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1.
《Comptes Rendus Geoscience》2018,350(7):403-409
The stratospheric ozone layer is expected to recover as a result of the regulations of the Montreal Protocol on chlorine and bromine containing ozone-depleting substances (ODSs). Model simulations project a return of global annually averaged total column ozone to 1980 levels before the middle of the 21st century, well before the ODSs will return to 1980 levels. This earlier ozone return date is due to the effects of rising greenhouse gas (GHG) concentrations. GHGs influence ozone directly by chemical reactions, but also indirectly by changing stratospheric temperature and the Brewer–Dobson circulation. Based on projections of chemistry–climate models, this article summarizes the effects of GHGs on stratospheric and total column ozone in the mid-latitude upper stratosphere, Arctic and Antarctic spring, and the tropics. The sensitivity of future ozone change to the GHG scenario is discussed, as well as the specific role of a future increase in nitrous oxide and methane. 相似文献
2.
《Comptes Rendus Geoscience》2018,350(7):384-392
The atmospheric observations of ozone-depleting substances (ODSs) have been essential for following their atmospheric response to the production and use restrictions imposed by the Montreal Protocol and its Amendments and Adjustments. ODSs have been used since the first half of the 20th century in industrial and domestic applications. However, their atmospheric growth went unnoticed until the early 1970s, when they were discovered using gas chromatograph-electron capture detection (GC-ECD) instruments. Similar instrumentation formed the basis of global flask and in situ measurements commenced by NOAA and ALE/GAGE/AGAGE in the late 1970s. The combination of these networks, supported by a number of other laboratories, has been essential for following the tropospheric trends of ODSs. Additionally, ground-based remote sensing measurements within NDACC and aircraft-based observation programs have been crucial for measuring the evolution of the ODS abundances over the entire atmosphere. Maintaining these networks at least at their current state is vital for ensuring the on-going verification of the success of the Montreal Protocol. 相似文献
3.
《Comptes Rendus Geoscience》2018,350(7):442-447
The Montreal Protocol has controlled the production and consumption of ozone-depleting substances (ODSs) since its signing in 1987. The levels of most of these ODSs are now declining in the atmosphere, and there are now initial signs that ozone levels are increasing in the stratosphere. Scientific challenges remain for the Montreal Protocol. The science community projected large ozone losses if ODSs continued to increase, and that ozone levels would increase if ODSs were controlled and their levels declined. Scientists remain accountable for these projections, while they continue to refine their scientific basis. The science community remains vigilant for emerging threats to the ozone layer and seeks scientific evidence that demonstrates compliance with Montreal Protocol. As ODSs decrease, the largest impact on stratospheric ozone by the end of the 21st century will be increases in greenhouse gases. The associated climate forcings, and the human responses to these forcings, represent major uncertainties for the future of the stratospheric ozone layer. 相似文献
4.
《Comptes Rendus Geoscience》2018,350(7):410-424
The Montreal Protocol has halted 99% of global production of chemical substances that deplete stratospheric ozone, which protects life on earth from the harmful effects of ultraviolet (UVB) radiation. UVB causes skin cancer and cataracts, suppresses the human immune system, destroys plastics, and damages agricultural crops and natural ecosystems. Because ozone-depleting substances (ODSs) are powerful greenhouse gases, the Montreal Protocol also protects climate. From the authors’ perspectives in multiple roles as environmental entrepreneurs, practitioners, and authorities, this paper explains how individuals, companies, and military organizations researched, developed, commercialized and implemented alternatives to ODSs that are also safer for climate. With the benefit of hindsight, the authors reflect on what was neglected or done badly under the Montreal Protocol and present lessons learned on how Montreal Protocol institutions can be renewed and revitalized to phase down hydrofluorocarbons (HFCs). 相似文献
5.
《Comptes Rendus Geoscience》2018,350(7):347-353
After the well-reported record loss of Arctic stratospheric ozone of up to 38% in the winter 2010–2011, further large depletion of 27% occurred in the winter 2015–2016. Record low winter polar vortex temperatures, below the threshold for ice polar stratospheric cloud (PSC) formation, persisted for one month in January 2016. This is the first observation of such an event and resulted in unprecedented dehydration/denitrification of the polar vortex. Although chemistry–climate models (CCMs) generally predict further cooling of the lower stratosphere with the increasing atmospheric concentrations of greenhouse gases (GHGs), significant differences are found between model results indicating relatively large uncertainties in the predictions. The link between stratospheric temperature and ozone loss is well understood and the observed relationship is well captured by chemical transport models (CTMs). However, the strong dynamical variability in the Arctic means that large ozone depletion events like those of 2010–2011 and 2015–2016 may still occur until the concentrations of ozone-depleting substances return to their 1960 values. It is thus likely that the stratospheric ozone recovery, currently anticipated for the mid-2030s, might be significantly delayed. Most important in order to predict the future evolution of Arctic ozone and to reduce the uncertainty of the timing for its recovery is to ensure continuation of high-quality ground-based and satellite ozone observations with special focus on monitoring the annual ozone loss during the Arctic winter. 相似文献
6.
Sophie Godin-Beekmann 《Comptes Rendus Geoscience》2010,342(4-5):339-348
This article provides an overview of the various satellite instruments, which have been used to observe stratospheric ozone and other chemical compounds playing a key role in stratospheric chemistry. It describes the various instruments that have been launched since the late 1970s for the measurement of total ozone column and ozone vertical profile, as well as the major satellite missions designed for the study of stratospheric chemistry. Since the discovery of the ozone hole in the early 1980s, spatial ozone measurements have been widely used to evaluate and quantify the spatial extension of polar ozone depletion and global ozone decreasing trends as a function of latitude and height. Validation and evaluation of satellite ozone data have been the subject of intense scientific activity, which was reported in the various ozone assessments of the state of the ozone layer published after the signature of the Montreal protocol. Major results, based on satellite observations for the study of ozone depletion at the global scale and chemical polar ozone loss, are provided. The use of satellite observations for the validation of chemistry climate models that simulate the recovery of the ozone layer and in data assimilation is also described. 相似文献
7.
《Comptes Rendus Geoscience》2018,350(7):376-383
Although catalytic chemistry involving ozone-depleting substances (ODSs) is currently a primary driver impacting the abundance of stratospheric ozone, water vapor and aerosols are constituents that also affect stratospheric ozone. Variability in both water vapor and aerosols can induce variability in ozone, and although small relative to that due to trends in ODSs, in the future may become a much more important source of ozone variability. 相似文献
8.
《Comptes Rendus Geoscience》2018,350(7):368-375
Thanks to the Montreal Protocol, the stratospheric concentrations of ozone-depleting chlorine and bromine have been declining since their peak in the late 1990s. Global ozone has responded: The substantial ozone decline observed since the 1960s ended in the late 1990s. Since then, ozone levels have remained low, but have not declined further. Now general ozone increases and a slow recovery of the ozone layer is expected. The clearest signs of increasing ozone, so far, are seen in the upper stratosphere and for total ozone columns above Antarctica in spring. These two regions had also seen the largest ozone depletions in the past. Total column ozone at most latitudes, however, does not show clear increases yet. This is not unexpected, because the removal of chlorine and bromine from the stratosphere is three to four times slower than their previous increase. Detecting significant increases in total column ozone, therefore, will require much more time than the detection of its previous decline. The search is complicated by variations in ozone that are not caused by declining chlorine or bromine, but are due, e.g., to transport changes in the global Brewer–Dobson circulation. Also, very accurate observations are necessary to detect the expected small increases. Nevertheless, observations and model simulations indicate that the stratosphere is on the path to ozone recovery. This recovery process will take many decades. As chlorine and bromine decline, other factors will become more important. These include climate change and its effects on stratospheric temperatures, changes in the Brewer–Dobson circulation (both due to increasing CO2), increasing emissions of trace gases like N2O, CH4, possibly large future increases of short-lived substances (like CCl2H2) from both natural and anthropogenic sources, and changes in tropospheric ozone. 相似文献
9.
《Comptes Rendus Geoscience》2018,350(7):432-434
NASA has a long and significant history in observations and data analysis research for understanding the short- and long-term changes in ozone in the atmosphere. For nearly 40 years, NASA has overseen satellite observations of stratospheric ozone. These observations have been augmented by ground-based remote sensing, balloon borne, and aircraft observations of ozone and ozone-related species and by continuous observations of ozone depleting substances. Together, they form the evidential basis for understanding ozone changes over these past four decades. Also, NASA has continuously funded laboratory, modeling and data analysis activities to better understand the observations obtained by NASA and other programs. NASA has plans to continue these activities in the future, at a level consistent with available funding, other Earth Science observational priorities, and more importantly, with a goal of ensuring that data exist to understand changes in ozone in the future as the abundances of ozone depleting substances decrease and those of greenhouse gases increase. 相似文献
10.
11.
Nandita D. Ganguly 《Journal of Earth System Science》2008,117(1):79-82
The Indian reserve of coking coal is mainly located in the Jharia coal field in Jharkhand. Although air pollution due to oxides
and dioxides of carbon, nitrogen and sulphur is reported to have increased in this area due to large-scale opencast mining
and coal fires, no significant study on the possible impact of coal fires on the stratospheric ozone concentration has been
reported so far. The possible impact of coal fires, which have been burning for more than 90 years on the current stratospheric
ozone concentration has been investigated using satellite based data obtained from Upper Atmospheric Research Satellite (UARS
MLS), Earth Observing System Microwave Limb Sounder (EOS MLS) and Ozone Monitoring Instrument (OMI) in this paper. The stratospheric
ozone values for the years 1992–2007, in the 28–36 km altitude range near Jharia and places to its north are found to be consistently
lower than those of places lying to its south (up to a radius of 1000 km around Jharia) by 4.0–20%. This low stratospheric
ozone level around Jharia is being observed and reported for the first time. However, due to lack of systematic ground-based
measurements of tropospheric ozone and vertical ozone profiles at Jharia and other far off places in different directions,
it is difficult to conclude strongly on the existence of a relationship between pollution from coal fires and stratospheric
ozone depletion. 相似文献
12.
《Comptes Rendus Geoscience》2018,350(7):341-346
The comprehensive investigation of polar ozone photochemistry and dynamics has required data obtained from as full a complement of available platforms as possible (ground-based, balloon, aircraft, and satellites). Perhaps the most detailed process studies have been conducted using measurements from aircraft, taking advantage of their targeting capabilities coupled with the potential for enabling measurements at high spatial and temporal resolution. The US National Aeronautics and Space Administration (NASA) conducted the first airborne science investigation of polar ozone in an effort to establish the causes of the recurring seasonal depletion of the Earth's stratospheric ozone layer over Antarctica that was identified in the mid-1980s. Subsequent airborne studies in the polar regions of both hemispheres benefitted from extensive successful collaborations among international scientists and the integration of the aircraft measurements with those obtained using ground-based, balloon-borne, and satellite instruments. This article provides an historical perspective of NASA's utilization of its airborne assets to advance our understanding of the chemical and physical processes that control the abundance of stratospheric ozone in both the Antarctic and Arctic. 相似文献
13.
S. Fadnavis S. Dhomse S. Ghude U. Iyer P. Buchunde S. Sonbawne P. E. Raj 《International Journal of Environmental Science and Technology》2014,11(2):529-542
Ozone trends in the Upper Troposphere and Lower Stratosphere over the Indian region are investigated using three satellite data sets namely Halogen Occultation Experiment (1993–2005), Stratospheric Aerosol and Gas Experiment (1993–2005) II, and Aura Microwave Limb Sounder (MLS, 2005–2011). Estimated ozone trends using multi-variate regression analysis are compared with trends at two Indian ozonesonde stations (Delhi, 28°N, 77°E and Pune, 18°N, 73°E), and a 3-D Chemical Transport Model (CTM, SLIMCAT) for the 1993–2005 time period. Overall, all the observational data sets and model simulations indicate significant increasing trend in the upper troposphere (0–2.5 %/year). In the lower stratosphere, estimated trends are slightly positive up to 30 mb and are negative between 30 and 10 mb. Increasing trends in the upper troposphere is probably due to increasing trends in the tropospheric ozone precursor gases (e.g. CO, NO x , NMHCs). Here, we argue that these contrasting ozone-trend profiles might be partially responsible for insignificant long-term trends in the tropical total column ozone. On seasonal scale, positive trends are observed during all the seasons in the upper troposphere while structure of trend profile varies in lower stratosphere. Seasonal variations of ozone trends and its linkages with stratospheric intrusions and increasing trends in lightning flashes in the troposphere are also discussed. 相似文献
14.
2008-2012年拉萨地基与卫星臭氧总量观测比较 总被引：1，自引：0，他引：1
通过比较2008-2012年拉萨站地基观测臭氧总量与三种卫星反演产品, 评估地基和卫星观测臭氧总量数据的质量信息. 结果表明: 地基与卫星臭氧总量绝对差为-10~15 DU, 相对差为-4%~4%, 日尺度相对差呈随机分布特征; TOSOMI算法反演的SCIAMACHY臭氧总量更接近地基观测结果, DOAS算法反演OMI臭氧总量与地基观测结果差异最大. 地基与卫星臭氧总量标准差存在季节性变化, 夏季最大, 冬季最小; 云的影响会加剧地基与卫星臭氧总量差异, 以SCIAMACHY产品最为显著. 相似文献
15.
16.
臭氧变化及其气候效应的研究进展 总被引：10，自引：0，他引：10
综述了近２０年来臭氧变化的规律和机制及其气候效应等领域的研究进展,指出对流层臭氧（主要在北半球）增加、平流层臭氧减少和臭氧总量减少是全球臭氧的变化趋势,原因主要是人类活动导致的ＮＯｘ、ＮＭＨＣ、ＣＯ、ＣＨ４等对流层臭氧前体物的增加和ＮＯｘ、Ｈ２Ｏ、Ｎ２Ｏ、ＣＦＣｓ等平流层臭氧损耗物质的增加。臭氧变化引起的气候效应表现在对流层臭氧的增加将带来地表和低层大气的升温,平流层臭氧的减少则可能导致地表和低层大气的升温或降温。将全球或区域气候模式和大气化学模式进行完全耦合来研究臭氧变化的气候效应是一种十分有效的手段,具有广阔的应用前景。 相似文献
17.
平流层爆发性增温中平流层环流及化学成分变化过程研究 总被引：3，自引：1，他引：2
利用欧洲中期天气预报中心（ECMWF）气象分析场、欧洲空间局ENVISAT/MIPAS卫星观测资料以及平/对流层大气化学输送模式MOZART 3综合分析了2003—2004年冬季北半球爆发性增温事件对于平流层大气环流、物质输送以及对流层顶附近臭氧通量等多方面的影响。结果表明：①本次增温过程持续时间长、强度大,平流层极涡从高层向下逐层分裂,增温效应作用到大气较低层,当纬向东风形成并维持后极涡又自上向下逐层恢复;②SSW过程前后行星波活动频繁,有长时间多次的上传,且以1波作用为主,2波对其进行补充;③在θ PVLAT坐标中分析发现SSW扰动过程中平流层中存在一对向极、向下的传播模态,相应的对流层中有一向赤道的传播模态,不同符号的纬向风、温度异常信号沿这两个模态传播,且上、下层传播模态在时间上存在着一定的联系;④增温过程中行星波活动引起的向极输送以及极区垂直运动的变化,共同影响了平流层的物质输送过程,从而导致北半球平流层N2O、O3、CH4、H2O等微量气体成分的垂直、水平分布发生显著变化;⑤增温过程中活跃的行星波可以造成平流层Brewer Dobson环流增强,同时导致高纬度地区（60~90°N）穿越对流层顶的臭氧通量（Cross Tropopause Ozone Flux, CTOF）显著增强,与行星波相联系的等熵物质运动引起“middleworld”区域内向赤道的臭氧通量也有所增强。 相似文献
18.
全球大气臭氧层的主要特征和变化趋势 总被引：8，自引：1，他引：8
根据全球臭氧地面站（Ｄｏｂｓｏｎ站、Ｂｒｅｗｅｒ站、Ｍ８３和Ｍ１２４ａｌ）总量资料、臭氧探空廓线资料和雨云卫星（ＴＯＭＳ、ＳＡＧＥⅠｆｏＳＡＧＥⅡ）臭氧总量和廓线资料，给出南、北半球特别是南极地区平流层臭氧主要特征和变化趋势。结果表明，无论是中、低纬地区还是高纬地区（特别是南极地区的“臭氧洞”）臭氧总工从７０年代开始呈下降趋势，特别是近十几年来有加剧下降之势，这是各国政府和科学家极为关注的环境和气候问题。此外，还对臭氧总量变化趋势的各种解释作了综述。 相似文献
19.
Ozone depletion at mid-latitudes is caused by reactivehalogens from man-made halocarbons. The stratosphericsulphate aerosol which follows large volcaniceruptions enhances (multiplies) this ozone depletion(it has no effect on ozone without halocarbons). Mid-latitude depletion almost doubled for the twoyears after Mt. Pinatubo. Although the MontrealProtocol is expected to reduce atmospheric amounts ofhalocarbons in the 21st century, stratospheric ozonewill be at risk of depletion enhancement by largeeruptions for the next 50 years. Mechanisms ofvolcanoes suggest that large eruptions are random andthat their global rate is constant for severalcenturies. Measurements of large eruptions during thelast 1000 years in ice cores have a remarkable fit toa Poisson distribution, reinforcing the conclusionthat the global incidence is random and at a constantrate for this period. From this rate, the probabilityof one or more eruptions with at least the ozone-lossenhancement of Pinatubo is 58 % in 50 years. Thisprobability is large enough to be of serious concernfor future mid-latitude ozone loss. 相似文献
20.
《Atmósfera》2014,27(3):251-260
Using satellite measurements from the Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI) version 8, this work presents the total column ozone (TCO) trends over Mexico and, in particular, over the state of Zacatecas. Interannual variations and their statistical dispersion show a surprisingly systematic behavior. Yearly low values occur during December and January, while high values between April and May. A significant depletion of about 2.5% in TCO between 1978 and 1994 is derived from their statistical analysis, which also shows stabilization from 1996 to 2013. Although the depletion is merely significant, it is a sign that the studied regions, crossed by the Tropic of Cancer, have not escaped to the depletion of the ozone layer. The characterization described herein is important in terms of the correlation of TCO and ultraviolet radiation levels. 相似文献