Study of an Arctic blowing snow-induced bromine explosion event in Ny-Ålesund, Svalbard.
Study of an Arctic blowing snow-induced bromine explosion event in Ny-Ålesund, Svalbard.
复制标题
对斯瓦尔巴群岛尼勒松的北极吹雪引起的溴爆炸事件的研究。
DOI：
10.1016/j.scitotenv.2022.156335
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Chen D
中科院分区：
文献类型：
--
作者：
Chen D
溴爆炸事件（BEE）是影响大气氧化能力的重要过程，特别是春季在极地对流层。尽管海冰表面被认为是溴的重要来源，但溴的释放机制仍不清楚。对活性溴（如BrO）进行高分辨率地面观测，对于评估对对流层臭氧的潜在影响和评价化学模型非常重要。然而，以前的模式研究很少关注斯瓦尔巴特群岛，这是由开放的海洋和海冰包围。在本文中，我们介绍了2017年3月在纽约州（78.92°N，11.93°E）部署的多轴差分光学吸收光谱仪得出的连续BrO倾斜柱密度和垂直柱密度。我们聚焦于3月中旬的一次BEE，在此期间，BrO的垂直柱密度从4.26 × 1013分子cm− 2飙升至3月17日的峰值1.23 × 1014分子cm− 2，表面臭氧从46.25 ppbv的背景水平减少到13.9 ppbv。这个案例研究表明，BEE与3月14日至18日接近斯瓦尔巴群岛的气旋系统引起的吹雪密切相关。通过考虑气象条件，海冰覆盖，和气团轨迹的历史，我们证明，海盐气溶胶（SSA）从吹雪海冰，而不是从开放的海洋，是由于这种BEE的发生。从一个平行的对流层离线模式的化学和运输（p-TOMCAT）的模式结果表明，这BEE主要是由一个吹雪事件与低压气旋系统触发。在高风速下，当气团通过海冰覆盖区时，由吹雪产生的SSA浓度达到最大值，这是导致Ny-Allesund溴爆炸过程的一个关键因素。由于分辨率较低，SSA释放溴的时间可能会延迟，模型与数据之间的差异仍然存在。
Bromine explosion events (BEEs) are important processes that influence the atmospheric oxidation capacity, especially in the polar troposphere during spring. Although sea ice surface is thought to be a significant bromine source, bromine release mechanisms remain unclear. High-resolution ground-based observations of reactive bromine, such as BrO, are important for assessing the potential impacts on tropospheric ozone and evaluating chemical models. However, previous model studies paid little attention to Svalbard, which is surrounded by both open ocean and sea ice. In this paper, we present continuous BrO slant column densities and vertical column densities derived by Multi-Axis Differential Optical Absorption Spectroscopy deployed at Ny-Ålesund (78.92°N, 11.93°E) in March 2017. We focused on one BEE in mid-March, during which the vertical column densities of BrO surged from 4.26 × 1013molecular cm−2to the peak at 1.23 × 1014molecular cm−2on March 17, surface ozone depleted from a background level of 46.25 parts per billion by volume (ppbv) to 13.9 ppbv. This case study indicates that the BEE was strongly associated with blowing snow induced by the cyclone systems that approached Svalbard from March 14 to 18. By considering meteorological conditions, sea ice coverage, and airmass trajectory history, we demonstrate that sea salt aerosols (SSAs) from blowing snow on sea ice, rather than from open ocean, are attributed to the occurrence of this BEE. Model results from a parallelized-tropospheric offline model of chemistry and transport (p-TOMCAT) indicate that this BEE was mainly triggered by a blowing snow event associated with a low-pressure cyclone system. The concentration of blowing-snow-sourced SSAs surged to peak when the airmass pass across the sea-ice-covered area under high wind speed, which is a critical factor in the process of bromine explosion observed in Ny-Ålesund. Due to the coarse resolution, the possible delayed timing of bromine release from SSA and the model-data discrepancies still exist.