A SIMPLE, INEXPENSIVE, LIGHT WEIGHT, ROBUST AEROSOL OPTICAL SCATTER CELL.

简单、便宜、重量轻、坚固的气溶胶光学散射池。

• 批准号: NE/H00209X/1
• 负责人: Barbara Brooks
• 金额: $ 12.89万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FH00209X%2F1
• 关键词: SIMPLE; INEXPENSIVE; LIGHT; WEIGHT; ROBUST

The Intergovernmental Panel on Climate Change, in its fourth assessment report in 2007, states that anthropogenic aerosols 'remain the dominant uncertainty in radiative forcing'. More aerosols should reflect more sunlight out to space and tend to cool the climate, or alternatively, if the aerosols contain black carbon they may heat the air and cause clouds to evaporate, and less cloud would reflect less sunlight to space. More aerosols could lead to clouds having more but smaller water cloud droplets so they would appear 'whiter' and reflect more sunshine back to space, in addition, if the smaller droplets are less likely to coalesce and form rain and dissipate, so the cloud lifetime may increase. For ice clouds the situation is even more complex and uncertain. When the temperature falls below freezing most of the water drops remain as liquid and are 'supercooled'; only a very few aerosol particles have the property of being an 'ice nuclei' and promoting freezing. The effect of anthropogenic aerosols on the number of ice nuclei is essentially unknown. In addition aerosols themselves can be composed of pollutants which are deleterious to health, and so we need to know more about their sources, how they are transported around the atmosphere and how they are removed from the air, if we are to understand and consequently improve models forecasting pollution levels. To improve our knowledge of aerosols in the atmosphere we need better measurements of their distribution and how this changes as a function of the different weather patterns and how the aerosols influence the cloud properties. In particular we need to be able to make measurements form a wide range of platforms and in extreme conditions: for example close to sea surface in high wind conditions. Although the range of instrumentation available is wide those with a temporal response suitable for the investigation of particle fluxes (~10Hz) are too large and expensive, while those with a smaller foot print are again expensive and have too slow a temporal response. To address these problems researchers at the University of Leeds developed a small, light weight, fast response optical spectrometer, CLASP, and its participation in a wide variety of projects is tantamount to it success and popularity. Use had to be made, however, of a commercially available scatter cell that has proven overly complex with components used in its fabrication that are now obsolete; in addition the punitive licence agreement required form the manufacturer means that no further cell development can occur and the increasing number of requests to purchase a CLASP unit refused. The team that originally developed CLASP have been working on a new and vastly improved scatter cell from which a new generation of fast response, small, light weight aerosol spectrometers can be developed to address the need for instrumentation that can be used in extreme deployment scenarios, in personal samplers, or on platforms where size and weight is an issue. This new cell is currently at Technology Readiness Level (TRL) 3 and funding is requested to progress this cell to TRL 4 and beyond.

政府间气候变化专门委员会在 2007 年的第四次评估报告中指出，人为气溶胶“仍然是辐射强迫的主要不确定因素”。更多的气溶胶应该将更多的阳光反射到太空，从而使气候变冷，或者，如果气溶胶中含有黑碳，它们可能会加热空气并导致云层蒸发，而较少的云层则会将更少的阳光反射到太空。更多的气溶胶可能会导致云层中含有更多但更小的水云滴，因此它们会显得“更白”并将更多的阳光反射回太空，此外，如果较小的水滴不太可能聚结并形成雨和消散，那么云的寿命可能会增加。对于冰云来说，情况更加复杂和不确定。当温度降至冰点以下时，大部分水滴仍保持液态并处于“过冷”状态；只有极少数气溶胶颗粒具有成为“冰核”并促进冻结的特性。人为气溶胶对冰核数量的影响基本上是未知的。此外，气溶胶本身可能由对健康有害的污染物组成，因此，如果我们要了解并改进预测污染水平的模型，我们需要更多地了解其来源、它们如何在大气中传播以及如何从空气中去除。为了提高我们对大气中气溶胶的了解，我们需要更好地测量它们的分布，以及气溶胶如何随不同天气模式而变化，以及气溶胶如何影响云特性。特别是，我们需要能够在各种平台和极端条件下进行测量：例如在强风条件下靠近海面。尽管可用的仪器范围很广，但那些具有适合研究粒子通量（~10Hz）的时间响应的仪器太大且昂贵，而那些具有较小占地面积的仪器又昂贵且时间响应太慢。为了解决这些问题，利兹大学的研究人员开发了一种小型、轻量、快速响应的光学光谱仪，CLASP，它参与了各种各样的项目就等于它的成功和普及。然而，必须使用市售的散射池，事实证明这种散射池过于复杂，其制造中使用的组件现已过时；此外，制造商要求的惩罚性许可协议意味着无法进行进一步的电池开发，并且越来越多的购买 CLASP 装置的请求被拒绝。最初开发 CLASP 的团队一直致力于开发一种经过大幅改进的新型散射单元，利用该散射单元可以开发出新一代快速响应、小型、轻量的气溶胶光谱仪，以满足对可用于极端部署场景、个人采样器或尺寸和重量存在问题的平台上的仪器的需求。该新单元目前处于技术就绪级别 (TRL) 3，需要资金来将该单元提升至 TRL 4 及更高级别。