气候变化领域集成服务门户(CCPortal): Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model

CCPortal

DOI	10.5194/acp-21-8413-2021
	Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model
	Opacka B.; Müller J.-F.; Stavrakou T.; Bauwens M.; Sindelarova K.; Markova J.; Guenther A.B.
发表日期	2021
ISSN	1680-7316
起始页码	8413
结束页码	8436
卷号	21 期号:11
英文摘要	Among the biogenic volatile organic compounds (BVOCs) emitted by plant foliage, isoprene is by far the most important in terms of both global emission and atmospheric impact. It is highly reactive in the air, and its degradation favours the generation of ozone (in the presence of span classCombining double low line"inline-formula"NOix/i/span) and secondary organic aerosols. A critical aspect of BVOC emission modelling is the representation of land use and land cover (LULC). The current emission inventories are usually based on land cover maps that are either modelled and dynamic or satellite-based and static. In this study, we use the state-of-The-Art Model of Emissions of Gases and Aerosols from Nature (MEGAN) model coupled with the canopy model MOHYCAN (Model for Hydrocarbon emissions by the CANopy) to generate and evaluate emission inventories relying on satellite-based LULC maps at annual time steps. To this purpose, we first intercompare the distribution and evolution (2001-2016) of tree coverage from three global satellite-based datasets, MODerate resolution Imaging Spectroradiometer (MODIS), ESA Climate Change Initiative Land Cover (ESA CCI-LC), and the Global Forest Watch (GFW), and from national inventories. Substantial differences are found between the datasets; e.g.The global areal coverage of trees ranges from 30 to span classCombining double low line"inline-formula"50×106/span span classCombining double low line"inline-formula"km2/span, with trends spanning from span classCombining double low line"inline-formula"-/span0.26 to span classCombining double low line"inline-formula"+/span0.03 span classCombining double low line"inline-formula"% yr-1/span between 2001 and 2016. At the national level, the increasing trends in forest cover reported by some national inventories (in particular for the US) are contradicted by all remotely sensed datasets. To a great extent, these discrepancies stem from the plurality of definitions of forest used. According to some local censuses, clear cut areas and seedling or young trees are classified as forest, while satellite-based mappings of trees rely on a minimum height. Three inventories of isoprene emissions are generated, differing only in their LULC datasets used as input: (i) the static distribution of the stand-Alone version of MEGAN, (ii) the time-dependent MODIS land cover dataset, and (iii) the MODIS dataset modified to match the tree cover distribution from the GFW database. The mean annual isoprene emissions (350-520 span classCombining double low line"inline-formula"Tg yr-1/span) span a wide range due to differences in tree distributions, especially in isoprene-rich regions. The impact of LULC changes is a mitigating effect ranging from 0.04 to 0.33 span classCombining double low line"inline-formula"% yr-1/span on the positive trends (0.94 span classCombining double low line"inline-formula"% yr-1/span) mainly driven by temperature and solar radiation. This study highlights the uncertainty in spatial distributions of and temporal variability in isoprene associated with remotely sensed LULC datasets. The interannual variability in the emissions is evaluated against spaceborne observations of formaldehyde (HCHO), a major isoprene oxidation product, through simulations using the global chemistry transport model (CTM) IMAGESv2. A high correlation (span classCombining double low line"inline-formula"iR/i/span span classCombining double low line"inline-formula">/span 0.8) is found between the observed and simulated interannual variability in HCHO columns in most forested regions. The implementation of LULC change has little impact on this correlation due to the dominance of meteorology as a driver of short-Term interannual variability. Nevertheless, the simulation accounting for the large tree cover declines of the GFW database over several regions, notably Indonesia and Mato Grosso in Brazil, provides the best agreement with the HCHO column trends observed by the Ozonespan idCombining double low line"page8414"/ Monitoring Instrument (OMI). Overall, our study indicates that the continuous tree cover fields at fine resolution provided by the GFW database are our preferred choice for constraining LULC (in combination with discrete LULC maps such as those of MODIS) in biogenic isoprene emission models./ © 2021 Copernicus GmbH. All rights reserved.
语种	英语
scopus关键词	aerosol; emission; emission inventory; forest cover; isoprene; land cover; land use change; MODIS; volatile organic compound
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246840
作者单位	Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Avenue Circulaire 3, Brussels, 1180, Belgium; Department of Atmospheric Physics, Charles University in Prague, Prague, Czech Republic; Czech Hydrometeorological Institute (CHMI), Na Šabatce 17, Prague 4, 14306, Czech Republic; Department of Earth System Science, University of California Irvine, California, 92697, United States
推荐引用方式 GB/T 7714	Opacka B.,Müller J.-F.,Stavrakou T.,et al. Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model[J],2021,21(11).
APA	Opacka B..,Müller J.-F..,Stavrakou T..,Bauwens M..,Sindelarova K..,...&Guenther A.B..(2021).Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(11).
MLA	Opacka B.,et al."Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.11(2021).