South American Biomass Burning Analysis (SAMBBA)

生物质燃烧气溶胶（BBA）对区域辐射收支具有相当大的影响，因为它显著地扰动了地表通量和大气加热速率，其CCN特性扰动了云微物理，从而影响云的辐射特性、降水和云寿命。除了气候变化之外，对升温速率和CCN的如此大的影响很可能还会影响区域天气预报。人们日益认识到，生物质燃烧影响生物圈，但影响的程度需要量化。然而，由于黑碳与有机和无机物质的混合，BBA是一种复杂且鲜为人知的气溶胶物种。此外，排放率难以量化，难以在模型中表示。随着测量方法和模型能力在过去几年中迅速发展，现在已经足够先进，BBA的过程和性质可以充分受到测量的限制，现在是时候解决这些挑战了；这些可以用来挑战数值天气预报（NWP）和气候模式中使用的新的气溶胶方案。亚马逊地区是世界上最重要的生物质燃烧地区之一，在干旱季节受到强烈生物质燃烧的严重影响，导致高度浑浊的条件，因此是量化这些过程和确定这些相互作用对该地区天气和气候影响的关键环境。虽然以前对亚马逊地区的BBA及其辐射影响进行了大规模的研究，但这些研究已经有十多年的历史了，鉴于近年来模型和测量的快速发展，可以在解决上述所有问题方面取得相当大的科学进展。因此，我们提出了一个主要的联盟项目SAMBBA，这是一个由7所大学合作伙伴和英国气象局组成的联盟，它将提供一套亚马逊BBA的地面、飞机和卫星测量数据，并利用这些数据来1)提高我们对BB排放的认识；2)挑战和改进最新的气溶胶过程模型；3)挑战和改进卫星检索；4)利用具有广泛气溶胶预测方案的下一代气候模式和NWP模式对亚马逊河流域及周边地区的区域气候和天气影响进行试验预测；5)评估…的影响。亚马逊生物圈上的生物质燃烧。主要的实地试验将于2012年9月在巴西波尔图韦罗进行。每年的这个时候，整个地区都会发生大面积的燃烧，导致高度浑浊的情况。英国大型研究飞机（FAAM）将用于采样气溶胶的化学、物理和光学性质以及气相前体浓度。还将利用飞机上的先进辐射计测量辐射，并利用卫星数据。生物质燃烧气溶胶的影响在当地、天气、季节和气候时间尺度上非常显著，因此需要使用层次模型来建立和测试关键过程并量化影响。我们将利用SAMBBA期间进行的新的、全面的观测来挑战那些对生物质燃烧气溶胶进行详细过程描述的模型，以评估模型的性能并改进参数化。数值天气预报和具有一定复杂性和空间分辨率的气候模式模拟将用于研究吸收气溶胶可能在区域和更广泛尺度上影响动力学和气候的方式。该方法的核心是使用一系列新的模型，这些模型可以利用气溶胶和云的耦合描述来研究这种相互作用，从而充分研究空间尺度上的反馈，这些反馈已经得到充分的解决，可以评估这种过程。

Biomass burning aerosol (BBA) exerts a considerable impact on regional radiation budgets as it significantly perturbs the surface fluxes and atmospheric heating rates and its CCN properties perturb cloud microphysics and hence affect cloud radiative properties, precipitation and cloud lifetime. It is likely that such large influences on heating rates and CCN will affect regional weather predictions in addition to climatic changes. It is increasingly recognised that biomass burning affects the biosphere but the magnitude of the effects need to quantified. However, BBA is a complex and poorly understood aerosol species because of the mixing of the black carbon with organic and inorganic species. Furthermore, emission rates are poorly quantified and difficult to represent in models. It is now timely to address these challenges as both measurement methods and model capabilities have developed rapidly over the last few years and are now sufficiently advanced that the processes and properties of BBA can be sufficiently constrained by measurements; these can be used to challenge the new aerosol schemes used in numerical weather prediction (NWP) and climate models. Amazonia is one of the most important biomass burning regions in the world, being significantly impacted by intense biomass burning during the dry season leading to highly turbid conditions, and is therefore a key environment for quantifying these processes and determining the influence of these interactions on the weather and climate of the region. Though previous large scale studies of BBA over Amazonia and its radiative impacts have been performed, these are now over a decade old and considerable scientific progress can be made towards addressing all of the above questions given the rapid advance of models and measurements in recent years. We are therefore proposing a major consortium programme, SAMBBA, a consortium of 7 university partners and the UK Met Office, which will deliver a suite of ground, aircraft and satellite measurements of Amazonian BBA and use this data to 1) improve our knowledge of BB emissions; 2) challenge and improve the latest aerosol process models; 3) challenge and improve satellite retrievals; 4) test predictions of aerosol influences on regional climate and weather over Amazonia and the surrounding regions made using the next generation of climate and NWP models with extensive prognostic aerosol schemes; and 5) assess the impact of .biomass burning on the Amazonian biosphere. The main field experiment will take place during September 2012 and is based in Porto Vehlo, Brazil. At this time of year, widespread burning takes place across the region leading to highly turbid conditions. The UK large research aircraft (FAAM) will be used to sample aerosol chemical, physical and optical properties and gas phase precursor concentrations. Measurements of radiation will also be made using advanced radiometers on board the aircraft and satellite data will also be utilised. The influences of biomass burning aerosols are highly significant at local, weather, seasonal, and climate temporal scales necessitating the use of a hierarchy of models to establish and test key processes and quantify impacts. We will challenge models carrying detailed process descriptions of biomass burning aerosols with the new, comprehensive observations being made during SAMBBA to evaluate model performance and to improve parameterisations. Numerical Weather Prediction and Climate model simulations with a range of complexity and spatial resolution will be used to investigate the ways in which absorbing aerosol may influence dynamics and climate on regional and wider scales. At the heart of the approach is the use of a new range of models that can investigate such interactions using coupled descriptions of aerosols and clouds to fully investigate feedbacks at spatial scales that are sufficiently well resolved to assess such processes.