变化规律，总结得出臭氧、太阳高度角、大气透明度和云的变化是影响紫外辐射强度的关键因素．     

紫外线辐射量变化原因分析

利用菏泽市气象局2003年紫外线辐射强度历史资料数据,统计分析了紫外辐射日变化和年变化规律,总结得出臭氧、太阳高度角、大气透明度和云的变化是影响紫外辐射强度的关键因素.     

中国云南地区地面紫外辐射观测

 在云南丽江(26°52′N,100°13′E)和勐腊(21°29′N,101°34′E)两地分别对以254nm和297nm为中心波长的太阳紫外辐射作了地面观测.观测时间为1999年7月～2000年5月.本文分析了两地紫外辐射的时空变化并初步讨论了与云量、臭氧总量的相关关系.研究结果表明:297nm波段的紫外辐射夏季强,冬季弱,具有明显的季节变化.丽江地区的紫外辐射在同一云量条件下高于勐腊地区,这可能是由海拔高度的差异引起.云量对两地的紫外辐射变化有强烈的影响,而当剔除云量、季节和随机变化等影响因素后,紫外辐射和臭氧总量呈现出了负的相关关系.     

Enhancements in biologically effective ultraviolet radiation following volcanic eruptions.

Aerosols injected into the stratosphere by large volcanic eruptions may induce ozone destruction through processes including heterogeneous chemical reactions. The effect of ozone reductions on surface ultraviolet irradiation is not obvious, however, because aerosols also increase the reflection of sunlight. Here we use a radiative transfer model to estimate the changes in biologically effective ultraviolet radiation (UV-BE) at the Earth's surface produced by the El Chichón (1982) and Mount Pinatubo (1991) eruptions. We find that in both cases surface UV-BE intensity can increase because the effect of ozone depletion outweighs the increased scattering.     

An influence of solar spectral variations on radiative forcing of climate

The thermal structure and composition of the atmosphere is determined fundamentally by the incoming solar irradiance. Radiation at ultraviolet wavelengths dissociates atmospheric molecules, initiating chains of chemical reactions-specifically those producing stratospheric ozone-and providing the major source of heating for the middle atmosphere, while radiation at visible and near-infrared wavelengths mainly reaches and warms the lower atmosphere and the Earth's surface. Thus the spectral composition of solar radiation is crucial in determining atmospheric structure, as well as surface temperature, and it follows that the response of the atmosphere to variations in solar irradiance depends on the spectrum. Daily measurements of the solar spectrum between 0.2?μm and 2.4?μm, made by the Spectral Irradiance Monitor (SIM) instrument on the Solar Radiation and Climate Experiment (SORCE) satellite since April 2004, have revealed that over this declining phase of the solar cycle there was a four to six times larger decline in ultraviolet than would have been predicted on the basis of our previous understanding. This reduction was partially compensated in the total solar output by an increase in radiation at visible wavelengths. Here we show that these spectral changes appear to have led to a significant decline from 2004 to 2007 in stratospheric ozone below an altitude of 45?km, with an increase above this altitude. Our results, simulated with a radiative-photochemical model, are consistent with contemporaneous measurements of ozone from the Aura-MLS satellite, although the short time period makes precise attribution to solar effects difficult. We also show, using the SIM data, that solar radiative forcing of surface climate is out of phase with solar activity. Currently there is insufficient observational evidence to validate the spectral variations observed by SIM, or to fully characterize other solar cycles, but our findings raise the possibility that the effects of solar variability on temperature throughout the atmosphere may be contrary to current expectations.