Showing papers by "Martin Heimann published in 2020"
European Commission1, European Centre for Medium-Range Weather Forecasts2, European Space Research and Technology Centre3, University of Leicester4, EUMETSAT5, Swiss Federal Laboratories for Materials Science and Technology6, University of Bremen7, California Institute of Technology8, Netherlands Organisation for Applied Scientific Research9, VU University Amsterdam10, Lille University of Science and Technology11, Japan Aerospace Exploration Agency12, University of Edinburgh13, University of Melbourne14, Finnish Meteorological Institute15, Royal Netherlands Meteorological Institute16
TL;DR: In this paper, the authors present an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under the EC's Copernicus program, which adopts a holistic view and includes components such as atmospheric spaceborne and in situ measurements, bottom-up CO2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottomup information, and a policy-relevant decision support tool.
Abstract: Under the Paris Agreement (PA), progress of emission reduction efforts is tracked on the basis of regular updates to national greenhouse gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today, there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories. The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites, and international experts are joining forces to develop such an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under the EC's Copernicus program. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO2 emissions Monitoring and Verification Support (CO2MVS) capacity. It adopts a holistic view and includes components such as atmospheric spaceborne and in situ measurements, bottom-up CO2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool. The CO2MVS capacity with operational capabilities by 2026 is expected to visualize regular updates of global CO2 emissions, likely at 0.05° x 0.05°. This will complement the PA's enhanced transparency framework, providing actionable information on anthropogenic CO2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave the green light to pass the CO2MVS from exploratory to implementing phase.
60 citations
TL;DR: Variations in the regional net ecosystem exchange of CO2 between terrestrial ecosystems and the atmosphere were quantified from measurements of atmospheric CO2 mole fractions to indicate the year-to-year variations of Europe’s carbon sources and sinks, at least in summer.
Abstract: In 2018, central and northern parts of Europe experienced heat and drought conditions over many months from spring to autumn, strongly affecting both natural ecosystems and crops. Besides their imp...
20 citations
Peking University1, Centre national de la recherche scientifique2, Chinese Academy of Sciences3, University of California, San Diego4, Max Planck Society5, University of Helsinki6, University of Exeter7, University of California, Los Angeles8, Augsburg College9, University of Victoria10, Commonwealth Scientific and Industrial Research Organisation11, University of Illinois at Urbana–Champaign12, Oeschger Centre for Climate Change Research13, National Center for Atmospheric Research14, Goddard Space Flight Center15, Met Office16, University of Maryland, College Park17
TL;DR: The result challenges the view that CO2 fertilization is the dominant cause of emergent SCA trends at northern sites south of 40°N and shows the necessity to adequately account for changing circulation patterns in understanding carbon cycle dynamics observed from atmospheric observations and in using these observations to benchmark DGVMs.
Abstract: Changing amplitude of the seasonal cycle of atmospheric CO2 (SCA) in the northern hemisphere is an emerging carbon cycle property. Mauna Loa (MLO) station (20°N, 156°W), which has the longest continuous northern hemisphere CO2 record, shows an increasing SCA before the 1980s (p < .01), followed by no significant change thereafter. We analyzed the potential driving factors of SCA slowing-down, with an ensemble of dynamic global vegetation models (DGVMs) coupled with an atmospheric transport model. We found that slowing-down of SCA at MLO is primarily explained by response of net biome productivity (NBP) to climate change, and by changes in atmospheric circulations. Through NBP, climate change increases SCA at MLO before the 1980s and decreases it afterwards. The effect of climate change on the slowing-down of SCA at MLO is mainly exerted by intensified drought stress acting to offset the acceleration driven by CO2 fertilization. This challenges the view that CO2 fertilization is the dominant cause of emergent SCA trends at northern sites south of 40°N. The contribution of agricultural intensification on the deceleration of SCA at MLO was elusive according to land-atmosphere CO2 flux estimated by DGVMs and atmospheric inversions. Our results also show the necessity to adequately account for changing circulation patterns in understanding carbon cycle dynamics observed from atmospheric observations and in using these observations to benchmark DGVMs.
17 citations
TL;DR: In this article, the authors derived the first multi-year, monthly resolution N2O emissions from three of the four major EBUSs using high-frequency coastal atmospheric measurements and an inverse method.
Abstract: Eastern Boundary Upwelling Systems (EBUSs) are coastal hotspots of the potent greenhouse gas nitrous oxide (N2O). However, estimates of their emissions suffer from large uncertainties due to their significant spatial and temporal heterogeneity. Here, we derive the first multiyear, monthly resolution N2O emissions from three of the four major EBUSs using high‐frequency coastal atmospheric measurements and an inverse method. We find average combined N2O emissions from the northern California, Benguela, and southern Canary upwelling systems to be 57.7 (51.4–63.9) Gg‐N yr. We also find an offshore region near the Benguela EBUS that exhibits large pulses of emissions with emissions that reach 677 Gg‐N yr in 1 month. Our findings highlight that atmospheric measurements coupled with inverse modeling can capture the large variability in EBUS emissions by quantifying emissions over large spatial distances and over long time periods compared to previous methods using traditional oceanographic measurements. Plain Language Summary Eastern Boundary Upwelling Systems (EBUSs) are important emissions hotspots of marine nitrous oxide to the atmosphere, where it acts as a greenhouse gas and ozone depleting substance. Emissions from the EBUSs are highly episodic, and most previous estimates are snapshots derived from ship‐based measurements. The variability in emissions combined with the sparsity of measurements makes EBUS emission estimates highly uncertain. Here, we use multiyear, near‐continuous atmospheric measurements from coastal stations and an inverse modeling framework to derive emissions from three of the four major EBUSs. Our results quantify the significant spatial and temporal variability in emissions, which is not well‐represented in global studies of marine nitrous oxide emissions.
9 citations