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Article ; Online: Satellite evidence for changes in the NO2 weekly cycle over large cities

T. Stavrakou / J.-F. Müller / M. Bauwens / K. F. Boersma / J. van Geffen

Scientific Reports, Vol 10, Iss 1, Pp 1-

2020 Volume 9

Abstract: Abstract Anthropogenic activities, by far the largest source of NOx into the atmosphere, induce a weekly cycle of NO2 abundances in cities. Comprehensive analysis of the 2005–2017 OMI NO2 dataset reveals significant weekly cycles in 115 of the 274 cities ...

Abstract	Abstract Anthropogenic activities, by far the largest source of NOx into the atmosphere, induce a weekly cycle of NO2 abundances in cities. Comprehensive analysis of the 2005–2017 OMI NO2 dataset reveals significant weekly cycles in 115 of the 274 cities considered. These results are corroborated by a full year of high-resolution TROPOMI NO2 observations. The OMI dataset permits us to identify trends in the weekly cycle resulting from NOx emissions changes. The data show a clear weakening of the weekly cycle over European and U.S. cities, an evolution attributed to the decline in anthropogenic emissions and the resulting growing importance of background NO2, whereas NO2 lifetime changes also play a minor role. In particular, the Sunday NO2 columns averaged over all U.S. cities are found to increase, relative to the weekly average, from 0.72 during 2005–2007 to 0.88 in 2015–2017. The opposite tendency is recorded in regions undergoing rapid emission growth. Multiyear simulations over the U.S. and the Middle East using the chemistry-transport model MAGRITTEv1.1 succeed in capturing the observed weekly cycles over the largest cities, as well as the observed long-term trends in the weekly cycle.
Keywords	Medicine ; R ; Science ; Q
Subject code	551
Language	English
Publishing date	2020-06-01T00:00:00Z
Publisher	Nature Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Global and regional impacts of land cover changes on isoprene emissions derived from spaceborne data and the MEGAN model

B. Opacka / J.-F. Müller / T. Stavrakou / M. Bauwens / K. Sindelarova / J. Markova / A. B. Guenther

Atmospheric Chemistry and Physics, Vol 21, Pp 8413-

2021 Volume 8436

Abstract: 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 ...

Abstract	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 NO x ) 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 50×10 6 km 2 , with trends spanning from − 0.26 to + 0.03 % yr −1 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, ...
Keywords	Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	333
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Air quality impacts of COVID-19 lockdown measures detected from space using high spatial resolution observations of multiple trace gases from Sentinel-5P/TROPOMI

P. F. Levelt / D. C. Stein Zweers / I. Aben / M. Bauwens / T. Borsdorff / I. De Smedt / H. J. Eskes / C. Lerot / D. G. Loyola / F. Romahn / T. Stavrakou / N. Theys / M. Van Roozendael / J. P. Veefkind / T. Verhoelst

Atmospheric Chemistry and Physics, Vol 22, Pp 10319-

2022 Volume 10351

Abstract: The aim of this paper is to highlight how TROPOspheric Monitoring Instrument (TROPOMI) trace gas data can best be used and interpreted to understand event-based impacts on air quality from regional to city scales around the globe. For this study, we ... ...

Abstract	The aim of this paper is to highlight how TROPOspheric Monitoring Instrument (TROPOMI) trace gas data can best be used and interpreted to understand event-based impacts on air quality from regional to city scales around the globe. For this study, we present the observed changes in the atmospheric column amounts of five trace gases (NO 2 , SO 2 , CO, HCHO, and CHOCHO) detected by the Sentinel-5P TROPOMI instrument and driven by reductions in anthropogenic emissions due to COVID-19 lockdown measures in 2020. We report clear COVID-19-related decreases in TROPOMI NO 2 column amounts on all continents. For megacities, reductions in column amounts of tropospheric NO 2 range between 14 % and 63 %. For China and India, supported by NO 2 observations, where the primary source of anthropogenic SO 2 is coal-fired power generation, we were able to detect sector-specific emission changes using the SO 2 data. For HCHO and CHOCHO, we consistently observe anthropogenic changes in 2-week-averaged column amounts over China and India during the early phases of the lockdown periods. That these variations over such a short timescale are detectable from space is due to the high resolution and improved sensitivity of the TROPOMI instrument. For CO, we observe a small reduction over China, which is in concert with the other trace gas reductions observed during lockdown; however, large interannual differences prevent firm conclusions from being drawn. The joint analysis of COVID-19-lockdown-driven reductions in satellite-observed trace gas column amounts using the latest operational and scientific retrieval techniques for five species concomitantly is unprecedented. However, the meteorologically and seasonally driven variability of the five trace gases does not allow for drawing fully quantitative conclusions on the reduction in anthropogenic emissions based on TROPOMI observations alone. We anticipate that in future the combined use of inverse modeling techniques with the high spatial resolution data from S5P/TROPOMI for all observed ...
Keywords	Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	550 ; 520
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Isoprene emissions over Asia 1979–2012

T. Stavrakou / J.-F. Müller / M. Bauwens / I. De Smedt / M. Van Roozendael / A. Guenther / M. Wild / X. Xia

Atmospheric Chemistry and Physics, Vol 14, Iss 9, Pp 4587-

impact of climate and land-use changes

2014 Volume 4605

Abstract: Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing ...

Abstract	Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing bottom-up estimates, and to investigate the temporal evolution of the fluxes in Asia over 1979–2012. To this purpose, we calculate the hourly emissions at 0.5°×0.5° resolution using the MEGAN–MOHYCAN model driven by ECMWF ERA-Interim climatology. In order to remedy for known biases identified in previous studies, and to improve the simulation of interannual variability and trends in emissions, this study incorporates (i) changes in land use, including the rapid expansion of oil palms, (ii) meteorological variability according to ERA-Interim, (iii) long-term changes in solar radiation (dimming/brightening) constrained by surface network radiation measurements, and (iv) recent experimental evidence that South Asian tropical forests are much weaker isoprene emitters than previously assumed, and on the other hand, that oil palms have a strong isoprene emission capacity. These effects lead to a significant lowering (factor of 2) in the total isoprene fluxes over the studied domain, and to emission reductions reaching a factor of 3.5 in Southeast Asia. The bottom-up annual isoprene emissions for 2005 are estimated at 7.0, 4.8, 8.3, and 2.9 Tg in China, India, Indonesia and Malaysia, respectively. The isoprene flux anomaly over the whole domain and studied period is found to be strongly correlated with the Oceanic Niño Index ( r = 0.73), with positive (negative) anomalies related to El Niño (La Niña) years. Changes in temperature and solar radiation are the major drivers of the interannual variability and trends in the emissions, except over semi-arid areas such as northwestern China, Pakistan and Kazakhstan, where soil moisture is by far the main cause of interannual emission changes. In our base simulation, annual positive flux trends of 0.2% and 0.52% throughout the ...
Keywords	Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	950
Language	English
Publishing date	2014-05-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Intercomparison of Magnitudes and Trends in Anthropogenic Surface Emissions From Bottom‐Up Inventories, Top‐Down Estimates, and Emission Scenarios

N. Elguindi / C. Granier / T. Stavrakou / S. Darras / M. Bauwens / H. Cao / C. Chen / H. A. C. Denier van der Gon / O. Dubovik / T. M. Fu / D. K. Henze / Z. Jiang / S. Keita / J. J. P. Kuenen / J. Kurokawa / C. Liousse / K. Miyazaki / J.‐F. Müller / Z. Qu /

F. Solmon / B. Zheng

Earth's Future, Vol 8, Iss 8, Pp n/a-n/a (2020)

2020

Abstract: Abstract This study compares recent CO, NOx, NMVOC, SO2, BC, and OC anthropogenic emissions from several state‐of‐the‐art top‐down estimates to global and regional bottom‐up inventories and projections from five Shared Socioeconomic Pathways (SSPs) in ... ...

Abstract	Abstract This study compares recent CO, NOx, NMVOC, SO2, BC, and OC anthropogenic emissions from several state‐of‐the‐art top‐down estimates to global and regional bottom‐up inventories and projections from five Shared Socioeconomic Pathways (SSPs) in several regions. Results show that top‐down emissions derived in several recent studies exhibit similar uncertainty as bottom‐up inventories in some regions for certain species and even less in the case of Chinese CO emissions. In general, the largest discrepancies are found outside of regions such as the United States, Europe, and Japan where the most accurate and detailed information on emissions is available. In some regions such as China, which has recently undergone dynamical economic growth and changes in air quality regulations, the top‐down estimates better capture recent emission trends than global bottom‐up inventories. These results show the potential of top‐down estimates to complement bottom‐up inventories and to aide in the development of emission scenarios, particularly in regions where global inventories lack the necessary up‐to‐date and accurate information regarding regional activity data and emission factors such as Africa and India. Areas of future work aimed at quantifying and reducing uncertainty are also highlighted. A regional comparison of recent CO and NOx trends in the five SSPs indicate that SSP126, a strong pollution control scenario, best represents the trends from the top‐down and regional bottom‐up inventories in the United States, Europe, and China, while SSP460, a low‐pollution control scenario, lies closest to actual trends in West Africa. This analysis can be useful for air quality forecasting and near‐future pollution control/mitigation policy studies.
Keywords	Anthropogenic surface emissions ; Inverse Modelling ; Shared Socioeconomic Pathways ; Air quality modelling ; Emission inventories ; Environmental sciences ; GE1-350 ; Ecology ; QH540-549.5
Subject code	910
Language	English
Publishing date	2020-08-01T00:00:00Z
Publisher	Wiley
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Recent past (1979–2014) and future (2070–2099) isoprene fluxes over Europe simulated with the MEGAN–MOHYCAN model

M. Bauwens / T. Stavrakou / J.-F. Müller / B. Van Schaeybroeck / L. De Cruz / R. De Troch / O. Giot / R. Hamdi / P. Termonia / Q. Laffineur / C. Amelynck / N. Schoon / B. Heinesch / T. Holst / A. Arneth / R. Ceulemans / A. Sanchez-Lorenzo / A. Guenther

Biogeosciences, Vol 15, Pp 3673-

2018 Volume 3690

Abstract: Isoprene is a highly reactive volatile organic compound emitted by vegetation, known to be a precursor of secondary organic aerosols and to enhance tropospheric ozone formation under polluted conditions. Isoprene emissions respond strongly to changes in ... ...

Abstract	Isoprene is a highly reactive volatile organic compound emitted by vegetation, known to be a precursor of secondary organic aerosols and to enhance tropospheric ozone formation under polluted conditions. Isoprene emissions respond strongly to changes in meteorological parameters such as temperature and solar radiation. In addition, the increasing CO 2 concentration has a dual effect, as it causes both a direct emission inhibition as well as an increase in biomass through fertilization. In this study we used the MEGAN (Model of Emissions of Gases and Aerosols from Nature) emission model coupled with the MOHYCAN (Model of HYdrocarbon emissions by the CANopy) canopy model to calculate the isoprene fluxes emitted by vegetation in the recent past (1979–2014) and in the future (2070–2099) over Europe at a resolution of 0.1° × 0.1°. As a result of the changing climate, modeled isoprene fluxes increased by 1.1 % yr −1 on average in Europe over 1979–2014, with the strongest trends found over eastern Europe and European Russia, whereas accounting for the CO 2 inhibition effect led to reduced emission trends (0.76 % yr −1 ). Comparisons with field campaign measurements at seven European sites suggest that the MEGAN–MOHYCAN model provides a reliable representation of the temporal variability of the isoprene fluxes over timescales between 1 h and several months. For the 1979–2014 period the model was driven by the ECMWF ERA-Interim reanalysis fields, whereas for the comparison of current with projected future emissions, we used meteorology simulated with the ALARO regional climate model. Depending on the representative concentration pathway (RCP) scenarios for greenhouse gas concentration trajectories driving the climate projections, isoprene emissions were found to increase by +7 % (RCP2.6), +33 % (RCP4.5), and +83 % (RCP8.5), compared to the control simulation, and even stronger increases were found when considering the potential impact of CO 2 fertilization: +15 % (RCP2.6), +52 % (RCP4.5), and +141 % (RCP8.5). However, ...
Keywords	Ecology ; QH540-549.5 ; Life ; QH501-531 ; Geology ; QE1-996.5
Subject code	550
Language	English
Publishing date	2018-06-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: A nonlinear multi-proxy model based on manifold learning to reconstruct water temperature from high resolution trace element profiles in biogenic carbonates

M. Bauwens / H. Ohlsson / K. Barbé / V. Beelaerts / J. Schoukens / F. Dehairs

Geoscientific Model Development, Vol 3, Iss 2, Pp 653-

2010 Volume 667

Abstract: A long standing problem in paleoceanography concerns the reconstruction of water temperature from δ 18 O carbonate. It is problematic in the case of freshwater influenced environments because the δ 18 O isotopic composition of the ambient water (related ... ...

Abstract	A long standing problem in paleoceanography concerns the reconstruction of water temperature from δ 18 O carbonate. It is problematic in the case of freshwater influenced environments because the δ 18 O isotopic composition of the ambient water (related to salinity) needs to be known. In this paper we argue for the use of a nonlinear multi-proxy method called Weight Determination by Manifold Regularization (WDMR) to develop a temperature reconstruction model that is less sensitive to salinity variations. The motivation for using this type of model is twofold: firstly, observed nonlinear relations between specific proxies and water temperature motivate the use of nonlinear models. Secondly, the use of multi-proxy models enables salinity related variations of a given temperature proxy to be explained by salinity-related information carried by a separate proxy. Our findings confirm that Mg/Ca is a powerful paleothermometer and highlight that reconstruction performance based on this proxy is improved significantly by combining its information with the information for other trace elements in multi-proxy models. Although the models presented here are black-box models that do not use any prior knowledge about the proxies, the comparison of model reconstruction performances based on different proxy combinations do yield useful information about proxy characteristics. Using Mg/Ca, Sr/Ca, Ba/Ca and Pb/Ca the WDMR model enables a temperature reconstruction with a root mean squared error of ± 2.19 °C for a salinity range between 15 and 32.
Keywords	Geology ; QE1-996.5 ; Science ; Q ; DOAJ:Earth Sciences ; DOAJ:Earth and Environmental Sciences
Subject code	551
Language	English
Publishing date	2010-11-01T00:00:00Z
Publisher	Copernicus Publications
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Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: A nonlinear multi-proxy model based on manifold learning to reconstruct water temperature from high resolution trace element profiles in biogenic carbonates

M. Bauwens / H. Ohlsson / K. Barbé / V. Beelaerts / F. Dehairs / J. Schoukens

Geoscientific Model Development Discussions, Vol 3, Iss 3, Pp 1105-

2010 Volume 1138

Abstract: A long standing problem in paleoceanography concerns the reconstruction of water temperature from δ 18 O carbonate, which for freshwater influenced environments is hindered because the isotopic composition of the ambient water (related to salinity) ... ...

Abstract	A long standing problem in paleoceanography concerns the reconstruction of water temperature from δ 18 O carbonate, which for freshwater influenced environments is hindered because the isotopic composition of the ambient water (related to salinity) affects the reconstructed temperature. In this paper we argue for the use of a nonlinear multi-proxy method called Weight Determination by Manifold Regularization to develop a temperature reconstruction model that is less sensitive to salinity variations. The motivation for using this type of model is twofold: Firstly, observed nonlinear relations between specific proxies and water temperature motivate the use of nonlinear models. Secondly, the use of multi-proxy models enables salinity related variations of a given temperature proxy to be explained by salinity-related information carried by a separate proxy. Our findings confirm that Mg/Ca is a powerful paleothermometer and highlight that reconstruction performance based on this proxy is improved significantly by combining its information with the information of other trace elements in multi-proxy models. Using Mg/Ca, Sr/Ca, Ba/Ca and Pb/Ca the WDMR model enabled a temperature reconstruction with a root mean squared error of ±2.19 °C for a salinity range between 15 and 32.
Keywords	Geology ; QE1-996.5 ; Science ; Q ; DOAJ:Earth Sciences ; DOAJ:Earth and Environmental Sciences ; Geography (General) ; G1-922
Subject code	551
Language	English
Publishing date	2010-07-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Nine years of global hydrocarbon emissions based on source inversion of OMI formaldehyde observations

M. Bauwens / T. Stavrakou / J.-F. Müller / I. De Smedt / M. Van Roozendael / G. R. van der Werf / C. Wiedinmyer / J. W. Kaiser / K. Sindelarova / A. Guenther

Atmospheric Chemistry and Physics, Vol 16, Pp 10133-

2016 Volume 10158

Abstract: As formaldehyde (HCHO) is a high-yield product in the oxidation of most volatile organic compounds (VOCs) emitted by fires, vegetation, and anthropogenic activities, satellite observations of HCHO are well-suited to inform us on the spatial and temporal ... ...

Abstract	As formaldehyde (HCHO) is a high-yield product in the oxidation of most volatile organic compounds (VOCs) emitted by fires, vegetation, and anthropogenic activities, satellite observations of HCHO are well-suited to inform us on the spatial and temporal variability of the underlying VOC sources. The long record of space-based HCHO column observations from the Ozone Monitoring Instrument (OMI) is used to infer emission flux estimates from pyrogenic and biogenic volatile organic compounds (VOCs) on the global scale over 2005–2013. This is realized through the method of source inverse modeling, which consists in the optimization of emissions in a chemistry-transport model (CTM) in order to minimize the discrepancy between the observed and modeled HCHO columns. The top–down fluxes are derived in the global CTM IMAGESv2 by an iterative minimization algorithm based on the full adjoint of IMAGESv2, starting from a priori emission estimates provided by the newly released GFED4s (Global Fire Emission Database, version 4s) inventory for fires, and by the MEGAN-MOHYCAN inventory for isoprene emissions. The top–down fluxes are compared to two independent inventories for fire (GFAS and FINNv1.5) and isoprene emissions (MEGAN-MACC and GUESS-ES). The inversion indicates a moderate decrease (ca. 20 %) in the average annual global fire and isoprene emissions, from 2028 Tg C in the a priori to 1653 Tg C for burned biomass, and from 343 to 272 Tg for isoprene fluxes. Those estimates are acknowledged to depend on the accuracy of formaldehyde data, as well as on the assumed fire emission factors and the oxidation mechanisms leading to HCHO production. Strongly decreased top–down fire fluxes (30–50 %) are inferred in the peak fire season in Africa and during years with strong a priori fluxes associated with forest fires in Amazonia (in 2005, 2007, and 2010), bushfires in Australia (in 2006 and 2011), and peat burning in Indonesia (in 2006 and 2009), whereas generally increased fluxes are suggested in Indochina and during the 2007 ...
Keywords	Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	333
Language	English
Publishing date	2016-08-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

T. Stavrakou / J.-F. Müller / M. Bauwens / I. De Smedt / M. Van Roozendael / M. De Mazière / C. Vigouroux / F. Hendrick / M. George / C. Clerbaux / P.-F. Coheur / A. Guenther

Atmospheric Chemistry and Physics, Vol 15, Iss 20, Pp 11861-

2015 Volume 11884

Abstract: The vertical columns of formaldehyde (HCHO) retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2) on Metop-A and the Ozone Monitoring Instrument (OMI) on Aura, are used to constrain global emissions of HCHO ... ...

Abstract	The vertical columns of formaldehyde (HCHO) retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2) on Metop-A and the Ozone Monitoring Instrument (OMI) on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the adjoint model technique in the IMAGESv2 global CTM (chemical transport model) on a monthly basis and at the model resolution. Given the different local overpass times of GOME-2 (09:30 LT) and OMI (13:30 LT), the simulated diurnal cycle of HCHO columns is investigated and evaluated against ground-based optical measurements at seven sites in Europe, China and Africa. The modeled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon maxima at remote locations (oceans) and in regions dominated by anthropogenic emissions, late afternoon or evening maxima over fire scenes, and midday minima in isoprene-rich regions. The agreement between simulated and ground-based columns is generally better in summer (with a clear afternoon maximum at mid-latitude sites) than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126) than in the ground-based measurements (1.043). The anthropogenic VOC (volatile organic compound) sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly polluted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inventory (24.6 vs. 25.5 TgVOC yr −1 in the a priori) with, however, pronounced increases in the northeast of China and reductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC yr −1 ), in particular over the northeast, likely reflecting mismatches between the observed ...
Keywords	Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	551
Language	English
Publishing date	2015-10-01T00:00:00Z
Publisher	Copernicus Publications
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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