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  1. Article ; Online: Biomass burning combustion efficiency observed from space using measurements of CO and NO 2 by the TROPOspheric Monitoring Instrument (TROPOMI)

    I. R. van der Velde / G. R. van der Werf / S. Houweling / H. J. Eskes / J. P. Veefkind / T. Borsdorff / I. Aben

    Atmospheric Chemistry and Physics, Vol 21, Pp 597-

    2021  Volume 616

    Abstract: The global fire emission inventories depend on ground and airborne measurements of species-specific emission factors (EFs), which translate dry matter losses due to fires to actual trace gas and aerosol emissions. The EFs of nitrogen oxides (NO x ) and ... ...

    Abstract The global fire emission inventories depend on ground and airborne measurements of species-specific emission factors (EFs), which translate dry matter losses due to fires to actual trace gas and aerosol emissions. The EFs of nitrogen oxides (NO x ) and carbon monoxide (CO) can function as a proxy for combustion efficiency to distinguish flaming from smoldering combustion. The uncertainties in these EFs remain large as they are limited by the spatial and temporal representativeness of the measurements. The global coverage of satellite observations has the advantage of filling this gap, making these measurements highly complementary to ground-based or airborne data. We present a new analysis of biomass burning pollutants using space-borne data to investigate the spatiotemporal efficiency of fire combustion. Column measurements of nitrogen dioxide and carbon monoxide ( X NO 2 and X CO ) from the TROPOspheric Monitoring Instrument (TROPOMI) are used to quantify the relative atmospheric enhancements of these species over different fire-prone regions around the world. We find spatial and temporal patterns in the Δ X NO 2 ∕ Δ X CO ratio that point to distinct differences in biomass burning behavior. Such differences are induced by the burning phase of the fire (e.g., high-temperature flaming vs. low-temperature smoldering combustion) and burning practice (e.g., the combustion of logs, coarse woody debris and soil organic matter vs. the combustion of fine fuels such as savanna grasses). The sampling techniques and the signal-to-noise ratio of the retrieved Δ X NO 2 ∕ Δ X CO signals were quantified with WRF-Chem experiments and showed similar distinct differences in combustion types. The TROPOMI measurements show that the fraction of surface smoldering combustion is much larger for the boreal forest fires in the upper Northern Hemisphere and peatland fires in Indonesia. These types of fires cause a much larger increase (3 to 6 times) in Δ X CO relative to Δ X NO 2 than elsewhere in the world. The high spatial and ...
    Keywords Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 550
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Towards multi-tracer data-assimilation

    I. R. van der Velde / J. B. Miller / K. Schaefer / G. R. van der Werf / M. C. Krol / W. Peters

    Biogeosciences Discussions, Vol 11, Iss 1, Pp 107-

    biomass burning and carbon isotope exchange in SiBCASA

    2014  Volume 149

    Abstract: We present an enhanced version of the SiBCASA photosynthetic/biogeochemical model for a future integration with a multi-tracer data-assimilation system. We extended the model with (a) biomass burning emissions from the SiBCASA carbon pools using remotely ...

    Abstract We present an enhanced version of the SiBCASA photosynthetic/biogeochemical model for a future integration with a multi-tracer data-assimilation system. We extended the model with (a) biomass burning emissions from the SiBCASA carbon pools using remotely sensed burned area from Global Fire Emissions Database (GFED) version 3.1, (b) a new set of 13 C pools that cycle consistently through the biosphere, and (c), a modified isotopic discrimination scheme to estimate variations in 13 C exchange as a~response to stomatal conductance. Previous studies suggest that the observed variations of atmospheric 13 C/ 12 C are driven by processes specifically in the terrestrial biosphere rather than in the oceans. Therefore, we quantify in this study the terrestrial exchange of CO 2 and 13 CO 2 as a function of environmental changes in humidity and biomass burning. Based on an assessment of observed respiration signatures we conclude that SiBCASA does well in simulating global to regional plant discrimination. The global mean discrimination value is 15.2‰, and ranges between 4 and 20‰ depending on the regional plant phenology. The biomass burning emissions (annually and seasonally) compare favorably to other published values. However, the observed short-term changes in discrimination and the respiration 13 C signature are more difficult to capture. We see a too weak drought response in SiBCASA and too slow return of anomalies in respiration. We demonstrate possible ways to improve this, and discuss the implications for our current capacity to interpret atmospheric 13 C observations.
    Keywords Geology ; QE1-996.5 ; Science ; Q ; DOAJ:Earth Sciences ; DOAJ:Earth and Environmental Sciences ; Biology (General) ; QH301-705.5 ; DOAJ:Biology ; DOAJ:Biology and Life Sciences ; Evolution ; QH359-425 ; Ecology ; QH540-549.5 ; Life ; QH501-531
    Subject code 333
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Terrestrial cycling of 13 CO 2 by photosynthesis, respiration, and biomass burning in SiBCASA

    I. R. van der Velde / J. B. Miller / K. Schaefer / G. R. van der Werf / M. C. Krol / W. Peters

    Biogeosciences, Vol 11, Iss 23, Pp 6553-

    2014  Volume 6571

    Abstract: We present an enhanced version of the SiBCASA terrestrial biosphere model that is extended with (a) biomass burning emissions from the SiBCASA carbon pools using remotely sensed burned area from the Global Fire Emissions Database (GFED), (b) an isotopic ... ...

    Abstract We present an enhanced version of the SiBCASA terrestrial biosphere model that is extended with (a) biomass burning emissions from the SiBCASA carbon pools using remotely sensed burned area from the Global Fire Emissions Database (GFED), (b) an isotopic discrimination scheme that calculates 13 C signatures of photosynthesis and autotrophic respiration, and (c) a separate set of 13 C pools to carry isotope ratios into heterotrophic respiration. We quantify in this study the terrestrial exchange of CO 2 and 13 CO 2 as a function of environmental changes in humidity and biomass burning. The implementation of biomass burning yields similar fluxes as CASA-GFED both in magnitude and spatial patterns. The implementation of isotope exchange gives a global mean discrimination value of 15.2‰, ranges between 4 and 20‰ depending on the photosynthetic pathway in the plant, and compares favorably (annually and seasonally) with other published values. Similarly, the isotopic disequilibrium is similar to other studies that include a small effect of biomass burning as it shortens the turnover of carbon. In comparison to measurements, a newly modified starch/sugar storage pool propagates the isotopic discrimination anomalies to respiration much better. In addition, the amplitude of the drought response by SiBCASA is lower than suggested by the measured isotope ratios. We show that a slight increase in the stomatal closure for large vapor pressure deficit would amplify the respired isotope ratio variability. Our study highlights the importance of isotope ratio observations of 13 C to assess and improve biochemical models like SiBCASA, especially with regard to the allocation and turnover of carbon and the responses to drought.
    Keywords Ecology ; QH540-549.5 ; Life ; QH501-531 ; Geology ; QE1-996.5
    Subject code 333
    Language English
    Publishing date 2014-12-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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    Inter-library loan at ZB MED

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  4. Article ; Online: The effect of assimilating satellite-derived soil moisture data in SiBCASA on simulated carbon fluxes in Boreal Eurasia

    M. K. van der Molen / R. A. M. de Jeu / W. Wagner / I. R. van der Velde / P. Kolari / J. Kurbatova / A. Varlagin / T. C. Maximov / A. V. Kononov / T. Ohta / A. Kotani / M. C. Krol / W. Peters

    Hydrology and Earth System Sciences, Vol 20, Iss 2, Pp 605-

    2016  Volume 624

    Abstract: Boreal Eurasia is a region where the interaction between droughts and the carbon cycle may have significant impacts on the global carbon cycle. Yet the region is extremely data sparse with respect to meteorology, soil moisture, and carbon fluxes as ... ...

    Abstract Boreal Eurasia is a region where the interaction between droughts and the carbon cycle may have significant impacts on the global carbon cycle. Yet the region is extremely data sparse with respect to meteorology, soil moisture, and carbon fluxes as compared to e.g. Europe. To better constrain our vegetation model SiBCASA, we increase data usage by assimilating two streams of satellite-derived soil moisture. We study whether the assimilation improved SiBCASA's soil moisture and its effect on the simulated carbon fluxes. By comparing to unique in situ soil moisture observations, we show that the passive microwave soil moisture product did not improve the soil moisture simulated by SiBCASA, but the active data seem promising in some aspects. The match between SiBCASA and ASCAT soil moisture is best in the summer months over low vegetation. Nevertheless, ASCAT failed to detect the major droughts occurring between 2007 and 2013. The performance of ASCAT soil moisture seems to be particularly sensitive to ponding, rather than to biomass. The effect on the simulated carbon fluxes is large, 5–10 % on annual GPP and TER, tens of percent on local NEE, and 2 % on area-integrated NEE, which is the same order of magnitude as the inter-annual variations. Consequently, this study shows that assimilation of satellite-derived soil moisture has potentially large impacts, while at the same time further research is needed to understand under which conditions the satellite-derived soil moisture improves the simulated soil moisture.
    Keywords Technology ; T ; Environmental technology. Sanitary engineering ; TD1-1066 ; Geography. Anthropology. Recreation ; G ; Environmental sciences ; GE1-350
    Subject code 550
    Language English
    Publishing date 2016-02-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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    Inter-library loan at ZB MED

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  5. Article ; Online: Simulating the integrated summertime Δ 14 CO 2 signature from anthropogenic emissions over Western Europe

    D. Bozhinova / M. K. van der Molen / I. R. van der Velde / M. C. Krol / S. van der Laan / H. A. J. Meijer / W. Peters

    Atmospheric Chemistry and Physics, Vol 14, Iss 14, Pp 7273-

    2014  Volume 7290

    Abstract: Radiocarbon dioxide ( 14 CO 2 , reported in Δ 14 CO 2 ) can be used to determine the fossil fuel CO 2 addition to the atmosphere, since fossil fuel CO 2 no longer contains any 14 C. After the release of CO 2 at the source, atmospheric transport causes ... ...

    Abstract Radiocarbon dioxide ( 14 CO 2 , reported in Δ 14 CO 2 ) can be used to determine the fossil fuel CO 2 addition to the atmosphere, since fossil fuel CO 2 no longer contains any 14 C. After the release of CO 2 at the source, atmospheric transport causes dilution of strong local signals into the background and detectable gradients of Δ 14 CO 2 only remain in areas with high fossil fuel emissions. This fossil fuel signal can moreover be partially masked by the enriching effect that anthropogenic emissions of 14 CO 2 from the nuclear industry have on the atmospheric Δ 14 CO 2 signature. In this paper, we investigate the regional gradients in 14 CO 2 over the European continent and quantify the effect of the emissions from nuclear industry. We simulate the emissions and transport of fossil fuel CO 2 and nuclear 14 CO 2 for Western Europe using the Weather Research and Forecast model (WRF-Chem) for a period covering 6 summer months in 2008. We evaluate the expected CO 2 gradients and the resulting Δ 14 CO 2 in simulated integrated air samples over this period, as well as in simulated plant samples. We find that the average gradients of fossil fuel CO 2 in the lower 1200 m of the atmosphere are close to 15 ppm at a 12 km × 12 km horizontal resolution. The nuclear influence on Δ 14 CO 2 signatures varies considerably over the domain and for large areas in France and the UK it can range from 20 to more than 500% of the influence of fossil fuel emissions. Our simulations suggest that the resulting gradients in Δ 14 CO 2 are well captured in plant samples, but due to their time-varying uptake of CO 2 , their signature can be different with over 3‰ from the atmospheric samples in some regions. We conclude that the framework presented will be well-suited for the interpretation of actual air and plant 14 CO 2 samples.
    Keywords Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 333 ; 290
    Language English
    Publishing date 2014-07-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

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    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article ; Online: The effect of assimilating satellite derived soil moisture in SiBCASA on simulated carbon fluxes in Boreal Eurasia

    M. K. van der Molen / R. A. M. de Jeu / W. Wagner / I. R. van der Velde / P. Kolari / J. Kurbatova / A. Varlagin / T. C. Maximov / A. V. Kononov / T. Ohta / A. Kotani / M. C. Krol / W. Peters

    Hydrology and Earth System Sciences Discussions, Vol 12, Iss 9, Pp 9003-

    2015  Volume 9054

    Abstract: Boreal Eurasia is a region where the interaction between droughts and the carbon cycle may have significant impacts on the global carbon cycle. Yet the region is extremely data sparse with respect to meteorology, soil moisture and carbon fluxes as ... ...

    Abstract Boreal Eurasia is a region where the interaction between droughts and the carbon cycle may have significant impacts on the global carbon cycle. Yet the region is extremely data sparse with respect to meteorology, soil moisture and carbon fluxes as compared to e.g. Europe. To better constrain our vegetation model SiBCASA, we increase data usage by assimilating two streams of satellite derived soil moisture. We study if the assimilation improved SiBCASA's soil moisture and its effect on the simulated carbon fluxes. By comparing to unique in situ soil moisture observations, we show that the passive microwave soil moisture product did not improve the soil moisture simulated by SiBCASA, but the active data seem promising in some aspects. The match between SiBCASA and ASCAT soil moisture is best in the summer months over low vegetation. Nevertheless, ASCAT failed to detect the major droughts occurring between 2007 and 2013. The performance of ASCAT soil moisture seems to be particularly sensitive to ponding, rather than to biomass. The effect on the simulated carbon fluxes is large, 5–10% on annual GPP and TER, and tens of percent on local NEE, and 2% on area-integrated NEE, which is the same order of magnitude as the inter-annual variations. Consequently, this study shows that assimilation of satellite derived soil moisture has potentially large impacts, while at the same time further research is needed to understand under which conditions the satellite derived soil moisture improves the simulated soil moisture.
    Keywords Physical geography ; GB3-5030
    Subject code 550
    Language English
    Publishing date 2015-09-01T00:00:00Z
    Publisher Copernicus Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

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    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

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