Can developed economies combat dangerous anthropogenic climate change without near-term reductions from developing economies?

Developing economy greenhouse gas emissions are growing rapidly relative to developed economy emissions (Boden et al. 2010) and developing economies as a group have greater emissions than developed economies. These developments are expected to continue (U.S. Energy Information Administration 2010), which has led some to question the effectiveness of emissions mitigation in developed economies without a commitment to extensive mitigation action from developing economies. One often heard argument against proposed U.S. legislation to limit carbon emissions to mitigate climate change is that, without participation from large developing economies like China and India, stabilizing temperature at 2 degrees Celsius above preindustrial (United Nations 2009), or even reducing global emissions levels, would be impossible (Driessen 2009; RPC Energy Facts 2009) or prohibitively expensive (Clarke et al. 2009). Here we show that significantly delayed action by rapidly developing countries is not a reason to forgo mitigation efforts in developed economies. This letter examines the effect of a scenario with no explicit international climate policy and two policy scenarios, full global action and a developing economy delay, on the probability of exceeding various global average temperature changes by 2100. This letter demonstrates that even when developing economies delay any mitigation efforts until 2050 the effect of action by developed economies will appreciably reduce the probability of more extreme levels of temperature change. This paper concludes that early carbon mitigation efforts by developed economies will considerably affect the distribution over future climate change, whether or not developing countries begin mitigation efforts in the near term.     

Comparison of rates of ureolysis between Sporosarcina pasteurii and an indigenous groundwater community under conditions required to precipitate large volumes of calcite

Ureolysis-driven calcite precipitation has potential to seal porosity and fracture networks in rocks thus preventing groundwater flow and contaminant transport. In this study urea hydrolysis and calcite precipitation rates for the model bacterium Sporosarcina pasteurii were compared with those of indigenous groundwater communities under conditions required to precipitate large volumes of calcite (up to 50 g L⁻¹). We conducted microcosm experiments in oxic artificial and anoxic natural groundwaters (collected from the Permo-Triassic sandstone aquifer at Birmingham, UK) that were inoculated with aerobically grown S. pasteurii. The rate constants for urea hydrolysis, k_urea, ranged between 0.06 and 3.29 d⁻¹ and were only affected by inoculum density. Higher Ca²⁺ concentration (50-500 mM Ca²⁺) as well as differences in fO₂ did not inhibit the ureolytic activity of S. pasteurii and did not significantly impact k_urea. These results demonstrate that S. pasteurii has potential to improve calcite precipitation in both oxic and anoxic groundwaters, especially if indigenous communities lack ureolytic activity. Urea hydrolysis by indigenous groundwater communities was investigated in anoxic, natural groundwaters amended with urea and CaCl₂. A notable increase in ureolysis rates was measured only when these communities were stimulated with dilute nutrients (with best results from blackstrap molasses). Furthermore, there was a considerable lag time (12-20 days) before ureolysis and calcite precipitation began. Calculated ureolysis rate constants, k_urea, ranged between 0.03 and 0.05 d⁻¹ and were similar to k_urea values produced by S. pasteurii at low inoculum densities. Overall, this comparative study revealed that the growth of ureolytic microorganisms present within groundwaters can easily be stimulated to enhance rates of urea hydrolysis in the subsurface, and thus can be used to induce calcite precipitation in these environments. The time required for urea hydrolysis to begin is almost instantaneous if an inoculum of S. pasteurii is included, while it may take several weeks for ureolytic groundwater communities to grow and become ureolytically active.     

Freshwater control of ice-rafted debris in the last glacial period at Mono Lake, California, USA

The type section silts of the late Pleistocene Wilson Creek Formation at Mono Lake contain outsized clasts, dominantly well-rounded pebbles and cobbles of Sierran lithologies. Lithic grains > 425 μm show a similar pattern of variability as the > 10 mm clasts visible in the type section, with decreasing absolute abundance in southern and eastern outcrops. The largest concentrations of ice-rafted debris (IRD) occur at 67–57 ka and 46–32 ka, with strong millennial-scale variability, while little IRD is found during the last glacial maximum and deglaciation.Stratigraphic evidence for high lake level during high IRD intervals, and a lack of geomorphic evidence for coincidence of lake and glaciers, strongly suggests that rafting was by shore ice rather than icebergs. Correspondence of carbonate flux and IRD implies that both were mainly controlled by freshwater input, rather than disparate non-climatic controls. Conversely, the lack of IRD during the last glacial maximum and deglacial highstands may relate to secondary controls such as perennial ice cover or sediment supply. High IRD at Mono Lake corresponds to low glacial flour flux in Owens Lake, both correlative to high warm-season insolation. High-resolution, extra-basinal correlation of the millennial peaks awaits greatly improved age models for both records.     

服务全球生物多样性和食物安全的可再生氮利用优先选择（英文）

The continuing use of petrochemicals in mineral nitrogen(N) production may be affected by supply or cost issues and climate agreements.Without mineral N,a larger area of cropland is required to produce the same amount of food,impacting biodiversity.Alternative N sources include solar and wind to power the Haber-Bosch process,and the organic options such as green manures,marine algae and aquatic azolla.Solar power was the most land-efficient renewable source of N,with using a tenth as much land as wind energy,and at least 100 th as much land as organic sources of N.In this paper,we developed a decision tree to locate these different sources of N at a global scale,or the first time taking into account their spatial footprint and the impact on terrestrial biodiversity while avoiding impact on albedo and cropland,based on global resource and impact datasets.This produced relatively few areas suitable for solar power in the western Americas,central southern Africa,eastern Asia and southern Australia,with areas most suited to wind at more extreme latitudes.Only about 2% of existing solar power stations are in very suitable locations.In regions such as coastal north Africa and central Asia where solar power is less accessible due to lack of farm income,green manures could be used,however,due to their very large spatial footprint only a small area of low productivity and low biodiversity was suitable for this option.Europe in particular faces challenges because it has access to a relatively small area which is suitable for solar or wind power.If we are to make informed decisions about the sourcing of alternative N supplies in the future,and our energy supply more generally,a decision-making mechanism is needed to take global considerations into account in regional land-use planning.     

Stuck in transition? Exploring the spaces of employment training for youth with intellectual disability

This paper is concerned with the experiences of young adults with intellectual disabilities as they transition from high school in search of paid employment. The experiences of people with intellectual disability remain under-researched within geography. We use qualitative techniques to examine the experiences of six young adults with intellectual disabilities. Data are drawn from interviews with the youth themselves, their parents, and employers, as well as from participant observation at an employment training program for the intellectually disabled. While the primary goal of the youth and their parents was to make a transition to competitive paid work, a lack of transition planning, a shortage of appropriate opportunities and other factors meant the youth spent considerable time in ‘transitional spaces’ such as the vocational training centre, sheltered workshop, and supported employment placements. While these spaces are organized around an explicitly economic goal of augmenting the youth’s employability, they can play a critical role as spaces for social interaction and meaningful activity outside the home. Study findings point to the importance of moving beyond paid employment as the core of a successful transition to consider a broader goal of ‘meaningful activity’.     

Advancing tsunami risk assessment by improving spatio-temporal population exposure and evacuation modeling

Tsunamis are among the most destructive and lethal of coastal hazards. These are time-specific events, and despite directly affecting a narrow strip of coastline, a single occurrence can have devastating effects and cause massive loss of life, especially in urbanized coastal areas. In this work, in order to consider the time dependence of population exposure to tsunami threat, the variation of spatio-temporal population distribution in the daily cycle is mapped and analyzed in the Lisbon Metropolitan Area. High-resolution daytime and nighttime population distribution maps are developed using ‘intelligent dasymetric mapping,’ that is, applying areal interpolation to combine best-available census data and statistics with land use and land cover data. Workplace information and mobility statistics are considered for mapping daytime distribution. In combination with a tsunami hazard map, information on infrastructure, land use and terrain slope, the modeled population distribution is used to assess people’s evacuation speed, applying a geospatial evacuation modeling approach to the city of Lisbon. The detailed dynamic population exposure assessment allows producing both daytime and nighttime evacuation time maps, which provide valuable input for evacuation planning and management. Results show that a significant amount of population is at risk, and its numbers increase dramatically from nighttime to daytime, especially in the zones of high tsunami flooding susceptibility. Also, full evacuation can be problematic in the daytime period, even if initiated immediately after a major tsunami-triggering earthquake. The presented approach greatly improves tsunami risk assessment and can benefit all phases of the disaster management process.     

Linking pattern to process in reef sediment dynamics at Lady Musgrave Island,southern Great Barrier Reef

Linking surficial sediment patterns in reef environments to the processes that underlie their depositional dynamics enables predictions to be made of how environmental changes will influence reef‐associated sedimentary landforms, such as islands and beaches. Geomorphic linkages between sediment deposition patterns and the biophysical processes that drive them are often poorly resolved, particularly at broad landscape scales where tangible statements can be made about structural changes to landforms. The present study applies geospatial techniques to link patterns in reef sediment dynamics at Lady Musgrave Island to the underlying processes driving them. In situ calcification is characterized by developing a high resolution map of the surficial calcium carbonate producing communities inhabiting the reef platform, and associated sediments across the reef flat are analysed for grain size, kurtosis, sorting and threshold bed shear stress to explore transport pathways across the reef flat and lagoon. Wave energy is modelled across the entire reef platform as a potential driver of sediment dynamics, and morphometric linkages are empirically defined between wave energy and grain size. Findings indicate that carbonate sediments are primarily sourced from calcifying communities colonizing the outer periphery of the reef platform and that sediment grain size can be reliably linked to wave energy by virtue of a linear model.     

Environmental integrity of international carbon market mechanisms under the Paris Agreement

The Paris Agreement establishes provisions for using international carbon market mechanisms to achieve climate mitigation contributions. Environmental integrity is a key principle for using such mechanisms under the Agreement. This paper systematically identifies and categorizes issues and options to achieve environmental integrity, including how it could be defined, what influences it, and what approaches could mitigate environmental integrity risks. Here, environmental integrity is assumed to be ensured if the engagement in international transfers of carbon market units leads to the same or lower aggregated global emissions. Four factors are identified that influence environmental integrity: the accounting for international transfers; the quality of units generated, i.e. whether the mechanism ensures that the issuance or transfer of units leads to emission reductions in the transferring country; the ambition and scope of the mitigation target of the transferring country; and incentives or disincentives for future mitigation action, such as possible disincentives for transferring countries to define future mitigation targets less ambitiously or more narrowly in order to sell more units. It is recommended that policy-makers combine several approaches to address the significant risks to environmental integrity.

Key policy insights

• Robust accounting is a key prerequisite for ensuring environmental integrity. The diversity of nationally determined contributions is an important challenge, in particular for avoiding double counting and for ensuring that the accounting for international transfers is representative for the mitigation efforts by Parties over time.

• Unit quality can, in theory, be ensured through appropriate design of carbon market mechanisms; in practice, existing mechanisms face considerable challenges in ensuring unit quality. Unit quality could be promoted through guidance under Paris Agreement Article 6, and reporting and review under Article 13.

• The ambition and scope of mitigation targets is key for the incentive for transferring countries to ensure unit quality because countries with ambitious and economy-wide targets would have to compensate for any transfer of units that lack quality. Encouraging countries to adopt ambitious and economy-wide NDC targets would therefore facilitate achieving environmental integrity.

• Restricting transfers in instances of high environmental integrity risk – through eligibility criteria or limits – could complement these approaches.

     

Ecological assessment to detect imminent change in coral reefs of Admiral Cockburn Land and Sea National Park,Turks and Caicos Islands

Coral reefs of the Turks and Caicos Islands (TCIs) (Caribbean Sea) constitute some of the few pristine coral reef systems in the world and play a crucial role in the islands’ economy because they support rich fisheries catches and tourism development. Ambitious development plans involving increase in fishing and tourism pressures are about to bring changes in coastal zone resources of the TCIs associated with increased sediments and nutrients and reduced predation by herbivorous fish on coral reefs. Understanding change is critical when attempting to protect the resources that these coral reefs support and to adopt proper management strategies. Yet, an environmental assessment program to detect imminent human‐induced changes on the surrounding reefs of the TCIs is lacking. Thus, (i) we obtained baseline data on benthic composition and coral community structure at seven reef sites of representative reefs of the TCIs within the Admiral Cockburn Land and Sea National Park (ACLSNP) of South Caicos Island and (ii) performed a priori statistical power analysis to calculate replication requirements for safely and confidently detecting small (δ = 0.1), medium (δ = 0.3), and large (δ = 0.5) effect sizes for a number of relevant to anticipated changes, univariate, benthic indices and for power β = 0.95. The platforms of the margin reefs studied (9–12 m depth) appeared rather variable regarding benthic composition but quite homogeneous regarding hard coral community structure. Mean percent cover of algal functional groups was 0.1 ± 0.3 (mean ± sd) percent for coralline algae and Halimeda, 0.1 ± 0.6 (mean ± sd) percent for macroalgae, 21.7 ± 33 (mean ± sd) percent for turf algae and 4.8 ± 4.0 (mean ± sd) percent for hard coral cover. The dominant benthic component, however, was carbonate substrate (mean ± sd = 30.4 ± 34.3), thus indicating an accreting reef framework. Mean hard coral density, colony size and recruit density were 5.5 ± 1.8 (mean ± sd) corals per 20‐m line transect, 13.0 ± 2.3 (mean ± sd) cm maximum colony diameter, and 1.3 ± 1.4 (mean ± sd) recruits per square foot, respectively. Due to high natural variance, hard coral colony size and density were practically the most sensitive indices in detecting even small size changes on benthos. Also, the geometric mean of log‐transformed colony size‐frequency distributions of the most abundant hard coral taxa, i.e. Montastrea annularis, Agaricia spp., Siderastrea spp. and Porites asteroides were practically sensitive for the same purpose. We hope that the study will optimize the spatial component of a necessary environmental impact assessment program on coral reefs of the TCIs once the natural spatial variability of the system has been assessed and sensitive, benthic, univariate indices have been identified for representative reference coral reef sites of the TCIs.