...
【24h】

Nitric acid from volcanoes

机译:火山中的硝酸

获取原文
获取原文并翻译 | 示例
           

摘要

Atmospheric cycling of nitric acid and other nitrogen-bearing compounds is an important biogeochemical process, with significant implications for ecosystems and human health. Volcanoes are rarely considered as part of the global nitrogen cycle, but here we show that they release a previously unconsidered flux of HNO_3 vapour to the atmosphere. We report the first measurements of nitric acid vapour in the persistent plumes from four volcanoes: Masaya (Nicaragua); Etna (Italy); and Villarrica and Lascar (Chile). Mean near-source volcanic plume concentrations of HNO_3 range from 1.8 to 5.6 μmol m~(-3), an enrichment of one to two orders of magnitude over background (0.1-1.5 mol m~(-3)). Using mean molar HNO_3/SO_2 ratios of 0.01, 0.02, 0.05, and 0.07 for Villarrica, Masaya, Etna, and Lascar respectively, combined with SO_2 flux measurements, we calculate gaseous HNO_3 fluxes from each of these volcanic systems, and extend this to estimate the global flux from high-temperature, non-explosive volcanism to be ~0.02-0.06 Tg (N) yr~(-1). While comparatively small on the global scale, this flux could have important implications for regional fixed N budgets. The precise mechanism for the emission of this HNO_3 remains unclear but we suggest that thermal nitrogen fixation followed by rapid oxidation of the product NO is most likely. In explosive, ash-rich plumes NO may result from, or at least be supplemented by, production from volcanic lightning rather than thermal N fixation. We have calculated NO production via this route to be of the order of 0.02 Tg (N) yr~(-1).
机译:硝酸和其他含氮化合物的大气循环是重要的生物地球化学过程,对生态系统和人类健康具有重大影响。火山很少被认为是全球氮循环的一部分,但在这里我们证明了它们向大气释放了以前未考虑的HNO_3蒸气通量。我们报告了来自四个火山的持久羽状流中硝酸蒸气的首次测量:马萨亚(尼加拉瓜);埃特纳火山(意大利);以及比利亚里卡和拉斯卡(智利)。 HNO_3的近源火山羽平均浓度范围为1.8至5.6μmolm〜(-3),比本底液(0.1-1.5 mol m〜(-3))富集一到两个数量级。分别使用Villarrica,Masaya,Etna和Lascar的HNO_3 / SO_2摩尔平均比分别为0.01、0.02、0.05和0.07,并结合SO_2通量测量,我们从这些火山系统中的每一个计算出气态HNO_3通量,并将其扩展以估算来自高温,非爆炸性火山的总通量为〜0.02-0.06 Tg(N)yr〜(-1)。尽管在全球范围内相对较小,但这种变化可能会对区域固定N预算产生重要影响。释放这种HNO_3的确切机制尚不清楚,但我们建议最有可能进行热氮固结,然后迅速氧化产物NO。在爆炸性的,富含灰分的羽流中,NO可能是由火山闪电产生的,而不是由热固氮产生的,或者至少是由火山闪电产生的。我们计算出通过该途径产生的NO量约为0.02 Tg(N)yr〜(-1)。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号