Atmospheric measurements of the carbon cycle

我的研究计划侧重于从大气角度研究碳循环。我的团队测量与碳循环相关的大气痕量气体，如二氧化碳(CO2)、甲烷(CH4)、一氧化碳(CO)和一氧化碳(OCS)，目的是量化陆地生物圈和城市排放的碳交换。我们的研究重点是改进大气测量本身，以及从这些测量中衍生出的科学。燃烧化石燃料释放的碳中约有一半留在大气中；另一半被海洋和陆地生物圈以大致相等的比例吸收。我们目前对全球碳循环的理解存在一个重大差距，那就是陆地生物圈在消除大气中的碳方面所起的作用，以及在气候变暖加剧的情况下它将发挥的作用。北美陆地生物圈在过去十年中一直是一个持续的净碳汇，但气候变化、土地利用变化和干扰对未来的影响尚不清楚。例如，加拿大的森林现在被认为是大气中的一小部分碳源。我的研究计划将开发新的大气测量工具，以更好地了解气候变量、野火和其他干扰对大气组成的影响，这反过来将为未来的变化提供更好的预测。众所周知，北美城市产生的二氧化碳排放量约占总排放量的80%，市政府已经组成了全球联盟来减少排放，速度往往快于联邦政府。人们对全球城市对CH4排放的贡献知之甚少，但它被认为是非常重要的。大多数城市使用库存来量化排放，这些排放是根据行业报告汇编的。这些清单对分析行业排放很有用，但它们不能考虑未知或无意的排放。因此，根据大气测量得出的排放量量化对于核实排放量很重要，但它们提供的关于确切排放源的详细信息较少。清单和大气量化一起提供了关于排放的最有力的政策相关信息。我的研究计划集中在大多伦多地区(GTA)，在那里我们已经开发了设施级的CH4排放清单，以及密集的地面大气观测站。我们将开发技术，用我们的大气测量来验证和改进我们的CH4清单，并使用这些技术来评估政策的有效性。我们将应用这些技术来量化GTA的二氧化碳排放量，并与市政府和其他利益相关者合作，将这种网络扩展到其他城市。

My research program focuses on the study of the carbon cycle from the atmospheric perspective. My group measures carbon cycle-relevant atmospheric trace gases, such as carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and carbonyl sulfide (OCS), with the goal of quantifying the exchange of carbon from the terrestrial biosphere and from urban emissions. Our research focuses on improving the atmospheric measurements themselves, and on the science derived from those measurements. About half of the carbon released by burning fossil fuels remains in the atmosphere; the other half is absorbed by the oceans and terrestrial biosphere in approximately equal proportion. A significant gap in our current understanding of the global carbon cycle is the role that the terrestrial biosphere plays in removing carbon from the atmosphere, and the role it will play under increased warming. The North American terrestrial biosphere has been a persistent net carbon sink over the past decade, but future impacts from climate change, land-use change, and disturbance are unclear. Canadian forests, for example, are now thought to be a small source of carbon to the atmosphere. My research program will develop new atmospheric measurement tools to better understand the impacts of climate variables, wildfires and other disturbance on atmospheric composition, which will in turn provide better predictions of future change. Cities are known to produce around 80% of North American CO2 emissions, and municipal governments have formed global coalitions to reduce their emissions, often faster than their federal counterparts. Less is known about the global urban contribution to CH4 emissions, but it is thought to be significant and important. Most cities use inventories to quantify emissions that are compiled from industry reports. These inventories are useful for analysing sectorial emissions, but they cannot account for emissions that are unknown or inadvertent. Therefore, emissions quantification derived from atmospheric measurements is important for verifying emissions, but they provide less detailed information about the precise source of the emission. Together, inventories and atmospheric quantification provide the most powerful policy-relevant information about emissions. My research program focuses on the Greater Toronto Area (GTA), where we have developed a facility-level CH4 emission inventory, and a dense ground-based atmospheric observatory. We will develop techniques for verifying and improving upon our CH4 inventory with our atmospheric measurements, using these techniques to evaluate policy efficacy. We will apply these techniques to quantify CO2 emissions from the GTA and engage municipal governments and other stakeholders to expand this kind of network to other cities.