Sources and pathways of Sr in the North Atlantic–Arctic region: present day and global warming

The spatial and temporal distributions of the anthropogenic radionuclides ¹³⁷Cs and ⁹⁰Sr, originating from nuclear bomb testing, the Sellafield reprocessing plant in the Irish Sea (UK), and from the Ob and Yenisey river discharges to the Arctic Ocean, have been simulated using the global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). The physical model is forced with daily atmospheric re-analysis fields for the period of 1948–1999. Comparison of the temporal evolution of the observed and the simulated concentrations of ⁹⁰Sr has been performed in the Kara Sea. The relative contributions of the different sources on the temporal and spatial distributions of the surface ⁹⁰Sr are quantified over the simulated period. It follows that the Ob river discharge dominated the surface ⁹⁰Sr over most of the Arctic Ocean and along the eastern and western coasts of Greenland before 1960. During the period of 1980–1990, the atmospheric fallout and the Ob river discharge were equally important for the ⁹⁰Sr distribution in the Arctic Ocean. Furthermore, an attempt has been made to explore the possible dispersion of accidental released ⁹⁰Sr from the Ob and Yenisey rivers under a global warming scenario (2 × CO₂). The difference between the present-day and the global warming scenario runs indicates that more of the released ⁹⁰Sr from the Ob and Yenisey rivers is confined to the Arctic Ocean in the global warming run, particularly in the near coastal, non-European part of the Arctic Ocean.     

Impact of global warming on agricultural product markets: stochastic world food model analysis

Climatic change through global warming and drought is a major issue for agricultural production. Most researchers who discuss the effects of such changes on agriculture report estimated yield changes based on crop process models. However, studies focusing on the impact of climatic change on agricultural product markets are very rare. This paper examines the relationship between climatic change and world food markets, i.e., the supply and demand of crops, by using a stochastic version of a world food model, the International Food and Agricultural Policy Simulation Model. The results suggest that variations in the production of maize and soybeans in some major producing countries will be large, and variations in the producer prices of all crops will increase. Countries that suffer higher price risk because of high sensitivity to temperature fluctuations may need to consider changes in cropping patterns.     

Arsenic and Mn levels in Isaza (Gymnogobius isaza) during the mass mortality event in Lake Biwa, Japan

The present study measured the concentrations of 25 elements (Li, Mg, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) in the whole body of Isaza which is an endemic fish species to Lake Biwa, Japan, and compared the values in the specimens from the mass mortality Isaza (MMI) and normal fresh Isaza (NFI). The mean levels of Mn and total As (T-As) were relatively higher in MMI than in NFI. In the T-As, highly toxic inorganic As was detected in MMI. Moreover we found Mn and As concentrations in surface sediment were extremely high and temporally increased. From all these results, we could infer that the dissolution of Mn and As from surface sediment of Lake Biwa might have been one of the cause for the mass mortality of Isaza.     

Modeling biogeochemical processes of phosphorus for global food supply

Harvests of crops, their trade and consumption, soil erosion, fertilization and recycling of organic waste generate fluxes of phosphorus in and out of the soil that continuously change the worldwide spatial distribution of total phosphorus in arable soils. Furthermore, due to variability in the properties of the virgin soils and the different histories of agricultural practices, on a planetary scale, the distribution of total soil phosphorus is very heterogeneous. There are two key relationships that determine how this distribution and its change over time affect crop yields. One is the relationship between total soil phosphorus and bioavailable soil phosphorus and the second is the relationship between bioavailable soil phosphorus and yields. Both of these depend on environmental variables such as soil properties and climate. We propose a model in which these relationships are described probabilistically and integrated with the dynamic feedbacks of P cycling in the human ecosystem. The model we propose is a first step towards evaluating the large-scale effects of different nutrient management scenarios. One application of particular interest is to evaluate the vulnerability of different regions to an increased scarcity in P mineral fertilizers. Another is to evaluate different regions’ deficiency in total soil phosphorus compared with the level at which they could sustain their maximum potential yield without external mineral inputs of phosphorus but solely by recycling organic matter to close the nutrient cycle.     

Nitrogen dynamics of a mountain forest on dolomitic limestone--a scenario-based risk assessment

The dominant nitrogen (N) fluxes were simulated in a mountain forest ecosystem on dolomitic bedrock in the Austrian Alps. Based on an existing small-scale climate model the simulation encompassed the present situation and a 50-yr projection. The investigated scenarios were current climate, current N deposition (SC1) and future climate (+2.5 degrees C and +10% annual precipitation) with three levels of N deposition (SC2, 3, 4). The microbially mediated N transformation, including the emission of nitrogen oxides, was calculated with PnET-N-DNDC. Soil hydrology was calculated with HYDRUS and was used to estimate the leaching of nitrate. The expected change of the forest ecosystem due to changes of the climate and the N availability was simulated with PICUS. The incentive for the project was the fact that forests on dolomitic limestone stock on shallow Rendzic Leptosols that are rich in soil organic matter are considered highly sensitive to the expected environmental changes. The simulation results showed a strong effect due to increased temperatures and to elevated levels of N deposition. The outflux of N, both as nitrate (6-25kg Nha(-1)yr(-1)) and nitrogen oxides (1-2kg Nha(-1)yr(-1)), from the forest ecosystem are expected to increase. Temperature exerts a stronger effect on the N(2)O emission than the increased rate of N deposition. The main part of the N emission will occur as N(2) (15kg Nha(-1)yr(-1)). The total N loss is partially offset by increased rates of N uptake in the biomass due to an increase in forest productivity.     

Matching mechanism in global public goods games: a case of climate protection

In the setting of dealing with climate change, this article designs a matching mechanism for global public goods provision with the aggregative game approach. Given endowment and the technology of each country, we propose the conditions under which the matching mechanism is able to guarantee full participation and Pareto efficient provision, respectively, in the cases with certain and uncertain preference information. These conditions cannot only be adopted in international negotiation and cooperation, but also refines the theory of matching game. In comparative static analyses, we discover that: First, changes of initial stock of climate goods produce a wealth effect and the crowd-out effect is less than 1. Second, climate tax policies affect the supply and welfare of each country only when they produce wealth effects, and if tax revenue is transferred into climate goods with more advanced technology, they will produce positive wealth effects. Third, modifying matching plans dynamically and appropriately can urge countries to improve technology, and especially given a Pareto optimal mechanism, adjusting the matching plan to keep marginal rates of transformation unchanged as technology changes is still able to ensure full participation and efficient supply of climate goods.     

Addressing concerns about climate policies: the possibilities and perils of responsive accommodation

Responsive accommodation is a political strategy that addresses concerns about a policy proposal by incorporating amendments that address those concerns. This approach can broaden the policy’s appeal, but is strategically risky, as it can alienate the policy’s base of support. We examine this strategy and its application in the politics of climate change. Using a novel survey experiment, relative public support is evaluated for two amendments to a carbon tax proposal – revenue neutrality assurances and a carbon tariff – designed to ease concerns about taxes and global competitiveness. Analysis shows that support for a carbon tax increases when coupled with a carbon tariff, but decreases among some of the policy’s supporters when described as revenue-neutral. These results suggest that policymakers using a responsive accommodation strategy must carefully weigh its possible risks and rewards in their particular context.     

Media Use and Public Perceptions of Global Warming in India

Media plays a vital role in informing the public about environmental threats. Although climate change is a global problem, developing countries such as India are often more vulnerable to the impacts due to poverty, illiteracy, and low public awareness. Using data from a nationally representative survey in India, this paper explores the relationships between media use, issue attention, and trust in informational sources on one hand and science-based climate change beliefs, risk perceptions, and policy support on the other. Results suggest that the Indian media, through consistent and accurate coverage of global warming using trusted sources, can play a positive role in increasing public engagement among a largely unaware population. Implications for climate change communication in India are discussed.     

Gender differences in wayfinding in virtual environments with global or local landmarks

This study assesses gender differences in wayfinding in environments with global or local landmarks by analyzing both overall and fine-grained measures of performance. Both female and male participants were required to locate targets in grid-like virtual environments with local or global landmarks. Interestingly, the results of the two overall measures did not converge: although females spent more time than males in locating targets, both genders were generally equivalent in terms of corrected travel path. Fine-grained measures account for different aspects of wayfinding behavior and provide additional information that explains the divergence in overall measures; females spent less time traveling away from the target location, a higher proportion of time not traversing, and made more rotations when stopping than males did. Rather than unequivocally supporting male superiority in wayfinding tasks, both the overall and fine-grained measures partially indicate that males and females are differentially superior when using global and local landmark information, respectively. To summarize, males moved faster than females but did not necessarily navigate the spatial surroundings more efficiently. Each gender showed different strengths related to wayfinding; these differences require the application of both overall and fine-grained measures for accurate assessment.     

Landscape–seascape dynamics in the isthmus between S?rkapp Land and the rest of Spitsbergen: Will a new big Arctic island form?

Transformation of the glaciated isthmus between Sørkapp Land and the rest of Spitsbergen since 1900 is described. The landscape–seascape dynamics depends on the glacial recession determined by climate warming after the Little Ice Age (i.e., since the beginning of the twentieth century, and especially since the 1980s). The isthmus has been narrowed from 28 km in 1899–1900 to 6.2 km in 2013, and lowered by 60–200 m from 1936 to 2005. Two isthmus’ glaciers will have melted, given the current thermic conditions, by 2030–2035. It cannot be ruled out that Sørkapp Land will become an island after that period, because the altitude of the glaciers’ bedrock is close to the sea level. The disappearance of this huge ice mass, even without origin of a sound and island, will lead to a great transformation of the landscape and the ecosystem.