Collaborative Research: Trace Gas Deposition Processes in the Arctic Boundary Layer

这项研究关注的是数据分析和建模活动，以获得对大气痕量气体动力学，特别是北极边界层臭氧的过程的进一步了解。这些研究活动将有助于提高对对流层臭氧和其他痕量气体的预测性认识，这些气体可对北极的化学和辐射平衡产生重大影响。本研究的目的是进一步了解微量气体沉积速率，并达到以下目的：1。研究估算北极大气表层痕量气体输送的最适当方法，2.评价电化学臭氧探测仪数据用于推算臭氧沉积率的适用性。根据在北极选定地点例行获得的臭氧探测仪，研究和量化北极选定地点的臭氧沉积率。并定义北极边界层发生最大臭氧表面沉积率时的大气条件。这些目标将通过数据分析和建模研究相结合来实现，采用三个被认为是高质量的数据集。2000年春季，我们在加拿大努纳武特阿勒特和丹麦格陵兰岛萨米特获得了高频数据。这两个数据集涉及塔和系留气球的垂直气象和化学剖面，将在调查最适当方法的框架内进行分析，以得出地面和上覆大气之间和/或反之亦然的痕量气体通量。这些活动的其他科学产出涉及与北极边界层痕量气体通量有关的湍流长度尺度。湍流尺度的知识是至关重要的，以了解大气层的影响，微量气体排放的北极积雪。第三个数据集涉及臭氧探测仪在整个北极选定地点发布的存档数据。我们将利用这些广泛的历史数据来开发一个一维模型，以获得臭氧沉积速率的积雪表面。估算的沉积率将提供上限阈值，然后可将其纳入区域和/或全球模型，以限制北极对流层的臭氧收支。这项研究将导致一个简单的建模参数化，以便根据世界气象组织（气象组织）的臭氧监测网络定期得出臭氧沉积率，从而为解释北极边界层臭氧时间变化的过程提供关键信息。了解臭氧动态对于确定臭氧在北极化学和辐射平衡中的作用至关重要。鉴于最近发现北极积雪是一氧化氮、二氧化氮、亚硝酸和甲醛等气体的重要来源，该项目还将产生根据环境（剖面）浓度推断这些重要痕量气体通量的方法。

This research is concerned with data analyses and modeling activities to gain further insights on the processes governing atmospheric trace gas dynamics, in particular ozone in the arctic boundary layer. The research activities will lead to improvements in the predictive understanding of tropospheric ozone and other trace gases, which can exert a critical influence in the arctic chemical and radiative balance. Our studies are motivated to derive further understanding of trace gas deposition rates and will achieve the following objectives:1. to investigate the most appropriate methods for estimating trace gas transport in the surface layer of the arctic atmosphere,2. to evaluate the suitability of electrochemical ozonesonde data for deriving ozone deposition rates,3. to study and quantify ozone deposition rates at selected Arctic sites based on ozonesonde routinely obtained at selected arctic sites,4. and to define the atmospheric conditions when maximum ozone surface deposition rates take place in the arctic boundary layer.These objectives will be addressed through a combination of data analyses and modeling studies employing three data sets deemed to be of high quality. During spring 2000, we obtained high frequency data at Alert, Nunavut, Canada and Summit, Greenland, Denmark. These two data sets, involving vertical meteorological and chemical profiles from towers and tethered balloons, will be analyzed within the framework of investigating the most appropriate methods to derive trace gas fluxes between the surface and overlying atmosphere and/or vice versa. Additional scientific outputs of these activities relate to the turbulent length scales associated with trace gas fluxes in the arctic boundary layer. Knowledge of turbulent scales is critically essential to understand the atmospheric layer impacted by trace gas emissions from the Arctic snowpack. The third data set involves the archived data from ozonesondes released at selected sites throughout the Arctic. We will employ these extensive historical data to develop a one-dimensional model to derive ozone deposition rates to the snowpack surface. Estimated deposition rates will provide upper threshold values that can then be incorporated in regional and/or global models to constrain ozone budgets in the arctic troposphere. The research will lead to a simple modeling parameterization to routinely derive ozone deposition rates based on the World Meteorological Organization (WMO) ozone monitoring network, and thus provide critical information to decipher the processes governing ozone temporal changes in the Arctic boundary layer. Understanding of ozone dynamics is crucial to define the contribution of ozone in the chemical and radiative balance of the Arctic. Given the recent discovery that the arctic snowpack represents a substantial source of gases such as nitric oxide, nitrogen dioxide, nitrous acid and formaldehyde, this project will also yield methodologies to deduce fluxes of these important trace gases based on ambient (profile) concentrations.