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A notable increase in research related to geospatial vulnerability assessment of urban floods is observed, primarily driven by the advances in exponential technologies and increasing frequency and severity of such events. Several studies have been attempted in Indian contexts for local-level risk mitigation and preparedness and informed decision-making with a limited scope due to unavailability of granular data at various levels as required. In response to this gap, current study examines the potential of top-down and bottom-up geospatial vulnerability assessment approaches for urban floods in Patna City of Bihar state, India. A qualitative articulation is used to identify and characterise a set of critical indicators and attributes relevant to the local vulnerability assessment of urban floods specific to the study area. Principal Component Analysis (PCA) is applied for dimension reduction and assigning weights to indicators, and Composite Vulnerability Indices (CVIs) at Ward and Household (HH) levels are developed using multicriteria decision analysis. The results show over a fifty percent variation in the vulnerability profiles of households using ward-level (top-down) and HH-level (bottom-up) approaches. Moreover, a narrower range in the z-score of HH-level CVI (−1.26 to 2.60) over ward-level CVI (−3.95 to 2.49) from sensitivity analysis indicates the robustness of the former over the latter. The findings reveal a potential risk of maladaptation when employing a ward-level approach to vulnerability assessment as a policy instrument. The study also analytically validates the significance of localising indicators in regional and global frameworks for achieving efficient decision-making toward sustainability targets. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • National targets for embedded GHG emissions are calculated from the climate goal of the Paris Agreement. • Four explorative consumption scenarios for 2050 are derived based on a large survey of individuals in Denmark. • Reductions in GHG emission intensities of technologies required to meet national emission targets are estimated. • These estimates are compared to historic time series of emission intensities and future scenarios for ten selected technologies. • Results strongly suggest that both changes in "business as usual" and "consumption as usual" are needed. Abstract The COP21 summit in Paris led to a policy commitment of limiting the global temperature increase to 1.5–2.0 °C and this can be translated to a global annual greenhouse gas (GHG) emission budget that is shrinking rapidly throughout the 21st century. Here, we estimate the reductions in GHG emission intensities of technologies that will be required for the embedded GHG emissions of a developed nation to stay within its fair share of a global emission budget in the year 2050. The estimates are made for different conceivable developments in consumption patterns in the case of Denmark, based on a large survey of current consumption patterns. To evaluate whether the required emission intensity reductions are likely to be met, they are compared to historic time series of emission intensities and to projections for 2050, based on policies currently in place, for ten technologies that have a high contribution to current GHG emissions. We estimate that emission intensities must be reduced by factors of 2–12 and 5–14, depending on the development in consumption, for the 2.0 and 1.5 °C climate goals, respectively. Of the ten selected technologies, only electricity supply is projected to, partially, meet the most strict reduction target, applying to a scenario where all inhabitants in 2050 consume as the most consuming inhabitants today. The results indicate that both a change in "consumption as usual" and in "business as usual" is needed for developed nations to meet equitable climate targets. This has implications for national and international policies targeting GHG emission intensities and may require a new orientation of policies to consider the societal structures around consumption. [ABSTRACT FROM AUTHOR]

In the construction sector, LCAs typically apply an approach based on fixed or partially fixed building lifespans/service lives/reference study period. The temporal scopes applied in building LCAs are hence typically not reflecting that the timeframes buildings can provide the service they are intended to provide, are (highly) dependent on numerous factors e.g.: building location, materials used to construct the building, energy supply and the use of the building. Inaccurate estimation of the temporal scope of a building LCA will lead to incorrect quantification of the environmental impacts of buildings. Incorrect quantification of the environmental performance of buildings may, in the worst case, derange/decelerate the development within the building sector towards more sustainable buildings. In this paper, a data set consisting of 20999 Danish buildings, demolished between 2009 and 2015, is analyzed. A multiple linear regression model is derived and used to quantify the temporal scope (often referred to as the reference study period) of building LCAs in an attempt to improve the accuracy of sustainability assessment of buildings, taking several influencing factors into account. The results obtained from the derived model are subsequently compared with several fixed/partially fixed building lifespan/service life/reference study period quantification approaches The regression model proved to estimate the lifespan with lower errors (compared to observed values) than the prevailing approach relying on a single fixed value for all building locations, uses and building materials. The application of model based site, use, and/or material specific etc. temporal scope quantification in LCA is new and provides a mean to reduce the uncertainty of LCA results; however, the approach needs to be formalized. [ABSTRACT FROM AUTHOR]

Our paper presents a novel approach for absolute sustainability assessment of a building's environmental performance. It is demonstrated how the absolute sustainable share of the earth carrying capacity of a specific building type can be estimated using carrying capacity based normalization factors. A building is considered absolute sustainable if its annual environmental burden is less than its share of the earth environmental carrying capacity. Two case buildings – a standard house and an upcycled single-family house located in Denmark – were assessed according to this approach and both were found to exceed the target values of three (almost four) of the eleven impact categories included in the study. The worst-case excess was for the case building, representing prevalent Danish building practices, which utilized 1563% of the Climate Change carrying capacity. Four paths to reach absolute sustainability for the standard house were proposed focusing on three measures: minimizing environmental impacts from building construction, minimizing impacts from energy consumption during use phase, and reducing the living area per person. In an intermediate path, absolute sustainability can be obtained by reducing the impacts from construction by 89%, use phase energy consumption by 80%, and the living area by 60%. [ABSTRACT FROM AUTHOR]

Residential building insulation is regarded as an easy solution for environmentally friendly building design. This assumption is based on the perception that the amount of thermal energy used to create insulation in most cases is much smaller than the amount of thermal energythat is needed for space heating without insulation over the lifespan of a building. When the energy sources for insulation production are similar to the energy mix that supplies heat, this logic is valid to very high level of insulation. However, in Denmark, as well as many other countries this assumption is becoming increasingly incorrect. Given the generally long service life of buildings, the significance of future energy mixes, which are expected/intended to have a smaller environmental impact, can be great. In this paper, a reference house is used to assess the life cycle environmental impacts of mineral wool insulation in a Danish single-family detached home. This single-family house, is based on averages of current Danish construction practices with building heat losses estimated using Be10. To simulate a changing district heating grid mix, heat supply fuel sources are modeled according to Danish energy mix reports of fuel mix since 1972. Both the dynamic impact potentials saved by using insulation and the impacts induced from insulation's production are utilized to create an overall dynamic energy inventory for the lifecycle assessment. Our study shows that the use of such a dynamic energy inventory is necessary for increasing the validity of optimization assessment, and our study further shows that it is likely that current Danish regulation will not promote optimum levels of insulation in the near future. [ABSTRACT FROM AUTHOR]