Changes in CH4 and CO growth rates after the eruption of Mt Pinatubo and their link with changes in tropical tropospheric UV flux
Changes in CH4 and CO growth rates after the eruption of Mt Pinatubo and their link with changes in tropical tropospheric UV flux
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DOI：
10.1029/96gl02638
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发表时间：
1996-10-01
影响因子：
5.2
通讯作者：
Madronich, S
中科院分区：
文献类型：
--
作者：
Dlugokencky, EJ;Dutton, EG;Madronich, S
每周在全球分布的采样点网络收集的空气样本的痕量气体测量表明，热带和南部高纬度地区甲烷和一氧化碳的生长命运在火山喷发后立即急剧增加。1991年6月15日，皮纳图博。这次喷发向平流层下部排放了大约20Mt的二氧化硫。用辐射传输模式计算表明，由于SO2的直接吸收，290-330 nm波段的UV光化通量在喷发后立即衰减了约12%，而由于硫酸盐气溶胶的散射，喷发后UV光化通量被扰动了长达1年之久。我们认为，减少的紫外光通量降低了稳态的[OH]，并导致了在1991年底和1992年初观察到的CH4和CO的异常大的增长率。
Trace gas measurements from air samples collected weekly at a globally distributed network of sampling sites revealed sharp increases in the growth Fates of CH4 and CO in the tropics and high southern latitudes immediately following the eruption of Mt. Pinatubo on June 15, 1991. The eruption emitted similar to 20 Mt SO2 into the lower stratosphere. Calculations made with a radiative transfer model show that UV actinic flux in the wavelength region 290-330 nm was attenuated by similar to 12% immediately after the eruption due to direct absorption by SO2, and that it was perturbed for up to 1 year after the eruption due to scattering by sulfate aerosols. We suggest that the decreased UV flux decreased the Steady-state [OH] and led to the observed anomalously large growth rates for CH4 and CO during late-1991 and early-1992.