[en] Over the last decade, many energy experts have supported carbon sequestration as a viable technological response to climate change. Given the potential importance of sequestration in US energy policy, what might explain the views of communities that may be directly impacted by the siting of this technology? To answer this question, we conducted focus groups in two communities who were potentially pilot project sites for California's DOE-funded West Coast Regional Partnership (WESTCARB). We find that communities want a voice in defining the risks to be mitigated as well as the justice of the procedures by which the technology is implemented. We argue that a community's sense of empowerment is key to understanding its range of carbon sequestration opinions, where 'empowerment' includes the ability to mitigate community-defined risks of the technology. This sense of empowerment protects the community against the downside risk of government or corporate neglect, a risk that is rarely identified in risk assessments but that should be factored into assessment and communication strategies.

No abstract available

[en] Forest ecosystems contain large amounts of soil organic carbon (SOC), which is a major component of biogeochemical cycles that may be sensitive to environmental change. We used a combination of nuclear magnetic resonance (NMR) spectroscopy and elemental and isotopic composition to examine the influence of soil properties and climatic factors on the quantity and degree of decomposition of SOC for organic and surface mineral horizons in seven oriental oak (Quercus variabilis Blume) forest sites arranged across a 11^o latitudinal gradient in East China. Lacking Oa horizons, the two southernmost sites contained lower amounts of SOC in the forest floor horizon, but otherwise, latitudinal trends were not consistent. The SOC stock in the 0-10 cm mineral horizon exhibited no clear trend along the gradient and had a negative association with clay + silt content. Based on a higher alkyl/O-alkyl (A/O) ratio and alkyl/methoxyl (A/M) ratio, the SOC at the 0-10 cm depth appeared to be relatively more decomposed in three of the four southern subtropical sites. However, the degree of SOC degradation also decreased strongly with increasing soil pH (R² = 0.90, P = 0.001). Soil organic carbon exhibited increases in δ¹³C and δ¹⁵N and decreases in the C/N ratio with depth for all the seven sites, indicating an increase in its extent of decomposition. Our analysis indicated that the A/M ratio from NMR provided the best indication of the extent of SOC degradation along the latitudinal transect, whereas the elemental and isotopic composition better reflected patterns with soil depth. (author)

No abstract available

[en] Carbon sequestration may be the solution to face our difficulty to cut down the use of fossil energies. CO₂ has to be separated from other gases released by thermal power plants before being stored in deep geological layers, there it can stay as a gas, or it can be dissolved in a fluid phase, or it can react with minerals and be integrated to a solid phase. Oil fields and deep saline water reservoirs are natural candidates for carbon sequestration. Carbon sequestration implies the installation of a network of pipelines to transport CO₂ from the place of production to the place of sequestration. The high cost of carbon sequestration implies the implementation of financial incentives from governments. Some economists foresee a raise of the electricity cost up to 50% if carbon sequestration is used. Other economists see a contradiction: sequestration techniques will not be available in a short term range while numerous thermal power plants are planned to be built in the decade. So carbon sequestration may arrive too late and at a cost that may be not competitive with some renewable energies like off-shore wind energy or thermal solar energy which will be full-grown at that time. (A.C.)

No abstract available

[en] Highlights: • Random Forest analysis combined with SEM to evaluate the abiotic and biotic driving factors effects on vegetation carbon stocks. • Canopy density and forest age were the most crucial driving factors. • Provides new insights into the potential response of subtropical forest ecosystems carbon sequestration to climate change. Subtropical forests play an important role in global carbon cycle and in mitigating climate change. Knowledge on the abiotic and biotic driving factors that affect vegetation carbon stocks in subtropical forest ecosystems is needed to take full advantage of the carbon sequestration potential. We used a large-scale database from national forest continuous inventory in Zhejiang Province, and combined the Random Forest analysis (RF) and structural equation modeling (SEM) to quantify the contribution of biotic and abiotic driving factors on vegetation carbon stocks, and to evaluate the direct and indirect effects of the main driving factors. The RF model explained 50% of the variation in vegetation carbon stocks; canopy density accounted for 17.9%, and forest age accounted for 7.0%. Moreover, the SEM explained 52% of the variation in vegetation carbon stocks; the value of standardized total effects of canopy density and forest age were 0.469 and 0.327, respectively, suggesting that they were the most crucial driving factors of vegetation carbon stocks. Since the forests in our study were relatively young, the forests had a large potential for carbon sequestration. Overall, our study provided new insights into the sensitivity and potential response of subtropical forest ecosystems carbon cycle to climate change.

[en] Carbon sequestration is the option that will make possible to keep fossil energies in the future energy mix. This technology could be used for fixed carbon emission sources like fossil power plants or oil refineries or steel works or cement factories. Today 3 technologies to capture carbon have to be considered: post-combustion, pre-combustion and oxy-combustion, these technologies are expected to be used equally. The second step is the construction of a network of gas pipelines to transport CO₂ to the storage place. The last step is the storage that can be done in ancient oil or natural gas fields or in deep coal layers on in deep salt aquifer. The latter being the most promising. With a carbon emission price comprised between 30 and 50 euros a tonne, carbon sequestration is expected to be economically competitive around 2030 under the condition that the feedback experience gained from the first industrial installations on a large scale have made investment costs drop sharply. Because of its need for important initial investment carbon sequestration appears to be as capitalistic as nuclear energy and will require public funding. Demonstration programs have been launched in Europe, United-States, Canada and Australia. (A.C.)

[en] Current global change policy debate reverberates around the polarized extremes of civilization-level cooperation through treaties as a mitigation tactic, on the one hand, and a wait-and-see approach that may lead to a climatic tragedy of the commons, on the other. Meanwhile, energy technology research is rapidly generating a perception that it will be possible to tune the earth system via carbon sequestration and other types of biogeochemical engineering. The consequences of this potential for planetary management, based on provincial self-interest, include the transition of the earth sciences into a security industry involving proprietary scientific knowledge bases of biogeochemical cycling and the evolution of a climate-design brokerage dominated by military/industrial interests. As the dominant political powers perceive the potential for planetary engineering and consider implementation, the global economy will adjust to exploit new opportunities, perceptions of which will be determined by the quality of system simulations. The growth of a viable international climate-design community will profoundly influence the trajectory of the earth system by providing either the illusion or the reality of predictability. Although this process will be chaotic at first, the probability of stabilization will ultimately be enhanced because the vast resources of the military/industrial sector will become involved. These concepts are disturbingly familiar in that they acknowledge the pervasion of competition and conflict in human technological affairs. However, they are consistent with approaches used in thermodynamics, ecological energetics, behavioral evolution, economics, and interdisciplinary climate science to describe collectively the evolution of the earth system. This paper argues that the perception that the climate can be regulated inexpensively will create an economic driving force for international cartel-style management of the total earth system. That is, the earth system may well become syndicated by those with the resources to effect large-scale management

[en] The presentation covers several new technologies and companies that are making small scale hydrogen with less carbon involved than traditional approaches. Some international activities were also covered