Filters








230 Hits in 1.1 sec

Patterns and controls of inter-annual variability in the terrestrial carbon budget

Barbara Marcolla, Christian Rödenbeck, Alessandro Cescatti
2017 Biogeosciences  
., 2002; Rödenbeck et al., 2003) , or on "bottom-up" methods that rely on data-driven gridded products derived from the upscaling of flux data (Jung et al., 2011 (Jung et al., , 2017 Papale et al., 2015  ...  Maire et al., 2010) and the Jena CarboScope Inversion top-down product, which estimates land (and ocean) fluxes from atmospheric CO 2 concentration measurements and atmospheric transport modelling (Rödenbeck  ... 
doi:10.5194/bg-14-3815-2017 fatcat:7haen325pba5zdfrjuqe73fuby

Patterns and controls of inter-annual variability in the terrestrial Carbon budget

Barbara Marcolla, Christian Rödenbeck, Alessandro Cescatti
2017 Biogeosciences Discussions  
., 2002; Rödenbeck et al., 2003) , or on "bottom-up" methods that rely on data-driven gridded products derived from the upscaling of flux data (Jung et al., 2011 (Jung et al., , 2017 Papale et al., 2015  ...  Maire et al., 2010) and the Jena CarboScope Inversion top-down product, which estimates land (and ocean) fluxes from atmospheric CO 2 concentration measurements and atmospheric transport modelling (Rödenbeck  ... 
doi:10.5194/bg-2017-11 fatcat:6p6wlvbuv5ffnmwybovo4aafcm

Patterns and trends of the dominant environmental controls of net biome productivity

Barbara Marcolla, Mirco Migliavacca, Christian Rödenbeck, Alessandro Cescatti
2020 Biogeosciences  
The Jena CarboScope database can be found at http://www.bgc-jena.mpg.de/CarboScope/ (Rödenbeck et al., 2003) .  ...  Materials and methods Datasets Gridded global flux estimates were obtained from the topdown product Jena CarboScope CO 2 Inversion (version s85_v4.1, 21 atmospheric sites) (Rödenbeck et al., 2003) .  ... 
doi:10.5194/bg-17-2365-2020 fatcat:lxhu3mwnj5cgbeizjgobgyz4y4

The northern European shelf as an increasing net sink for CO2

Meike Becker, Are Olsen, Peter Landschützer, Abdirhaman Omar, Gregor Rehder, Christian Rödenbeck, Ingunn Skjelvan
2021 Biogeosciences  
the Rödenbeck et al. pCO 2 just ignore land barriers.  ...  Average regional differences between MLR 1 and gridded SOCAT v5 data, the Rödenbeck map and gridded SOCAT v5 data, MLR 1 and the Rödenbeck map, and MLR 3 and the gridded SOCAT v5 data (from left to right  ... 
doi:10.5194/bg-18-1127-2021 fatcat:julx7w2qpfbo7jj3d27y3kq5du

Can the envisaged reductions of fossil fuel CO2 emissions be detected by atmospheric observations?

Ingeborg Levin, Christian Rödenbeck
2007 Die Naturwissenschaften  
anthropogenic "disturbance" is superimposed on relatively large and strongly variable natural fluxes of CO 2 between the atmosphere, the terrestrial biosphere, and the oceans (Bousquet et al. 2000; Rödenbeck  ... 
doi:10.1007/s00114-007-0313-4 pmid:17938872 pmcid:PMC2755783 fatcat:db6nons5zvanpdpyk3jvfviitu

On evaluating ocean models with atmospheric potential oxygen

Tobias Naegler, Philippe Ciais, James C. Orr, Olivier Aumont, Christian Rödenbeck
2007 Tellus: Series B, Chemical and Physical Meteorology  
A B S T R A C T We used observed and simulated atmospheric potential oxygen (APO) to evaluate simulated air-sea flux fields from 11 ocean global carbon cycle models. APO is defined in terms of atmospheric CO 2 , O 2 and N 2 so as not to depend on terrestrial photosynthesis and respiration. Hence, it is in principal suited to evaluate simulated air-sea fluxes of these gases. We forced two different atmospheric transport models, TM2 and TM3, with simulated air-sea fluxes from each of the 11 ocean
more » ... models, and we compared resulting simulated latitudinal and seasonal variations in APO with observations. Differences between the two atmospheric transport models, which offer a first estimate of uncertainty due to atmospheric transport, are similar in magnitude to the average model-data differences and to the spread between the ocean models. Simulated annual mean meridional APO profiles qualitatively resemble the observations, although at individual stations there remain substantial differences between models and observations. The simulated amplitude of the seasonal APO variability was generally less than observed. We conclude that it is difficult to validate ocean models based on APO because shortcomings in atmospheric transport models and problems with data representativity cannot be distinguished from ocean model deficiencies.
doi:10.3402/tellusb.v59i1.16975 fatcat:zwsfmpsvfjgilhow4s4pdhzv7m

Abrupt seasonal transitions in land carbon uptake in 2015

Chao Yue, Philippe Ciais, Ana Bastos, Frederic Chevallier, Yi Yin, Christian Rödenbeck
2017 Atmospheric Chemistry and Physics Discussions  
, 2005; Rödenbeck et al., 73 2003).  ...  ., , 2010 Rödenbeck, 2005; Rödenbeck et al., 2003) . We focus on seasonal patterns in the land carbon 61 uptake during 2015, relative to the long-term trend of 1981-2015.  ... 
doi:10.5194/acp-2016-1167 fatcat:bika3lqpfza2feqiz7dsyqn5jy

Stochastic modelling: replacing fast degrees of freedom by noise

Wolfram Just, Holger Kantz, Christian Rödenbeck, Mario Helm
2001 Journal of Physics A: Mathematical and General  
In systems with timescale separation, where the fast degrees of freedom exhibit chaotic motion, the latter are replaced by suitable stochastic processes. A projection technique is employed to derive equations of motion for the phase space density of the slow variables by eliminating the fast ones. The resulting equations can be approximated in a controlled way by Fokker-Planck equations or equivalently by stochastic differential equations for slow degrees of freedom. We discuss some model
more » ... ions and explore the accuracy of the approximations by numerical simulations.
doi:10.1088/0305-4470/34/15/302 fatcat:didm2qufofa7fp2tfuipvixtya

Decadal variability in land carbon sink efficiency

Lei Zhu, Philippe Ciais, Ana Bastos, Ashley P. Ballantyne, Frederic Chevallier, Thomas Gasser, Masayuki Kondo, Julia Pongratz, Christian Rödenbeck, Wei Li
2021 Carbon Balance and Management  
Background The climate mitigation target of limiting the temperature increase below 2 °C above the pre-industrial levels requires the efforts from all countries. Tracking the trajectory of the land carbon sink efficiency is thus crucial to evaluate the nationally determined contributions (NDCs). Here, we define the instantaneous land sink efficiency as the ratio of natural land carbon sinks to emissions from fossil fuel and land-use and land-cover change with a value of 1 indicating carbon
more » ... ality to track its temporal dynamics in the past decades. Results Land sink efficiency has been decreasing during 1957–1990 because of the increased emissions from fossil fuel. After the effect of the Mt. Pinatubo eruption diminished (after 1994), the land sink efficiency firstly increased before 2009 and then began to decrease again after 2009. This reversal around 2009 is mostly attributed to changes in land sinks in tropical regions in response to climate variations. Conclusions The decreasing trend of land sink efficiency in recent years reveals greater challenges in climate change mitigation, and that climate impacts on land carbon sinks must be accurately quantified to assess the effectiveness of regional scale climate mitigation policies.
doi:10.1186/s13021-021-00178-3 pmid:33973052 fatcat:7kfo2xom2nhmzlpacxcrtfy45y

Background reduction at the KATRIN experiment by the shifted analysing plane configuration [article]

Alexey Lokhov, Benedikt Bieringer, Guido Drexlin, Stephan Dyba, Kevin Gauda, Florian Fränkle, Ferenc Glück, Volker Hannen, Dominic Hinz, Susanne Mertens, Caroline Rodenbeck, Anna Schaller (+1 others)
2022 arXiv   pre-print
The KATRIN experiment aims at measuring the electron neutrino mass with a sensitivity of 0.2 eV/c^2 after five years of data taking. Recently a new upper limit for the neutrino mass of 0.8 eV/c^2 (90 reach the design sensitivity, a reduction of the background rate by one order of magnitude is required. The shifted analysing plane (SAP) configuration exploits a specific shaping of the electric and magnetic fields in the KATRIN main spectrometer to reduce the spectrometer background by a factor
more » ... two. We discuss the general idea of the SAP configuration and describe the main features of this novel measurement mode.
arXiv:2201.11743v1 fatcat:cnoxy6trezcdxiccpmkjpvun7y

How does the terrestrial carbon exchange respond to interannual climatic variations? A quantification based on atmospheric CO2 data

Christian Rödenbeck, Sönke Zaehle, Ralph Keeling, Martin Heimann
2018 Biogeosciences Discussions  
This notion is supported by the finding that the NEE-T inversion possesses predictive skill on the time scale of El Niño / Southern Oscillation (Rödenbeck et al., 2018) .  ...  Ocean fluxes are fixed to the flux estimates oc_v1.5 (update of Rödenbeck et al., 2014) based on an interpolation of pCO 2 data from the SOCATv5 data base (Bakker et al., 2016) .  ... 
doi:10.5194/bg-2018-34 fatcat:yvljrdo5u5baffjuz6wigiu4ye

How does the terrestrial carbon exchange respond to inter-annual climatic variations? A quantification based on atmospheric CO2 data

Christian Rödenbeck, Sönke Zaehle, Ralph Keeling, Martin Heimann
2018 Biogeosciences  
et al. (2018 Rödenbeck et al. ( ) for runs over 1957 .  ...  Method The standard inversion As a starting point, we use the existing Bayesian atmospheric CO 2 inversion implemented in the Jena CarboScope, run s85oc_v4.1s (update of Rödenbeck et al., 2003; Rödenbeck  ... 
doi:10.5194/bg-15-2481-2018 fatcat:2vrifzzaovc3pjnrwtjrrjuvfq

Impacts of ENSO on air-sea oxygen exchange: Observations and mechanisms

Yassir A. Eddebbar, Matthew C. Long, Laure Resplandy, Christian Rödenbeck, Keith B. Rodgers, Manfredi Manizza, Ralph F. Keeling
2017 Global Biogeochemical Cycles  
This underestimate is in agreement with a previous comparison of the atmospheric inversion APO results to an earlier generation ocean model [Rödenbeck et al., 2008] .  ...  We evaluate the contributions of F O2 and F CO2 to APO variability, by computing the air-sea flux of APO (F APO ), following Rödenbeck et al. [2008] , as F APO ¼ F O2 þ 1:1ÁF CO2 À X O2 X N2 F N2 ; (3  ... 
doi:10.1002/2017gb005630 fatcat:l7zvtwozwvfndl2lssyeabpd2e

FLUXNET and modelling the global carbon cycle

ANDREW D. FRIEND, ALMUT ARNETH, NANCY Y. KIANG, MARK LOMAS, JÉRÔME OGÉE, CHRISTIAN RÖDENBECK, STEVEN W. RUNNING, JEAN-DIEGO SANTAREN, STEPHEN SITCH, NICOLAS VIOVY, F. IAN WOODWARD, SÖNKE ZAEHLE
2007 Global Change Biology  
Rödenbeck et al., 2003) . However, the inversion technique cannot directly attribute these signals to mechanisms.  ...  In Rödenbeck et al. (2003) , a priori information consisted of statistics of anthropogenic emissions from fossil fuel burning and cement manufacturing (Olivier & Berdowski, 2001) , climatological NEE  ... 
doi:10.1111/j.1365-2486.2006.01223.x fatcat:vpqe2kbnvvftnab7e5s7h3lm3y

The reinvigoration of the Southern Ocean carbon sink

Peter Landschützer, Nicolas Gruber, F. Alexander Haumann, Christian Rödenbeck, Dorothee C. E. Bakker, Steven van Heuven, Mario Hoppema, Nicolas Metzl, Colm Sweeney, Taro Takahashi, Bronte Tilbrook, Rik Wanninkhof
2015 Science  
The mixed-layer scheme and inversion data supporting the main findings can be obtained from www.bgc-jena.mpg.de/~christian. roedenbeck/download-CO2-ocean/ and www.bgc-jena.mpg.de/ christian.roedenbeck/  ... 
doi:10.1126/science.aab2620 pmid:26359401 fatcat:mmbm7bycxbb3fbyqq2jcio3jf4
« Previous Showing results 1 — 15 out of 230 results