Trace gas emissions from Amazonia influence secondary organic aerosol (CLAIRE-UK)

南美洲的亚马逊热带雨林是目前世界上面临巨大压力的一个地区。在该地区经济增长的推动下，森林砍伐仍在继续，这导致原始森林转为农业，并导致影响该地区化学成分和污染的大火。与此同时，最新一代的气候模型表明，气候变化将对该地区产生巨大影响，随着该地区水平衡的变化，亚马逊雨林正面临干涸的威胁。这不仅对该地区本身产生重要影响。通过气候系统中所谓的遥相关，亚马逊雨林功能的变化与地球上其他地方的气候变化有关。亚马逊雨林不仅将大量的水和能量输送回大气，从而影响气候，而且还释放出大量的挥发性有机化合物，可能还有氨，它们在大气中发生反应，导致氧化剂和颗粒的产生。这些粒子为云滴的形成提供凝结核，云滴的形成调节了该地区的降水模式，改变了天气，从而反馈到排放上。然而，目前对排放和颗粒形成机制知之甚少。需要了解该地区当前的排放和空气化学及其对气象驱动因素变化的响应，以便在气候模式中将这些过程参数化，以提高未来气候预测的准确性。亚马逊大型生物圈-大气实验研究项目（LBA）先前的测量表明，如果可以避免生物质燃烧的影响，亚马逊偏远地区的空气化学是地球上受干扰最小的地区之一。因此，我们仍然有机会在一个相当不受干扰的环境中研究微量气体和气溶胶的循环，它们对区域气候的影响以及它们对气候驱动因素的响应。这个拟议的项目旨在将英国的测量增加到两个主要的国际野外活动中，在偏远的亚马逊雨林中与多达15个合作机构一起量化微量气体和气溶胶的排放及其控制，并研究树冠内部和树冠上方的化学相互作用，重点是量化颗粒产生。这些测量结果将用于提高我们在这个世界重要地区对空气污染物的化学和运输进行数值模拟的能力。

The Amazonian tropical rainforest in South America is an area of the world which is receiving significant pressures at present. Driven by economical growth in the region, deforestation is ongoing, which leads to conversion of primary forest for agriculture and large fires affecting the chemical composition and pollution in the region. At the same time, the most recent generation of climate models suggest that climate change will have dramatic consequences in the region and that the Amazonian rainforest is threatened by drying out as the water balance in the region changes. This not only has important consequences for the region itself. Through so-called teleconnection in the climate system, changes in the functioning of the Amazon rainforest is linked to changes in climate elsewhere on the planet. The Amazon rainforest does not just transport large amounts of water and energy back into the atmosphere, which affect the climate, it also emits large quantities of volatile organic compounds and, probably, ammonia, which react in the atmosphere, leading to the production of oxidants and particles. These particles provide the condensation nuclei for cloud droplet formation which regulate precipitation patterns in the region, change the weather and thus feed back onto the emissions. However, emissions and particle formation mechanisms are currently poorly understood. An understanding of the current emission and air chemistry in the region and its response to changes in meteorological drivers is needed to parametrise these processes in climate models to improve the rebustness of future climate predictions. Previous measurements with the research programme Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) have indicated that the air chemistry in remote regions of the Amazon is one of the least disturbed on the planet, if influences of biomass burning can be avoided. Thus we still have the chance to study the cycling of trace gases and aerosols, their effect on the regional climate and their responses to climatic drivers in a fairly undisturbed environment. This proposed project aims to add UK measurements to two major international field campaigns with up to 15 partner institutes in the remote Amazon rainforest to quantify the emissions of trace gases and aerosols, and their controls, and to study the chemical interactions within and above the tree canopy, with emphasis on the quantification of particle production. The measurements will be used to improve our capability to numerically simulate chemistry and transport of air pollutants in this important region of the world.