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1.
南海古生产力研究进展   总被引:3,自引:0,他引:3  
海洋表层水中的浮游生物通过光合作用和沉降作用,将碳从真光层“泵”入深海,从而使海洋表层生产力、CO2浓度与全球气候3个环节连接起来。海洋存储的CO2是大气的60倍,因此,在相当程度上,海洋控制着大气中CO2浓度的变化,海洋生产力控制着全球碳循环,从而对全球气候变化产生极大的影响。因此,研究海洋生产力的变化,对于理解全球环境变迁有着重要的意义。  相似文献   

2.
CO2的海气通量对于研究全球气候变化具有重要的意义。海洋微表层作为CO2在海洋和大气之间传输的重要通道,对于准确估算全球海气CO2通量的大小非常重要。本文主要从微表层中表面活性物质的富集,温度的偏低和与CO2的化学反应3个方面,综述了近年来与微表层相关的CO2通量研究进展,并对未来的相关研究进行了展望。  相似文献   

3.
海洋酸化研究进展   总被引:6,自引:1,他引:5  
<正>海洋是巨大的碳库,不断地从大气吸收CO2,工业革命以来,海洋吸收了人类向大气排放CO2的30%~40%[1]。海洋吸收的CO2对于缓解全球变暖起着重要的作用,但是它破坏了海洋自身碳酸盐的化学平衡,导致海水酸度增加。这种由于海洋吸收了大气中人为CO2引起的海水酸度增加过程,被称为海洋酸化。目前全球海洋正处于5500万年以来海洋酸化速度最快的时期,工业革命以来,全球表层海水pH已  相似文献   

4.
海水中溶解无机碳DIC的分析方法   总被引:4,自引:0,他引:4  
海洋CO2是全球碳循环至关重要的纽带,分析测定海水中CO2体系各存在形式的含量及分布,对于探究CO2在海洋中的转移和归宿,海洋吸收转移大气中的CO2的能力以及CO2在海洋中的循环机制等都具有十分重要的意义,本文对海水中溶解无机碳的各种测定方法作了概括和总结,分别对各种方法的特点,原理、发展及前景进行了综述。  相似文献   

5.
CO2是引起全球气候变暖的最重要温室气体。大气中过量CO2被海水吸收后将改变海水中碳酸盐体系的组成,造成海水酸化,危害海洋生态环境。本文采用局部近似回归法对2013年12月—2014年11月期间西沙海洋大气CO2浓度连续监测数据进行筛分,得到西沙大气CO2区域本底浓度。结果表明,西沙大气CO2区域浓度具有明显的日变化和季节变化特征。4个季节西沙大气CO2区域本底浓度日变化均表现为白天低、夜晚高,最高值405.39×10-6(体积比),最低值399.12×10-6(体积比)。西沙大气CO2区域本底浓度季节变化特征表现为春季和冬季高,夏季和秋季低。CO2月平均浓度最高值出现在2013年12月,为406.22×10-6(体积比),最低值出现在2014年9月,为398.68×10-6(体积比)。西沙大气CO2区域本底浓度日变化主要受本区域日照和温度控制。季节变化主要控制因素是南海季风和大气环流,南海尤其是北部海域初级生产力变化和海洋对大气CO2的源/汇调节作用。  相似文献   

6.
大洋"生物泵"--海洋浮游植物生物标志物   总被引:5,自引:0,他引:5  
海洋浮游植物承担着目前地球上光合作用的一半任务,对大气CO2浓度和全球碳循环有重要的调控作用。从“铁假说”到“硅假说”,反映了大洋“生物泵”尤其是海洋中的不同浮游植物群对过去气候变化的响应和反馈。根据不同浮游植物产生的特定生物标志物可以定量再造海洋浮游植物群落组成,如岩藻黄素、CO2甾醇主要来自硅藻;而19’-己酰氧基岩藻黄素、C37—C39烯酮主要来自定鞭藻中的颗石藻。许多研究已成功利用现代环境中的色素和古代沉积物中的类脂物质,恢复水体中不同浮游植物的生物量和群落组成。虽然目前海洋浮游植物与生物标志物之间的关系还有待完善,但与其他方法相比仍不失为一种快速、有效的方法,在未来的海洋环境检测和古气候研究领域有重要的应用前景。  相似文献   

7.
海洋浮游植物在海洋生态、环境和全球气候变化中担当着非常重要的角色,对大气CO2浓度有重要的调节作用。从早期的测氧法、放射碳法,到对生物总量研究的流式细胞测量技术和遥感观测,以及对群落结构研究的分子生物技术、色素和脂类化合物等化学方法,都极大地促进了海洋浮游植物的研究。南海地理位置独特,是西太平洋上最大的边缘海之一,同时受亚洲季风的强烈影响。在对浮游植物主要研究方法介绍的基础上,总结了南海现代海洋浮游植物的群落分布和时空变化特征,归纳了气候、环境等各种因素对浮游植物生态的影响,同时探讨了南海古生产力的演变特征和影响因素。  相似文献   

8.
钙同位素是近20a来才被人们关注的海洋中阳离子同位素,通过对东北印度洋近30万a来冰川旋回中浮游有孔虫Globigerinoides sacculifer 壳体δ44Ca的研究,并与δ18O和δ13C的对比分析给出了冰川旋回中水圈、气圈、生物圈的Ca循环和C循环的一般模式:当大洋生产力升高时,由于海洋生物构建硬体的需要取走大量CaCO3,生物固定Ca2+和CO2的"泵"功能增强,海水中δ44Ca值升高,引起大气CO2浓度降低,促进了全球气候变冷;当大洋生产力降低、生物总量减少时,生物对Ca同位素分馏的弱化和对CO2需求的减少,必然导致大洋海水中δ44Ca值降低和CO2浓度的升高,大量CO2逸出海面,作为全球 CO2的"源"促使大气中CO2浓度升高.  相似文献   

9.
在有关全球变暖的争论中.海洋对全球变暖起什么作用是关键问题之一.在对下一个世纪预测时人们提出海洋将通过吸收大量的热量来抑制全球变暖.Manabe和Stouffer(1993)看得更远些,他们撰文指出如果CO2持续释放到大气中使其浓度加倍,则北大西洋的热传送“输送带”作用将减弱,在一定的时间条件下还能恢复;但如果其浓度达到4倍时,  相似文献   

10.
海洋-大气二氧化碳通量的观测技术   总被引:5,自引:1,他引:4  
大范围稳定地获取海洋-大气系统中二氧化碳的精确数据,是海洋科学、大气科学以及全球变化科学和可持续发展科学计划中的重要任务.准确评估海-气CO2通量需要对海洋和大气中相关参数的同步精确连续观测,需要发展和建立海-气CO2通量的立体观测平台.该观测平台包括岸基、船基、航空、卫星和浮标等系统,主要技术包括走航大气和海水观测技术、浮标海-气CO2通量观测技术、极区海洋-大气CO2通量的观测技术和遥感海洋-大气CO2通量观测和评估技术.  相似文献   

11.
On the basis of satellite observations of column carbon monoxide (CO) and total ozone (TO), an analysis has been performed of the connection of the interannual variability of CO with the quasi-biennial oscillation (QBO) of the equatorial stratospheric wind and the QBO of total ozone. It is found that the CO total colomn over most of the globe in the westerly phase of the QBO is greater than that in the easterly phase. The global distribution of the CO QBO amplitudes exhibits a local maximum over Indonesia, where the peak-to-peak amplitude of the CO QBO signal averages 15% of the local annual mean CO in this region. Analysis shows that the QBOs of CO are well synchronized with the QBO of wind at 50 hPa. At the same time, a joint analysis of the characteristics of the CO QBO and TO QBO demonstrates no direct photochemical coupling between of the quasi-biennial variations of TO and CO.  相似文献   

12.
The results of measurements of the total content of carbon monoxide in an atmospheric column over Moscow and the Zvenigorod Scientific Station (ZSS) are given for the period 1993–2005. The simultaneous measurements of the regional background contents of carbon monoxide over a rural area (ZSS) and over Moscow made it possible to isolate an urban portion of the CO content. The total content of CO over the city varies significantly from day to day from values close to the background value to values that are 2.5–3 times greater than the background value. The number of days with such a CO content is 5% of the total number of measurement days. Such a CO content is most often observed during the cold seasons. During the warm seasons, in most of the cases, slight excesses of the CO background value are observed in the urban atmosphere. Variations in the CO content are determined mainly by wind-velocity variations and temperature inversions. In 2002, the high CO concentrations were due to forest and peatbog fires. On some days, over the ZSS, the concentrations of CO were high as never before. Over this period (12 years), the CO content in the surface air layer over the city did not increase.  相似文献   

13.
The emissions from fires in the boreal zone of northern Eurasia significantly contribute to the global emissions of greenhouse gases, their precursors, and aerosols. These emissions are an important component of the global carbon balance, and they significantly affect both seasonal and long-term variations in the chemical composition and radiation properties of the atmosphere on both regional and global scales. The atmospheric emissions of carbon monoxide (CO) from biomass burning have systematically been estimated for the entire territory of northern Eurasia over the period of 2000–2008 on the basis of satellite (MODIS MCD45A1) data on burned vegetation and the Seiler-Crutzen emission model with consideration for both regional and seasonal features. On the whole, for Russia, the annual emissions of CO from biomass burning ranged from 10.6 to 88.2 Mt/y over the indicated period. Depending on fire activity, the atmospheric emissions of CO from natural fires and agricultural work may yield from 25 to 200% of the total technogenic emissions according to the EDGAR-2000 model. In this case, the dominant contribution is made by boreal forest fires (8–57 Mt/y), whose portion amounts to 63–76% of the total emissions from biomass burning. This relatively short observational series does not allow one to reliably estimate long-term variations; however, on the whole, a stable increase in burned areas has been observed in forest, steppe, and agricultural regions over the last decade. Our analysis suggests significant spatial and seasonal variations in the large-scale fields of fire emissions, which are determined by the physical, geographic, and climatic features of individual regions. The calculated fields of emissions can be used in transport-chemical models, studies of the regional transport and quality of air, and climate models.  相似文献   

14.
The spatial and temporal variabilities of the aerosol optical thickness (AOT) and the total carbon monoxide content (CO) in the period of development and weakening of mass forest and peatbog fires in the European Russia territory (ERT) in the summer of 2010 are investigated from data of the AOT and CO satellite observations. The intensities of aerosol and CO emissions in the period of mass fires and the ratio of the emission factors of aerosol particles and CO are estimated on the basis of calculations of the smoke and CO masses over the ERT. The interrelation between variations in the levels of the regional pollution by combustion products and the variability of meteorological parameters is investigated. Various aspects of the manifestation of radiation effects of aerosols are discussed. The synchronization of weekly signals of the AOT, CO, and meteorological parameters in the period of mass fires is noted.  相似文献   

15.
The results of the carbon monoxide total content measurements over Moscow and Zvenigorod for 2005–2008 are compared with the same data sets for Moscow 1986–2005 and Beijing, 1992–2007. Two identical medium resolution diffraction spectrometers (resolution 0.2 cm?1) with solar tracking system were used. The CO total content measured simultaneously over the city and over Zvenigorod Scientific Station (ZSS) of the Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences (60 km west from Moscow). This method allows to isolate an urban part of CO content. The acoustic locator SODAR LATAN-3 measurements permitted us to study the influence of the carbon monoxide ventilation conditions upon level of pollution. Correlation coefficients between the urban part of CO content and average wind speed for cold and warm seasons were obtained. The data sets analysis showed a preeminent effect of the wind within boundary layer (up to 300 m) over the CO ventilation. The urban part of the CO content hasn’t increased in spite of more than quintuple increase of the motor-vehicles number in Moscow. An increase of the rural CO total column for the 1970–1985 has transformed into its virtually stable amount in between of 1986 to 2000, changed then to a decrease for 2001–2008. We noted the 2008 as “the year of the CO total column minimum” over the past decade. The effect of urban CO sources influence on the CO total column in rural area is small, i.e. on a level of 3% of the total number of measurements. The number of extremal daily values for Moscow is estimated as 5%, and 20% for Beijing.  相似文献   

16.
海洋中生源活性气体的来源与迁移转化   总被引:1,自引:1,他引:0  
杨桂朋  张洪海 《海洋学报》2018,40(10):14-21
海洋生源活性气体主要包括二甲基硫(DMS)、甲烷(CH4)、氧化亚氮(N2O)、一氧化碳(CO)、挥发性卤代烃(VHCs)和非甲烷烃(NMHCs)等。它们通过海-气交换进入大气,不仅在全球碳、氮和硫循环中发挥关键作用,而且会直接或间接地对环境和气候变化产生重要影响。海洋释放的活性气体一类属于温室效应气体(CH4、N2O、VHCs和CO等),另一类会在大气中发生化学反应,控制着大气氧化平衡和臭氧浓度(VHCs和NMHCs)。而DMS属于负温室效应气体,其在大气中被快速氧化形成硫酸盐气溶胶,进而对云的形成和辐射强迫产生重要影响。本文综述了国内外海洋生源活性气体的研究现状,着重介绍了DMS、CH4和N2O的来源、迁移转化、海-气通量及其影响机制,并指明了该领域存在的科学问题及今后的研究方向。  相似文献   

17.
The design, construction, and performance of a non-contaminating titanium sampler for carbon monoxide (CO) are described. In light of the favorable properties of titanium and the minimal contact of O-rings with samples, this multi-purpose design is expected to excel at a broad range of other uses: sampling gases, organic compounds, some trace metals, and living and dead particles.  相似文献   

18.
The results of measuring the total contents of carbon monoxide and methane via the method of solar-absorption spectroscopy are presented. The measurements were performed at the Molodezhnaya Station in 1977–1978, at the Mirny Observatory from 1982 to 1992, and at the Novolazarevskaya Station from 2003 to 2006. The character of seasonal variations in the contents of these gases in the Antarctic atmosphere is described and compared to the intra-annual variation of their surface concentrations measured at the Syowa Station (Japan). Synchronous intra-annual variations in the contents of carbon monoxide in the atmospheric column and in its surface concentrations are observed, while the spring maximum content of methane is observed three months after the maximum of its surface concentration. Synchronous seasonal variations in the total content of methane and ozone are observed, which makes it possible to suggest that the Antarctic circumpolar vortex has a significant influence on the characteristics of the vertical distribution of methane during Antarctic spring. Quantitative estimates of the parameters of multiyear variations in the contents of CO and CH4 are given. The content of methane was increasing (although with different rates) during the entire observation period 1977–2006. The content of CO was observed to increase until 1992 and to decrease during 2003–2006.  相似文献   

19.
Based on observations of carbon monoxide (CO) concentrations at three Mosekomonitoring stations, we have analyzed the weekly cycle of CO in the surface air of Moscow in 2004–2007. At all stations the minimum long-term mean daily CO values are observed on Sunday. The weekly cycle of CO more clearly manifests itself at the center of Moscow and becomes less clear closer to the outskirts. We have analyzed the reproducibility of the weekly cycle of CO from one year to another, the seasonal dependence, its specific features at different times of day, and the changes in the diurnal cycle of CO during the week. The factors responsible for specific features of the evolution of surface CO concentrations at different observation stations have been analyzed. The empirical probability density functions of CO concentrations on weekdays and at week- end are presented. The regularity of the occurrence of the weekend effect in CO has been investigated and the possible reasons for breaks in weekly cycles have been analyzed. The Kruskal-Wallis test was used to study the statistical significance of intraweek differences in surface CO contents.  相似文献   

20.
Variations in the concentrations of gaseous pollutants in the air basin of Moscow are statistically analyzed. The basic statistical characteristics of variations in the concentrations of carbon monoxide, nitric oxide, nitrogen dioxide, ozone, formaldehyde, and a number of aromatic compounds are calculated. The main properties of intradiurnal, synoptic, seasonal, and interannual variations in the concentrations of gaseous pollutants are described. The power spectral densities of variations in the concentrations of carbon monoxide and nitrogen oxides are analyzed. The contributions made by variations in the concentration of carbon monoxide on different time scales to the total variance are calculated. The effect of the atmospheric air polluted with carbon monoxide and nitrogen oxides on the ecological situation in the city is estimated. The probabilities of an excess over the single maximum allowable concentrations are determined for carbon monoxide and nitrogen oxides. The absorption of shortwave solar radiation by nitrogen dioxide in the atmospheric boundary layer is estimated.  相似文献   

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