Temporal and Spatial Variations of the Atmospheric Cycle of Carbonyl Sulphide

硫化羰大气循环的时空变化

• 批准号: NE/D00053X/1
• 负责人: Anthony Kettle
• 金额: $ 6.59万
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FD00053X%2F1
• 关键词: Temporal; Spatial; Variations; Atmospheric; Cycle

The atmosphere contains a number of trace gases that are important in controlling the energy budget and temperature at the Earth's surface. The greenhouse gases (of which carbon dioxide is perhaps the best-known example) act as a blanket to increase the surface temperatures. The presence of atmospheric aerosols acts to counter the warming effect of the greenhouse gases by reflecting sunlight back into space. The aerosols are produced mostly by the destruction of sulphur gases that are produced by human activities and natural processes. Most of these sulphur gases are short-lived and are destroyed to form aerosol particles in a few days. However, one of the sulfur gases - carbonyl sulphide (COS) - is stable in the lower atmosphere and is destroyed by the intense radiation and chemical processes in the stratosphere. This long-lived gas has the potential to perturb the surface radiation budget on longer time scales. Our proposed research is to understand the anthropogenic, biological, chemical, and physical transport processes that influence the distribution of COS in the atmosphere. Its concentration in the atmosphere is governed by the balance of a number of sources and sinks. The most important sources are human industrial activities, biomass burning, outgassing from the oceans, and production in raindrops. In addition to the stratospheric destruction process, additional sinks include uptake by vegetation and destruction by soils. Measurements of atmospheric concentrations over the last 50 years indicate that there has not been significant increases or decreases and that the sources and sinks nearly balance over this time frame. However, the measurements reveal that there is pronounced seasonal variation in the concentration, and that the seasonal trend is different in the Northern and Southern Hemispheres. This indicates that while the source and sinks are balanced on long time scales, they are out of balance at certain times of the year. The strengths of individual sources and sinks must vary over the course of a year to give the seasonal variability in atmospheric COS concentration, but it is not clear how. In addition, winds in the atmosphere spread COS from polluted to remote regions, and this also contributes to the observed variability in measured concentrations. The seasonal variation of the sources and sinks is not well-constrained, and the advection effect for COS has been investigated in only one previous study. Using a numerical model, we want to quantify the effect of each of the COS sources and sinks on the observed concentrations at different places in the world and at different times. To test the model predictions, we will look at measured concentration datasets from aircraft campaigns, firn air samples, and air sampling stations in different parts of the world. We hope to gain a better understanding of the atmospheric COS budget for the present day and to quantify the relative contribution of the anthropogenic and natural sources. We also want to understand how the strengths of the sources and sinks depend on anthropogenic activities both at the present time and in the past. Ice core measurements indicate that atmospheric COS concentrations 300 years ago were less than half of what they are at present. It is an important test for our understanding of the current COS budget that the numerical model will be able to duplicate this measured result for the pre-industrial atmosphere. In this case, we will have the confidence to predict future atmospheric COS concentrations and radiation effects in the increasing greenhouse world of the present century.

大气层中含有许多微量气体，这些气体对控制地球表面的能量收支和温度非常重要。温室气体（二氧化碳可能是最著名的例子）就像一层毯子，增加了地表温度。大气气溶胶的存在通过将阳光反射回太空来抵消温室气体的变暖效应。气溶胶主要是由人类活动和自然过程产生的含硫气体破坏而产生的。这些硫磺气体中的大多数是短暂的，在几天内被破坏形成气溶胶颗粒。然而，其中一种含硫气体-硫化羰（COS）-在低层大气中是稳定的，并被平流层中的强辐射和化学过程所破坏。这种长寿命的气体有可能在更长的时间尺度上扰动地表辐射收支。我们建议的研究是了解人为的，生物的，化学的和物理的传输过程，影响COS在大气中的分布。它在大气中的浓度取决于若干源和汇的平衡。最重要的来源是人类工业活动、生物质燃烧、海洋放气和雨滴生产。除了平流层的破坏过程外，其他汇包括植被的吸收和土壤的破坏。对过去50年大气浓度的测量表明，在这一时间范围内，浓度没有显著增加或减少，源和汇几乎达到平衡。然而，测量结果表明，浓度存在明显的季节变化，北方和南半球的季节趋势不同。这表明，虽然源和汇在长时间尺度上是平衡的，但在一年中的某些时候它们会失去平衡。各个源和汇的强度必须在一年中有所不同，才能给出大气COS浓度的季节性变化，但不清楚如何变化。此外，大气中的风将COS从污染地区传播到偏远地区，这也是观测到的测量浓度变化的原因之一。的源和汇的季节变化没有很好的约束，和对流效应COS已被调查，在以前的研究中只有一个。使用数值模型，我们想量化的COS源和汇的每一个在世界上不同的地方，在不同的时间观测到的浓度的影响。为了测试模型的预测，我们将研究来自世界各地的飞机活动，积雪空气样本和空气采样站的测量浓度数据集。我们希望能更好地了解目前大气中的COS预算，并量化人为和自然源的相对贡献。我们还想了解源和汇的强度如何取决于现在和过去的人类活动。冰芯测量表明，300年前大气中的COS浓度不到现在的一半。这是对我们理解当前COS预算的一个重要测试，数值模式将能够复制工业化前大气的测量结果。在这种情况下，我们将有信心预测未来的大气COS浓度和辐射效应在本世纪日益温室化的世界。

项目成果

How does the European eel ( Anguilla anguilla ) retain its population structure during its larval migration across the North Atlantic Ocean?

欧洲鳗鱼（Anguilla anguilla）在其幼体跨越北大西洋的迁徙过程中如何保持其种群结构？

• DOI: 10.1139/f05-198
• 发表时间: 2006
• 期刊: Canadian Journal of Fisheries and Aquatic Sciences
• 影响因子: 2.4
• 作者: Kettle A