Strengthening bottom-up and top-down climate governance

Although the UN and EU focus their climate policies on the prevention of a 2 °C global mean temperature rise, it has been estimated that a rise of at least 4?°C is more likely. Given the political climate of inaction, there is a need to instigate a bottom-up approach so as to build domestic support for future climate treaties, empower citizens, and motivate leaders to take action. A review is provided of the predominant top-down cap-and-trade policies in place – the Kyoto Protocol and EU Emissions Trading Scheme (EU ETS) – with a focus on the grandfathering of emissions entitlements and the possibility of offsetting emissions. These policies are evaluated according to two criteria of justice and it is concluded that they fail to satisfy them. Some suggestions as to how the EU ETS can be improved so as to enable robust climate action are also offered.

Policy relevance

The current supranational climate policy has not been successful and global leaders have postponed the adoption of a meaningful successor to the Kyoto Protocol. In view of this inaction, bottom-up approaches with regard to climate policy should be further developed. It is argued that two of the main top-down policies, grandfathering and offsetting, impede the avowed goals of EU climate policy and pose significant ethical dilemmas with regard to participatory and intergenerational justice. In order to provide a more robust EU climate policy, the EU should inter alia provide a long-term perspective for investors, reduce the volatility of the carbon price, and prepare for the possibility of carbon leakage.     

Insights from trace element geochemistry as to the roles of subduction zone geometry and subduction input on the chemistry of arc magmas

Subduction zones of continental, transitional, and oceanic settings, relative to the nature of the overriding plate, are compared in terms of trace element compositions of mafic to intermediate arc rocks, in order to evaluate the relationship between subduction parameters and the presence of subduction fluids. The continental Chilean Southern Volcanic Zone (SVZ) and the transitional to oceanic Central American Volcanic Arc (CAVA) show increasing degrees of melting with increasing involvement of slab fluids, as is typical for hydrous flux melting beneath arc volcanoes. At the SVZ, the central segment with the thinnest continental crust/lithosphere erupted the highest-degree melts from the most depleted sources, similar to the oceanic-like Nicaraguan segment of the CAVA. The northern part of the SVZ, located on the thickest continental crust/lithosphere, exhibits features more similar to Costa Rica situated on the Caribbean Large Igneous Province, with lower degrees of melting from more enriched source materials. The composition of the slab fluids is characteristic for each arc system, with a particularly pronounced enrichment in Pb at the SVZ and in Ba at the CAVA. A direct compositional relationship between the arc rocks and the corresponding marine sediments that are subducted at the trenches clearly shows that the compositional signature of the lavas erupted in the different arcs carries an inherited signal from the subducted sediments.     

Evaluating Light Availability,Seagrass Biomass,and Productivity Using Hyperspectral Airborne Remote Sensing in Saint Joseph’s Bay,Florida

Seagrasses provide a number of critical ecosystem services, including habitat for numerous species, sediment stabilization, and shoreline protection. Ariel photography is a useful tool to estimate the areal extent of seagrasses, but recent innovations in radiometrically calibrated sensors and algorithm development have allowed identification of benthic types and retrieval of absolute density. This study demonstrates the quantitative ability of a high spatial resolution (1 m) airborne hyperspectral sensor (3.2 nm bandwidth) in the complex coastal waters of Saint Joseph’s Bay (SJB). Several benthic types were distinguished, including submerged and floating aquatic vegetation, benthic red algae, bare sand, and optically deep water. A total of 23.6 km² of benthic vegetation was detected, indicating no dramatic change in vegetation area over the past 30 years. SJB supported high seagrass density at depths shallower than 2 m with an average leaf area index of 2.0?±?0.6 m² m^?2. Annual seagrass production in the bay was 13,570 t C year^?1 and represented 41 % of total marine primary production. The effects of coarser spatial resolution were investigated and found to reduce biomass retrievals, underestimate productivity, and alter patch size statistics. Although data requirements for this approach are considerable, water column optical modeling may reduce the in situ requirements and facilitate the transition of this technique to routine monitoring efforts. The ability to quantify not just areal extent but also productivity of a seagrass meadow in optically complex coastal waters can provide information on the capacity of these environments to support marine food webs.     

PAH transport by sinking particles in the open Mediterranean Sea: a 1 year sediment trap study

One year time series of sinking particles were collected at two depths in the open Mediterranean Sea and analysed for polycyclic aromatic hydrocarbons (PAH). Average total PAH concentrations were 593+/-284 ng g(-1) at 250 m and 551 +/- 198 ng g(-1) at 2850 m. Total PAH fluxes averaged 73 +/- 58 ng m(-2) d(-1) at 250 m and 53 +/- 39 ng m(-2) d(-1) at 2850 m. Contamination levels and, thus, exposure of marine organisms to PAH are comparable in surface and deep waters. Deep waters appear as a significant, yet overlooked, PAH sink. PAH temporal patterns show noticeable seasonality. This is partly due to varying levels of specific components such as the winter increase of pyrolytic PAH. Downward transport processes and the nature of sinking particles also impact on PAH fluxes, as inferred during periods of increasing productivity. Different phase-associations and interactions with particulate organic carbon for low-MW fossil PAH and high-MW pyrolytic PAH influence their downward transport efficiency.     

Book Reviews

The Neolithic revolution in the Near East: Transforming the human landscape. Alan H. Simmons, 2007, The University of Arizona Press, Tucson, Arizona, xvii +339 pp., $55.00 (cloth).     

Emission estimates of methyl chloride from industrial sources in China based on high frequency atmospheric observations

Methyl Chloride (CH₃Cl) is a chlorine-containing trace gas in the atmosphere contributing significantly to stratospheric ozone depletion (Carpenter et al. 2014). In the global CH₃Cl budget, the atmospheric CH₃Cl emissions is predominantly maintained by natural sources, of which magnitudes have been relatively well-constrained. However, significant uncertainties still remain in the CH₃Cl emission strengths from anthropogenic sources. High-frequency and high-precision in situ measurements of atmospheric CH₃Cl concentrations obtained since 2008 at Gosan station (a remote background site in the East Asia) reveal significant pollution events superimposed on the seasonally varying regional background levels. Back trajectory statistics showed that air masses corresponding to the observed CH₃Cl enhancement largely originated from regions of intensive industrial activities in China. Based on an inter-species correlation method, estimates of CH₃Cl emissions from manufacturing industries including coal combustion, use of feedstocks, or process agents in chemical production for China (2008–2012) are 297 ± 71 Gg yr.^?1 in 2008 to 480 ± 99 Gg yr.^?1 in 2009, followed by a gradual decrease of about 25% between 2009 and 2012 (398 ± 92 Gg yr.^?1 for 2010; 286 ± 68 Gg yr.^?1 for 2011; 358 ± 92 Gg yr.^?1 for 2012). The annual average of industrial CH₃Cl emissions for 2008–2012 (363 ± 85 Gg yr.^?1) in China is comparable to the known total global anthropogenic CH₃Cl emissions accounting only for coal combustion and indoor biofuel use. This may suggest that unless emissions from the chemical industry are accounted for, global anthropogenic emissions of CH₃Cl have been substantially underestimated. In particular, since industrial production and use of CH₃Cl have not been regulated under the Montreal Protocol (MP) or its successor amendments, continuous monitoring of Chinese CH₃Cl outflow is important to properly evaluate its anthropogenic emissions.     

Damage evaluation and conservation treatment of the tenth century Korean rock-carved Buddha statues

This study focuses on the lithological characterization, quantitative deterioration assessment and conservation treatment of the tenth century rock-carved Buddha statues in Korea. The Buddha statues were carved on light gray macrocrystalline biotite granite, and features microcline phenocrysts and pegmatite patches. The rock-forming minerals are quartz, plagioclase, microcline and biotite showing micrographic and porphyritic textures. Feldspars and biotite in the host rock have been partly altered into sericite and chlorite by weathering. The surface of the Buddha statues is remarkably irregular due to granular disintegration and the differential weathering of the quartz and microcline. In addition, horizontal and vertical cracks in the host rock have promoted mechanical weathering. Biological colonization of the statues was serious, and featured dark gray and yellowish green lichen, dark green bryophyte and some plants. The Buddha statues were evaluated as the highly weathered rock by ultrasonic survey. The lower parts under the influence of water and areas with severely broken surfaces showed a much more advanced weathering grade. Therefore, scientific conservation treatment was carried out for the long-term maintenance and conservation of the Buddha statues. After pretests, dry, wet and chemical cleanings were applied to the statues. Next, joining of cracked parts and surface consolidating were executed. Finally, the site environment was improved by installation of drain and trimming trees around the statues to ensure more stable long-term conservation.     

29Si and 27Al magic-angle-spinning NMR studies of the thermal transformation of kaolinite

Thermal transformations of kaolinite of different degree of crystallinity have been monitored by ²⁷Al and ²⁹Si high-resolution NMR with magic-angle spinning (MAS NMR), X-ray diffraction, Fourier transform infrared, atomic absorption spectrophotometry and thermogravimetric analysis. NMR shows differences in the dehydroxylation process of kaolinites with different degree of crystallinity and reveals the presence of short-range order in metakaolinite. ²⁹Si NMR spectra acquired with a 30 s recycle delay of poorly and highly crystalline samples heated at 480 and 500° C, respectively, contain three distinct signals; we discuss their assignment in the light of experiments involving leaching of the samples with aqueous KOH. Ca. 40% of Si sites retain their original Q ³ symmetry just above the onset of dehydroxylation and the Q ⁴ environment is present showing that a small amount of amorphous silica has already segregated. The spectrum of samples treated at 1000° C contains a signal at -110ppm (from Q ⁴ silicons) and a faint resonance, from mullite, at ca. -87 ppm. ²⁹Si NMR also shows that cristobalite germs are already present at 950–1000° C. The ²⁷Al MAS NMR spectra of metakaolinite reveal the presence of 4-, 5-and 6-coordinated Al. Changes in the three Al populations as a function of temperature have been monitored quantitatively. Below 800° C, 4-and 5-coordinated Al appears at the expense of 6-coordinated Al, but above 800° C the amount of 6-coordinated Al increases again. We suggest a dehydroxylation scheme which accounts for the presence of 4-and 5 coordinated Al. Above 900–950° C the latter signal is no longer present in the ²⁷Al NMR spectra and new 4-and 6-coordinated Al species (mullite and γ-alumina) appear. We propose new ideas for the structure of metakaolinite.     

Chemical and isotopic compositions of groundwater and stream water in a heavy agricultural basin of Korea

The chemical and isotopic compositions of groundwater and stream water in the Haean basin, Korea, which have been intensively used for agricultural irrigation, were examined. The field parameters and chemical compositions were typical of relatively uncontaminated waters, except for the agricultural impact. The low EC levels indicated that the waters had not experienced any significant geochemical processes such as water-rock interaction and evaporation. The very similar chemical compositions and ionic ratios were also indicative of fast circulation and good hydraulic connection. The oxygen and hydrogen isotopic compositions of most of the samples in wet and dry seasons showed very similar range which indicated a single source for both waters without any significant geochemical alteration. However, in the wet season, evaporation trends were observed in some groundwaters because of inflow of irrigation return flow from a rice paddy field. The isotopes of both waters were affected by the altitude and amount of precipitation.