Laboratory and Field Measurements of Methanol Fluxes

挥发性有机化合物（VOCs）在对流层化学中起着积极的作用，然而我们对它们的源和汇的分布以及驱动它们的环境因素的了解往往很少。甲醇是一种重要的含氧VOC，在对流层中无处不在，是全球奇数氢（HOx=OH+HO2）的来源。据认为，它主要作为植物生长过程中果胶脱甲基化的副产品排放到大气中，并主要通过与羟基自由基反应从大气中去除。这些和其他源和汇的相对贡献仍然不确定，需要进行广泛的实验室和实地测量，以提高我们的认识。我们建议有助于这些努力首先进行深入的实验室研究土壤交换的甲醇，一个潜在的重要，但很少研究的球员在甲醇预算，使用动态流量室监测使用非常敏感的甲醇测量技术开发和测试我们的实验室在不莱梅大学。我们还建议在欧洲北方的Kannenbruch油田观测点，在树冠层的上方、内部和下方观测甲醇。Kutsch来自Jena的MPI生物地球化学，使用松弛涡流累积（REA）方法，冠层内梯度和动态室。这种测量的组合是一个积极的步骤，进一步阐明甲醇预算已经开始在我们的实验室在不莱梅大学，并将加强我们的实验室的联系，通量测量社区。

Volatile organic compounds (VOCs) play an active role in tropospheric chemistry, however our knowledge concerning their distribution of sources and sinks and the environmental factors driving them is often sparse. Methanol is an important oxygenated VOC found ubiquitously in the troposphere, serving as a source of global odd hydrogen (HOx=OH+HO2). It is thought to be emitted to the atmosphere mainly as a by-product of pectin demethylation during plant growth and removed from the atmosphere primarily through reaction with the hydroxyl radical. Relative contributions from these and other sources and sinks remain uncertain and will require extensive laboratory and field measurements to improve our understanding. We propose to contribute to these endeavors first by performing an in-depth laboratory study of soil exchanges of methanol, a potentially important but seldom studied player in the methanol budget, using a dynamic flux chamber monitored using an extremely sensitive methanol measurement technique developed and tested by our laboratory at the University of Bremen. We also propose to observe methanol both above, within, and below the canopy of a northern European forest ecosystem at the Kannenbruch field site operated by Dr. W. Kutsch from the MPI for Biogeochemistry in Jena, using a relaxed eddy accumulation (REA) method, an in-canopy gradient, and dynamic chambers. This combination of measurements is a positive step towards further elucidation of the methanol budget already begun in our laboratory at the University of Bremen and will strengthen the ties of our laboratory to the flux measurement community.