Seasonal to sub-seasonal variations of the Asian Tropopause Aerosols Layer affected by the deep convection, surface pollutants and precipitation

The Asian Tropopause Aerosols Layer (ATAL) refers to an accumulation of aerosols in the upper troposphere and lower stratosphere during boreal summer over Asia, which has a fundamental impact on the monsoon system and climate change. In this study, we primarily analyze the seasonal to sub-seasonal variations of the ATAL and the factors potentially influencing those variations based on MERRA2 reanalysis. The ability of the reanalysis to reproduce the ATAL is well validated by CALIPSO observations from May to October 2016. The results reveal that the ATAL has a synchronous spatiotemporal pattern with the development and movement of the Asian Summer Monsoon. Significant enhancement of ATAL intensity is found during the prevailing monsoon period of July–August, with two maxima centered over South Asia and the Arabian Peninsula. Owing to the fluctuations of deep convection, the ATAL shows an episodic variation on a timescale of 7–12 days. Attribution analysis indicates that deep convection dominates the variability of the ATAL with a contribution of 62.7%, followed by a contribution of 36.6% from surface pollutants. The impact of precipitation is limited. The ATAL further shows a clear diurnal variation: the peak of ATAL intensity occurs from 17:30 to 23:30 local time (LT), when the deep convection becomes strongest; the minimum ATAL intensity occurs around 8:30 LT owing to the weakened deep convection and photochemical reactions in clouds. The aerosol components of the ATAL show different spatiotemporal patterns and imply that black carbon and organic carbon come mainly from India, whereas sulfate comes mainly from China during the prevailing monsoon period.     

中国区域紫外辐射红斑剂量时空变化特征

利用大气探测卫星AURA搭载的臭氧观测仪（ozone monitoring instrument,OMI）所获得的紫外辐射红斑剂量数据,分析了2005—2015年中国紫外辐射的时空变化特征。在空间上,紫外线辐射呈现纬度地带性分布,从南向北逐渐减小,大约从4200 J?m^?2到1500 J?m^?2递减。紫外辐射与高程呈现明显的正相关,东部、东北的低海拔地区,紫外辐射相对较低。在高海拨的青藏高原区,紫外辐射高,多年平均值大约为5500 J?m^?2,有些区域可达6000 J?m^?2以上。在时间上,紫外辐射红斑剂量存在明显的季节变化,一年中变化大致呈现抛物线分布。在夏季（7月份）达到最大值,多年平均值为5532.9 J?m^?2,春秋季次之,冬季（12月份）达到最小值,多年平均值为1089.2 J?m^?2。2005—2015年平均紫外线辐射呈上升趋势,但是在2010年出现谷值,多年平均值大约为3016.5 J?m^?2。不同区域的变化趋势表现出明显的空间差异,大体呈现两种模式：在高值的青藏高原区,紫外辐射呈现减少的趋势;在低值区,紫外辐射呈现逐渐增大的趋势。     

海上溢油指纹鉴别技术现状及展望

简要回顾了海上溢油污染概况,介绍了国内外溢油鉴别方法:气相色谱法、气相色谱-质谱法、荧光光谱法、红外光谱法等,指出了未来海上溢油指纹鉴别技术的发展方向。     

Case study of dust event sources from the Gobi and Taklamakan deserts: An investigation of the horizontal evolution and topographical effect using numerical modeling and remote sensing

A severe dust event occurred from April 23 to April 27, 2014, in East Asia. A state-of-the-art online atmospheric chemistry model, WRF/Chem, was combined with a dust model, GOCART, to better understand the entire process of this event. The natural color images and aerosol optical depth (AOD) over the dust source region are derived from datasets of moderate resolution imaging spectroradiometer (MODIS) loaded on a NASA Aqua satellite to trace the dust variation and to verify the model results. Several meteorological conditions, such as pressure, temperature, wind vectors and relative humidity, are used to analyze meteorological dynamic. The results suggest that the dust emission occurred only on April 23 and 24, although this event lasted for 5 days. The Gobi Desert was the main source for this event, and the Taklamakan Desert played no important role. This study also suggested that the landform of the source region could remarkably interfere with a dust event. The Tarim Basin has a topographical effect as a “dust reservoir” and can store unsettled dust, which can be released again as a second source, making a dust event longer and heavier.     

大寨沟污水净化实验研究

针对大寨沟水质特色,选用化学处理方法,设计了处理工艺流程.通过实验确定了絮凝剂,探讨了絮凝剂的制备要点,在最佳的投药量下,色度和浊度的去除率分别可以达到80%和90%以上.实验最终出水可以达到综合回用标准,表明化学处理方法对大寨沟污水有很好的净化效果.     

镉在鲤鱼组织内的蓄积及对血浆指标的影响

随着工业的迅速发展,水环境中的镉污染日趋严重,镉的蓄积性强,毒性高。为了进一步研究镉在鱼类不同组织内的蓄积及其对血浆指标的影响,以鲤鱼(Cyprinus carpio)为受试生物,设置3个浓度梯度,镉浓度分别为0(对照组)、5和50μg·L-1,试验周期为30d。结果显示,随着暴露时间的延长,染毒组鲤鱼鳃、肝胰脏和肾脏中镉蓄积量与对照组相比均显著升高(p<0.05),其中肾脏蓄积量最大,其次为肝胰脏和鳃,且50 μg·L-1染毒组各组织镉蓄积量显著高于5 μg·L-1染毒组(p<0.05);30d时,5和50 μg·L-1染毒组鳃、肝胰脏和肾脏中镉蓄积量分别为对照组的12.3和43.5倍、5.1和27.3倍、11.9和70.8倍;鲤鱼肌肉中仅检测到微量镉(0.02～0.04mg·kg-1),且暴露时间和镉暴露浓度不影响肌肉中镉的蓄积量。整个试验期间,各染毒组血浆中钙和磷含量、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和谷草转氨酶(GOT)活性与对照组相比无显著差异(p>0.05)。研究表明,不同程度的水体镉污染均能造成鲤鱼各组织(肌肉除外)内较高浓度的镉蓄积,但对血浆指标无显著影响。     

海域环境影响对比分析在铁矿石港竣工环保验收中的应用

通过对马迹山矿石中转港扩建工程竣工环境保护验收阶段在码头前沿区、锚地、航道和对照点处,海水水质、海洋表层沉积物、海洋生物的监测调查数据,进行与环评时期的阶段对比和各监测点之间的区域对比评价,分析工程竣工后对周边海洋生态环境的影响。以对比分析结果为基础,判断工程是否具备竣工环保验收条件。     

深圳市主要饮用水水库水质的评价

采用标识指数法和污染指数法,评价和分析了深圳市13个主要饮用水库的水质状况。研究结果表明,深圳市饮用水库营养盐浓度较高,总氮和总磷超标的水库分别占92.3%和38.5%。按单因子评价法,石岩水库为Ⅴ类,深圳水库和罗田水库为Ⅳ类,梅林水库刚好达到Ⅱ类,其余水库为Ⅲ类。两种评价方法一致,而标识指数法不仅可以判断水质是否超标,而且能够确定水质具体类别,具有计算简单、分析结果直观等优点。     

工业增加值与废水排放量之间的关系研究

使用投入产出模型研究了中国工业各部门的生产增加值与其废水排放量之间的关系,提出了完全废水排放系数的计算方法,计算出工业各部门的直接废水排放系数和完全废水排放系数,并对两种废水排放系数的变化原因进行分析,根据废水处理效果的不同给出政府对相应的工业部门应该采取的治理措施,并认为废水排放治理要综合考虑产业结构、管理水平和生产规模等方面的因素,仅仅考虑提高废水处理技术是不够全面的。     

陕西省大气污染源二噁英排放量估算研究

在结合实际确定陕西省二噁英的主要排放源及其排放因子基础上,采用国际通用的气体排放量计算法估算了陕西省2000年-2008年的二噁英年排放量,并就排放量的构成和变化趋势进行分析。结果显示:二噁英的年排放总量呈增长趋势,介于27.67 98.39 g TEQ之间;能源消耗产生的二噁英居于首位,其排放量约占总排放量的50%。工业燃料燃烧和工业生产过程所排放的二噁英占年排放量的60%以上,控制工业污染源的二噁英排放势在必行。