Quantifying the impact of atmospheric aerosol on diffuse radiation and the Amazon biosphere

量化大气气溶胶对漫射辐射和亚马逊生物圈的影响

基本信息

批准号：
NE/J004723/1
负责人：
Dominick Spracklen
金额：
$ 10.19万
依托单位：
University of Leeds
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2012
资助国家：
英国
起止时间：
2012 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FJ004723%2F1
关键词：
Quantifying impact atmospheric aerosol diffuse

项目摘要

Trees in the Amazon are getting bigger absorbing large amounts of carbon dioxide from the atmosphere; equivalent to almost 10% of anthropogenic greenhouse gas emissions. This "carbon sink" slows the buildup of atmospheric carbon dioxide and therefore plays an important role in regulating climate change. At the moment we do not understand why the Amazon forest is behaving in this way. One potential reason is changes to the amount of tiny particles in the atmosphere called aerosols. We know that human activity has significantly changed the amount of aerosol over the Amazon: each dry season, humans start forest fires across southern parts of the Amazon basin (the so called "Arc of deforestation"). These fires emit large quantities of smoke aerosol into the atmosphere, scattering and absorbing radiation from the sun. This scattering of the sun's rays decreases the amount of direct radiation reaching the surface but increases the amount of diffuse radiation. It has been known for a long time that increases in diffuse radiation can increase plant productivity. For example, gardeners place "diffuser sheets" inside greenhouses that increase diffuse radiation in the similar way to atmospheric particles. The reason why diffuse radiation increases plant productivity is that it penetrates deeper into the canopy and illuminates leaves that would otherwise be in the shade. These previously shaded leaves can do more photosynthesis. A recent study showed that this effect can be very important, increasing the amount of carbon taken up by forests globally by 25%. It is therefore likely that deforestation fires (a major source of carbon dioxide emissions) are at least partly contributing to the sink of carbon dioxide in undisturbed forests in the Amazon basin. So far this effect has not been carefully studied for forests in the Amazon. Firstly, it is not well known exactly how much the amount of aerosol particles over the Amazon has changed. Second, no one has quantified how this change in aerosol particles has altered the amount of diffuse radiation. And finally we do not know whether these changes in diffuse radiation are sufficient to explain any of the observed changes in forest biomass across the Amazon. In this project we will use a suite of atmospheric aerosol, radiation and land-surface models to explore the problem. We will use a global model of atmospheric aerosol to simulate how aerosol distributions have changed over the Amazon over the last few decades. We will input these changes in aerosol into an atmospheric radiation model to quantify how amounts of diffuse radiation have changed. Finally, we will use these changes in diffuse radiation as input to a land-surface model to quantify how it impacts Amazon forests. At each step in the process we will use observations from ground-sites and satellite sensors to test how well the models explain observed changes. The project will lead to a much better understanding of how Amazon aerosol has changed and how this impacts diffuse radiation and the biosphere.

亚马逊地区的树木正在变得越来越大，从大气中吸收了大量的二氧化碳；相当于人为温室气体排放量的近10%。这种“碳汇”减缓了大气中二氧化碳的积累，因此在调节气候变化方面发挥着重要作用。目前我们不明白为什么亚马逊森林会这样。一个潜在的原因是大气中称为气溶胶的微小颗粒数量的变化。我们知道，人类活动显着改变了亚马逊上空的气溶胶含量：每个旱季，人类都会在亚马逊盆地南部地区引发森林火灾（所谓的“森林砍伐弧”）。这些火灾向大气中排放大量烟雾气溶胶，散射并吸收来自太阳的辐射。太阳光线的这种散射减少了到达表面的直接辐射量，但增加了漫射辐射量。人们很早就知道，增加漫射辐射可以提高植物生产力。例如，园丁在温室内放置“漫射片”，以与大气颗粒类似的方式增加漫射辐射。漫射辐射之所以能提高植物生产力，是因为它能深入树冠并照亮原本处于阴凉处的叶子。这些先前遮荫的叶子可以进行更多的光合作用。最近的一项研究表明，这种影响非常重要，使全球森林吸收的碳量增加了 25%。因此，森林砍伐火灾（二氧化碳排放的主要来源）可能至少部分促成了亚马逊盆地未受干扰森林的二氧化碳吸收。到目前为止，尚未对亚马逊森林的这种影响进行仔细研究。首先，目前尚不清楚亚马逊上空气溶胶颗粒的数量到底发生了多大变化。其次，没有人量化气溶胶颗粒的这种变化如何改变漫射辐射量。最后，我们不知道漫射辐射的这些变化是否足以解释观察到的亚马逊森林生物量的任何变化。在这个项目中，我们将使用一套大气气溶胶、辐射和地表模型来探索这个问题。我们将使用大气气溶胶的全球模型来模拟过去几十年亚马逊地区气溶胶分布的变化。我们将把气溶胶的这些变化输入到大气辐射模型中，以量化漫射辐射量的变化。最后，我们将使用漫射辐射的这些变化作为地表模型的输入，以量化其对亚马逊森林的影响。在该过程的每个步骤中，我们将使用地面站点和卫星传感器的观测结果来测试模型解释观测到的变化的程度。该项目将使人们更好地了解亚马逊气溶胶如何变化以及它如何影响扩散辐射和生物圈。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Extending water vapor trend observations over Boulder into the tropopause region: Trend uncertainties and resulting radiative forcing.

将博尔德上空的水汽趋势观测扩展到对流层顶区域：趋势不确定性和由此产生的辐射强迫。

DOI：
10.1002/jgrd.50831
发表时间：
2013
期刊：
JGR
影响因子：
0
作者：
Kunz A
通讯作者：
Kunz A

Impact of gas-to-particle partitioning approaches on the simulated radiative effects of biogenic secondary organic aerosol

DOI：
10.5194/acp-15-12989-2015
发表时间：
2015-01-01
期刊：
ATMOSPHERIC CHEMISTRY AND PHYSICS
影响因子：
6.3
作者：
Scott, C. E.;Spracklen, D. V.;Pringle, K. J.
通讯作者：
Pringle, K. J.

Impact on short-lived climate forcers increases projected warming due to deforestation.

DOI：
10.1038/s41467-017-02412-4
发表时间：
2018-01-11
期刊：
Nature communications
影响因子：
16.6
作者：
Scott CE;Monks SA;Spracklen DV;Arnold SR;Forster PM;Rap A;Äijälä M;Artaxo P;Carslaw KS;Chipperfield MP;Ehn M;Gilardoni S;Heikkinen L;Kulmala M;Petäjä T;Reddington CLS;Rizzo LV;Swietlicki E;Vignati E;Wilson C
通讯作者：
Wilson C

Small global effect on terrestrial net primary production due to increased fossil fuel aerosol emissions from East Asia since the turn of the century.

DOI：
10.1002/2016gl068965
发表时间：
2016-08-16
期刊：
GEOPHYSICAL RESEARCH LETTERS
影响因子：
5.2
作者：
O'Sullivan, M.;Rap, A.;Reddington, C. L.;Spracklen, D. V.;Gloor, M.;Buermann, W.
通讯作者：
Buermann, W.

Fires increase Amazon forest productivity through increases in diffuse radiation

DOI：
10.1002/2015gl063719
发表时间：
2015-06
期刊：
Geophysical Research Letters
影响因子：
5.2
作者：
A. Rap;D. Spracklen;L. Mercado;C. Reddington;J. Haywood;R. Ellis;O. Phillips;P. Artaxo;D. Bonal;N. R. Coupe;N. Butt
通讯作者：
A. Rap;D. Spracklen;L. Mercado;C. Reddington;J. Haywood;R. Ellis;O. Phillips;P. Artaxo;D. Bonal;N. R. Coupe;N. Butt