The role of the ocean in the global atmospheric budget of acetone
The role of the ocean in the global atmospheric budget of acetone
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DOI：
10.1029/2011gl050086
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发表时间：
2012-01-13
影响因子：
5.2
通讯作者：
Mao, J.
中科院分区：
文献类型：
--
作者：
Fischer, E. V.;Jacob, D. J.;Mao, J.
丙酮是大气中含量最丰富的羰基化合物之一，在大气化学中起着重要的作用。海洋在全球大气丙酮预算中的作用是高度不确定的，过去的研究得出了相反的结论，即海洋是源还是汇。在这里，我们使用全球3-D化学输送模式(GEOS-Chem)模拟大气丙酮，以评估海-气交换在全球预算中的作用。模型中包含了更新的(较慢的)光解损失，这意味着不需要大量的净海洋源来解释海洋空气中观察到的丙酮。我们发现，基于观测的固定海水丙酮浓度为15 nm的模拟可以重现观测到的大气浓度和海气通量的全球模式。北半球海洋是丙酮的净汇，而热带海洋是丙酮的净来源。在全球范围内，海洋与大气处于接近平衡的状态。在模型中规定丙酮的海洋浓度作为边界条件，假设海洋浓度由内部生产和损失控制，而不是由气-海交换控制。这意味着海洋在控制大气层丙酮方面起着重要作用。这一假设需要通过更好地量化海洋丙酮源和汇来检验。引文：Fischer，E.V.，D.J.Jacob，D.B.Millet，R.M.Yantosa和J.Mao(2012)，海洋在丙酮全球大气预算中的作用，地球物理。研究报告，39，L01807，DOI：10.1029/2011GL050086。
Acetone is one of the most abundant carbonyl compounds in the atmosphere and it plays an important role in atmospheric chemistry. The role of the ocean in the global atmospheric acetone budget is highly uncertain, with past studies reaching opposite conclusions as to whether the ocean is a source or sink. Here we use a global 3-D chemical transport model (GEOS-Chem) simulation of atmospheric acetone to evaluate the role of air-sea exchange in the global budget. Inclusion of updated (slower) photolysis loss in the model means that a large net ocean source is not needed to explain observed acetone in marine air. We find that a simulation with a fixed seawater acetone concentration of 15 nM based on observations can reproduce the observed global patterns of atmospheric concentrations and air-sea fluxes. The Northern Hemisphere oceans are a net sink for acetone while the tropical oceans are a net source. On a global scale the ocean is in near-equilibrium with the atmosphere. Prescribing an ocean concentration of acetone as a boundary condition in the model assumes that ocean concentrations are controlled by internal production and loss, rather than by air-sea exchange. An implication is that the ocean plays a major role in controlling atmospheric acetone. This hypothesis needs to be tested by better quantification of oceanic acetone sources and sinks. Citation: Fischer, E. V., D. J. Jacob, D. B. Millet, R. M. Yantosca, and J. Mao (2012), The role of the ocean in the global atmospheric budget of acetone, Geophys. Res. Lett., 39, L01807, doi: 10.1029/2011GL050086.