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QC 20160205

QC 20131007

Nutrient loads to aquatic recipients can be expected to change due to climate change. In this work, we focus on nitrogen loads to the lake Råcksta Träsk in Stockholm, Sweden as an example of an urban ecosystem. A substance flow model is developed to describe the sources and pathways of nitrogen at present. A feed-back table approach is applied to indicate potential climate change effects on nitrogen source strengths and processes in pathways, using existing regional climate change scenarios. The tentative results indicate that biological, hydrological, meteorological and biogeochemical effects and change in human behavior as response to climate change may lead to altered nitrogen flows through an urban catchment. QC 20160509

QC 20131007

This paper examines the possible existence fan Environmental Kuznets Curve (EKC) relationship between China's carbon dioxide (CO2) emissions per capita (CO2/capita) and GDP per capita (GDP/capita) during the period 1980-2008. The timing of the turning point in China's CO2/capita can be further estimated if an EKC relationship exists. In regression results, a natural logarithm-quadratic relationship was found between CO2/capita and GDP/capita, which supports the EKC hypothesis. However, China's CO2 emissions are still on a growing track until around 2078 in empirical analysis. More importantly, CO2 emissions will not spontaneously decrease if China continues to develop its economy without adopting instruments for mitigating climate change. China's wealth gap and China's role in international trade are discussed as two possible factors to affect EKC hypothesis. Therefore, reduction in domestic income inequality and negotiations to allocate responsibilities between China and developed countries for CO2 emissions associated with China's exports arc suggested as further efforts. QC 20130109. Updated from submitted to published.

Separating household waste into fractions at the place where it was generated is one of the most popular methods of collection household waste in most European countries. In 1994 a producer responsibility ordinance for packaging was introduced in Sweden. This ordinance mandates householders to sort out packaging waste, clean the waste and sort different package materials – paper, plastic, glass and metal in assigned recycling bins. Household’s participation is mandatory but in practice it is rarely controlled and enforced. In our study we have focused our interest on seeing the composition of the “trash bags”, theoretically the rest of the waste after household sorting. The aim of the study was to identify the main fractions of household “trash bags” and the difference in the fraction among 3 different districts in Stockholm, which have practically analogous facilities for separate collection of household waste but rather different socioeconomically characteristics. The chosen districts were located: one in the downtown and two in the suburb districts, one of which has a big multicultural characteristic due to the big amount of emigrants living there. The results of the study show that the biggest fraction from the composition analyses is organic fraction. This fraction is varying from 48% in the multicultural suburban district to 34% in the downtown. These results show the big opportunity for implementation the separate organic waste collection spatially in the suburban areas of Stockholm. The amount of packaging material in the “trash bags” still composes around 28-50%. The composition of the packaging material differs in the 3 districts QC 20120919

QC 20120215

Two CDM projects were compared in terms of their impacts on SD, using the popular AHP method. Two experimental groups of post-graduate students performed the assessment and both found that the HFC23 decomposition project studied was a bigger contributor to SD than the hydropower project, although the details differed. The outcome could have been different if the assessment had been performed by real stakeholders and decision-makers instead of students. Nevertheless, the study confirmed that AHP can be a useful method for decision-making especially in a complex situation relating to SD. However, some weaknesses of the AHP method were identified. These, inter alia, included: (1) the final results depended heavily on the participants in the assessment; (2) only a limited number of alternatives can be considered; and (3) the final results are difficult to use elsewhere. QC 20110816

This paper aims to study the co-benefits of clean development mechanism (CDM) projects, and further to discuss the policy of its implications. It has been found that many energy-related climate change mitigation (CCM) activities, including CDM projects, are able to produce a significant amount of co-benefits, while the policy implications have been limited. Through co-benefits assessment of Chinese CDM projects, it can be concluded that: (1) there are uncertainties relating to co-benefits assessment; (2) co-benefits assessment can be only applied to energy related projects (ERPs) and not to HFC23 decomposition projects; (3) hydropower and wind power projects are the largest contributors to cobenefits. Considering average capacity, projects concerning energy switch from coal to natural gas, coal mine methane recovery and biogas recovery are also important; and (4) the distribution of co-benefits in China are uneven. Through a discussion about policy implications of co-benefits, this paper suggest that co-benefits should neither be involved into current international CCM negotiation, nor used to ensure projects’ contribution to sustainable development. However, co-benefits analysis can indicate synergies or optimised trade-offs between CCM and protecting local environment, which is valuable for decision-making in developing countries, especially for local governments. QC 20110816

The environmental impact of internet is growing, reaching an estimated 1.4% of world greenhouse emissions. This impact is hidden for both users and web developers. Understanding and analyzing the environmental footprint of a website is not an easy task. The impacts are distributed through multiple hardware networks and a global user base, making the individual impacts difficult to allocate. This article presents the development of a functional application for generating automatic life cycle assessments for web sites based on mashing-up information. This application has the aim of making the impact of websites visible, allowing the instant analysis of their carbon footprint using existing analytics data and presenting it in an understandable and transparent way. The development process is presented with detailed information about how the calculations are performed. The results are discussed around two different cases, focusing on the challenges of calculating the server side impact and the possibilities for improvement. QC 20111223

QC 20111005