Impact of Lightning on Air Chemistry and Climate
Impact of Lightning on Air Chemistry and Climate
复制标题
闪电对空气化学和气候的影响
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
V. Grewe
中科院分区：
文献类型：
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作者：
V. Grewe
这项研究表明，气候变化并不一定会导致闪电增加，因为研究将闪电与对流云顶高度联系起来，但可能会减少闪电。利用1960年至2020年的气候-化学耦合集合模式模拟结果，研究了闪电对空气化学和气候的影响。该模型模拟闪电和闪电引起的氮氧化物（NOx）的对流质量通量（上升气流速度）的基础上使用的参数化。计算的地球仪上的闪光频率分布与卫星观测结果基本一致，但某些海洋区域除外。结果显示，与一般预期不同，气候变暖时闪电活动减少。这种减少是因为较不频繁但较强的对流事件。因此，虽然个别事件会产生更多的闪电，但总的闪电频率会减少。计算减少闪电氮氧化物排放量的臭氧生产的氮氧化物的量，这首先导致增加闪电臭氧，直到20世纪70年代，然后减少的敏感性增加。在模拟过程中，气候在辐射强迫对臭氧变化的敏感性普遍降低。
The study shows that climate change does not necessarily lead to an increase in lightning as proposed by studies linking lightning to convective cloud top heights, but may reduce lightning. The impact of lightning on air chemistry and on climate is studied using simulation results obtained with a coupled ensemble climate-chemistry model from 1960 to 2020. The model simulates lightning and lightning induced nitrogen oxides (NOx) using a parameterisation based on the convective mass flux (updraft velocity). The computed flash frequency distribution over the globe is broadly in agreement with satellite observations, except for some oceanic regions. The results show, different from general expectations, a decrease in lightning activity in a warming climate. The decrease occurs because of less frequent though stronger convective events. Hence lightning decreases in total flash frequency, although individual events produce more lightning. The computed decrease in lightning NOx emissions is overlaid with an increase in sensitivity of ozone production to NOx amounts, which first leads to an increase in lightning ozone until the 1970s and then to a decrease. The sensitivity of climate in terms of radiative forcing to ozone changes is generally decreasing during the simulation.