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Michael Brüggemann - One of the best experts on this subject based on the ideXlab platform.
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Erratum zu: Climate Feedback: Wissenschaft kommentiert Journalismus und entwickelt Mehrsystemkompetenz
Publizistik, 2020Co-Authors: Stefanie Walter, Janne Görlach, Michael BrüggemannAbstract:Ein Erratum zu dieser Publikation wurde veröffentlicht: https://doi.org/10.1007/s11616-020-00602-7
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Climate Feedback: Wissenschaft kommentiert Journalismus und entwickelt Mehrsystemkompetenz
Publizistik, 2020Co-Authors: Stefanie Walter, Janne Görlach, Michael BrüggemannAbstract:Science and journalism function according to different logics. From the perspective of systems theory, it is therefore not surprising that scientists see science journalism critically. At the same time, a medialization of science has been observed, meaning that science increasingly takes media logics into account. This exploratory study examines which criteria scientists apply when evaluating journalistic articles and which aspects they praise and criticize. To this end, a qualitative content analysis of comments on the blog Climate Feedback was conducted. We first inductively derived the evaluation criteria applied by the scientists commenting on the news stories and then assigned them to the superordinate categories “journalistic brokerage” and “scientific information performance”. The empirical analysis is based on 82 blog entries and the comments by 184 scientists published between 2015 and 2017. With regard to scientific information performance, we identify seven quality criteria that scientists apply. These are strongly oriented towards the principles that are relevant for the scientists’ own work: Evidence, comprehensiveness, conformity with the scientific state of the art, the proportionality and temporary nature of scientific findings, as well as a logical reasoning. They also demand the recognition of scientific credibility. Scientists evaluate the journalistic performance based on five criteria: Adherence to facts, mediation, the professional approach of the journalist, the contextualization of information, and the diversity of positions and sources. Here, scientists evaluate core competencies of journalists, which are determined by journalistic norms and values. By doing so, the scientists transcend their own system’s boundaries: Not only do they apply criteria relevant to their own system, but they are even more frequently concerned with the journalistic performance. The blog Climate Feedback can be seen as a hybrid organization at the intersection of two systems. It aims to evaluate the quality of the news media coverage by applying the scientific procedure of peer review. In order to enhance the quality of the news media coverage, an internal quality assurance measure is applied to a non-scientific system. Although systems theory takes into account that journalists must be able to identify the relevance of events from the perspective of different systems and that individual actors may well switch between systems depending on the context, the results not only show that competent individuals can switch from one system to another, but that they can simultaneously apply the logics of two different systems. We thus observe the co-existence of quality criteria from the two systems, not a blurring of boundaries between them. The study also provides insights for the medialization approach: The existence of the blog itself can be seen as evidence of medialization. It is the blog’s objective to evaluate influential media reports on Climate change. This is an indicator that the news media coverage is considered relevant for fulfilling the scientific system’s goal. The comments analyzed, however, do not show a one-sided adoption of media logics by scientists. Instead, competent actors at the interface between journalism and science seem to acquire and apply multi-system competence. Wissenschaft und Journalismus beruhen auf unterschiedlichen Logiken. Aus Sicht der Systemtheorie überrascht es also nicht, wenn WissenschaftlerInnen Wissenschaftsjournalismus kritisieren. Gleichzeitig wird aber auch eine Medialisierung von Wissenschaft postuliert. Demnach würde sich Wissenschaft zunehmend an Medienlogiken orientieren. Diese Studie prüft explorativ, welche Kriterien WissenschaftlerInnen bei der Beurteilung journalistischer Artikel heranziehen und welche Aspekte sie loben und kritisieren. Dazu werten wir die Kommentare auf dem Blog „Climate Feedback“ qualitativ inhaltsanalytisch aus. Induktiv werden zunächst die angelegten Evaluationskriterien der WissenschaftlerInnen kategorisiert und dann den Überkategorien „journalistische Vermittlungsleistung“ oder „wissenschaftliche Informationsleistung“ zugeordnet. Unsere Ergebnisse, basierend auf 82 Blogeinträgen und den Kommentaren von 184 WissenschaftlerInnen im Zeitraum von 2015 bis 2017, zeigen, dass sich die WissenschaftlerInnen intensiv und sogar häufiger mit Aspekten der journalistischen als der wissenschaftlichen Leistung beschäftigen. Sie sehen die journalistischen Kriterien eher als erfüllt an, während sie das Fehlen wissenschaftlicher Standards kritisieren. Die beteiligten WissenschaftlerInnen kombinieren die Kommunikationsnormen beider Systeme. Für den Ansatz der Medialisierung von Wissenschaft ergibt sich der Befund, dass die Diffusion von Medienlogiken keineswegs zur Aufgabe von Logiken der Wissenschaft führen muss, sondern dass kompetente Akteure an der Schnittstelle zwischen Journalismus und Wissenschaft Mehrsystemkompetenz erwerben und anwenden können.
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Climate Feedback: Wissenschaft kommentiert Journalismus und entwickelt Mehrsystemkompetenz
Publizistik, 2020Co-Authors: Stefanie Walter, Janne Görlach, Michael BrüggemannAbstract:Wissenschaft und Journalismus beruhen auf unterschiedlichen Logiken. Aus Sicht der Systemtheorie uberrascht es also nicht, wenn WissenschaftlerInnen Wissenschaftsjournalismus kritisieren. Gleichzeitig wird aber auch eine Medialisierung von Wissenschaft postuliert. Demnach wurde sich Wissenschaft zunehmend an Medienlogiken orientieren. Diese Studie pruft explorativ, welche Kriterien WissenschaftlerInnen bei der Beurteilung journalistischer Artikel heranziehen und welche Aspekte sie loben und kritisieren. Dazu werten wir die Kommentare auf dem Blog „Climate Feedback“ qualitativ inhaltsanalytisch aus. Induktiv werden zunachst die angelegten Evaluationskriterien der WissenschaftlerInnen kategorisiert und dann den Uberkategorien „journalistische Vermittlungsleistung“ oder „wissenschaftliche Informationsleistung“ zugeordnet. Unsere Ergebnisse, basierend auf 82 Blogeintragen und den Kommentaren von 184 WissenschaftlerInnen im Zeitraum von 2015 bis 2017, zeigen, dass sich die WissenschaftlerInnen intensiv und sogar haufiger mit Aspekten der journalistischen als der wissenschaftlichen Leistung beschaftigen. Sie sehen die journalistischen Kriterien eher als erfullt an, wahrend sie das Fehlen wissenschaftlicher Standards kritisieren. Die beteiligten WissenschaftlerInnen kombinieren die Kommunikationsnormen beider Systeme. Fur den Ansatz der Medialisierung von Wissenschaft ergibt sich der Befund, dass die Diffusion von Medienlogiken keineswegs zur Aufgabe von Logiken der Wissenschaft fuhren muss, sondern dass kompetente Akteure an der Schnittstelle zwischen Journalismus und Wissenschaft Mehrsystemkompetenz erwerben und anwenden konnen.
Zhengyu Liu - One of the best experts on this subject based on the ideXlab platform.
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A Theory for Bjerknes Compensation: The Role of Climate Feedback
Journal of Climate, 2015Co-Authors: Zhengyu Liu, Haijun Yang, Yingying ZhaoAbstract:AbstractThe response of the atmospheric energy (heat) transport (AHT) to a perturbation oceanic heat transport (OHT) is studied theoretically in a zonal mean energy balance model, with the focus on the effect of Climate Feedback, especially its spatial variation, on Bjerknes compensation (BJC). It is found that the BJC depends critically on Climate Feedback. For a stable Climate, in which negative Climate Feedback is dominant, the AHT always compensates the OHT in the opposite direction. Furthermore, if local Climate Feedback is negative everywhere, the AHT will be weaker than the OHT (undercompensation) because of the damping on the surface oceanic heating through the top-of-atmosphere energy loss. One novel finding is that the compensation magnitude depends on the spatial scale of the forcing and is bounded between a minimum at the global scale and a maximum (of perfect compensation) at small scales. Most interestingly, the BJC is affected significantly by the spatial variation of the Feedback, particul...
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On the Assessment of Nonlocal Climate Feedback. Part I: The Generalized Equilibrium Feedback Assessment*
Journal of Climate, 2008Co-Authors: Zhengyu Liu, Na Wen, Yun LiuAbstract:Abstract A statistical method is developed to assess the full Climate Feedback of nonlocal Climate Feedbacks. The method is a multivariate generalization of the univariate equilibrium Feedback assessment (EFA) method of Frankignoul et al. As a pilot study here, the generalized EFA (GEFA) is applied to the assessment of the Feedback response of sea surface temperature (SST) on surface heat flux in a simple ocean–atmosphere model that includes atmospheric advection. It is shown that GEFA can capture major features of nonlocal Climate Feedback and sheds light on the dynamics of the atmospheric response, as long as the spatial resolution (or spatial degree of freedom) is not very high. Given a sample size, sampling error tends to increase significantly with the spatial resolution of the data. As a result, useful estimates of the Feedback can only be obtained at sufficiently low resolution. The sampling error is also found to increase significantly with the spatial scale of the atmospheric forcing and, in turn...
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on the cause of abrupt vegetation collapse in north africa during the holocene Climate variability vs vegetation Feedback
Geophysical Research Letters, 2006Co-Authors: Yi Wang, Zhengyu Liu, Robert G Gallimore, Michael Notaro, Colin I PrenticeAbstract:The abrupt desertification over the northern Africa in the mid-Holocene is studied in both a complex and a simple coupled Climate-vegetation model. In contrast to the previous mechanism that relies on strong positive vegetation-Climate Feedback and the resulted multiple equilibria, we propose a new mechanism in which the abrupt desertification is caused by low frequency Climate variability, rather than a positive vegetation-Climate Feedback. The implication of this new mechanism to modelling and observation is also discussed.
Tao Zhou - One of the best experts on this subject based on the ideXlab platform.
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global pattern of temperature sensitivity of soil heterotrophic respiration q10 and its implications for carbon Climate Feedback
Journal of Geophysical Research, 2009Co-Authors: Peijun Shi, Tao Zhou, Dafeng Hui, Yiqi LuoAbstract:[1] Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q10 has high spatial heterogeneity. However, most biogeochemical models still use a globally constant Q10 in projecting future Climate change, partly because no spatial pattern of Q10 values has been derived. In this study, we conducted an inverse analysis to retrieve a global pattern of spatially heterogeneous Q10 values by assimilating data of soil organic carbon into a process-based terrestrial carbon model (Carnegie-Ames-Stanford Approach model) at spatial resolution of 1° by 1°. The estimated Q10 values were, in turn, incorporated into soil respiration models to evaluate their impacts on global respiratory carbon release from soil (i.e., total soil respiration is equal to microbial and root respiration) and from microbial decomposition (i.e., heterotrophic respiration). Our results show that the optimized Q10 values are spatially heterogeneous and vary with environmental factors. In general, Q10 value tends to be high in the high-latitudinal regions. The mean Q10 values for different biomes range from 1.43 to 2.03, with the highest value in tundra and the lowest value in deserts. When spatially heterogeneous Q10 values were incorporated into global soil respiration models, simulated soil respiration has a Feedback intensity of 3.21 Pg C °C−1 to Climate warming, which is approximately 40% higher than that with a globally invariant Q10 value. The modeled heterotrophic respiration has a Feedback intensity of 2.26 Pg C °C−1, about 25% higher than that derived from a globally invariant Q10 value. Overall, the Feedback intensity of soil carbon release to Climate warming depends not only on the magnitude of a global mean of Q10 values but also their spatial variability.
Yiqi Luo - One of the best experts on this subject based on the ideXlab platform.
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water scaling of ecosystem carbon cycle Feedback to Climate warming
Science Advances, 2019Co-Authors: Quan Quan, Dashuan Tian, Yiqi Luo, Fangyue Zhang, Thomas W Crowther, Kai Zhu, Han Y H Chen, Qingping ZhouAbstract:It has been well established by field experiments that warming stimulates either net ecosystem carbon uptake or release, leading to negative or positive carbon cycle-Climate change Feedback, respectively. This variation in carbon-Climate Feedback has been partially attributed to water availability. However, it remains unclear under what conditions water availability enhances or weakens carbon-Climate Feedback or even changes its direction. Combining a field experiment with a global synthesis, we show that warming stimulates net carbon uptake (negative Feedback) under wet conditions, but depresses it (positive Feedback) under very dry conditions. This switch in carbon-Climate Feedback direction arises mainly from scaling effects of warming-induced decreases in soil water content on net ecosystem productivity. This water scaling of warming effects offers generalizable mechanisms not only to help explain varying magnitudes and directions of observed carbon-Climate Feedback but also to improve model prediction of ecosystem carbon dynamics in response to Climate change.
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global pattern of temperature sensitivity of soil heterotrophic respiration q10 and its implications for carbon Climate Feedback
Journal of Geophysical Research, 2009Co-Authors: Peijun Shi, Tao Zhou, Dafeng Hui, Yiqi LuoAbstract:[1] Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q10 has high spatial heterogeneity. However, most biogeochemical models still use a globally constant Q10 in projecting future Climate change, partly because no spatial pattern of Q10 values has been derived. In this study, we conducted an inverse analysis to retrieve a global pattern of spatially heterogeneous Q10 values by assimilating data of soil organic carbon into a process-based terrestrial carbon model (Carnegie-Ames-Stanford Approach model) at spatial resolution of 1° by 1°. The estimated Q10 values were, in turn, incorporated into soil respiration models to evaluate their impacts on global respiratory carbon release from soil (i.e., total soil respiration is equal to microbial and root respiration) and from microbial decomposition (i.e., heterotrophic respiration). Our results show that the optimized Q10 values are spatially heterogeneous and vary with environmental factors. In general, Q10 value tends to be high in the high-latitudinal regions. The mean Q10 values for different biomes range from 1.43 to 2.03, with the highest value in tundra and the lowest value in deserts. When spatially heterogeneous Q10 values were incorporated into global soil respiration models, simulated soil respiration has a Feedback intensity of 3.21 Pg C °C−1 to Climate warming, which is approximately 40% higher than that with a globally invariant Q10 value. The modeled heterotrophic respiration has a Feedback intensity of 2.26 Pg C °C−1, about 25% higher than that derived from a globally invariant Q10 value. Overall, the Feedback intensity of soil carbon release to Climate warming depends not only on the magnitude of a global mean of Q10 values but also their spatial variability.
Colin I Prentice - One of the best experts on this subject based on the ideXlab platform.
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latitudinal limits to the predicted increase of the peatland carbon sink with warming
Nature Climate Change, 2018Co-Authors: Angela V Gallegosala, Susan E Page, Steve Moreton, Matthew J Amesbury, Simon Brewer, Dan J. Charman, David W. Beilman, Colin I Prentice, Pierre Friedlingstein, Svante BjorckAbstract:The carbon sink potential of peatlands depends on the balance of carbon uptake by plants and microbial decomposition. The rates of both these processes will increase with warming but it remains unclear which will dominate the global peatland response. Here we examine the global relationship between peatland carbon accumulation rates during the last millennium and planetary-scale Climate space. A positive relationship is found between carbon accumulation and cumulative photosynthetically active radiation during the growing season for mid- to high-latitude peatlands in both hemispheres. However, this relationship reverses at lower latitudes, suggesting that carbon accumulation is lower under the warmest Climate regimes. Projections under Representative Concentration Pathway (RCP)2.6 and RCP8.5 scenarios indicate that the present-day global sink will increase slightly until around ad 2100 but decline thereafter. Peatlands will remain a carbon sink in the future, but their response to warming switches from a negative to a positive Climate Feedback (decreased carbon sink with warming) at the end of the twenty-first century.
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on the cause of abrupt vegetation collapse in north africa during the holocene Climate variability vs vegetation Feedback
Geophysical Research Letters, 2006Co-Authors: Yi Wang, Zhengyu Liu, Robert G Gallimore, Michael Notaro, Colin I PrenticeAbstract:The abrupt desertification over the northern Africa in the mid-Holocene is studied in both a complex and a simple coupled Climate-vegetation model. In contrast to the previous mechanism that relies on strong positive vegetation-Climate Feedback and the resulted multiple equilibria, we propose a new mechanism in which the abrupt desertification is caused by low frequency Climate variability, rather than a positive vegetation-Climate Feedback. The implication of this new mechanism to modelling and observation is also discussed.