| 1. |
- Alexander, Peter, et al.
(författare)
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Assessing uncertainties in land cover projections
- 2017
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013. ; 23:2, s. 767-781
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Tidskriftsartikel (refereegranskat)abstract
- Understanding uncertainties in land cover projections is critical to investigating land-based climate mitigation policies, assessing the potential of climate adaptation strategies and quantifying the impacts of land cover change on the climate system. Here, we identify and quantify uncertainties in global and European land cover projections over a diverse range of model types and scenarios, extending the analysis beyond the agro-economic models included in previous comparisons. The results from 75 simulations over 18 models are analysed and show a large range in land cover area projections, with the highest variability occurring in future cropland areas. We demonstrate systematic differences in land cover areas associated with the characteristics of the modelling approach, which is at least as great as the differences attributed to the scenario variations. The results lead us to conclude that a higher degree of uncertainty exists in land use projections than currently included in climate or earth system projections. To account for land use uncertainty, it is recommended to use a diverse set of models and approaches when assessing the potential impacts of land cover change on future climate. Additionally, further work is needed to better understand the assumptions driving land use model results and reveal the causes of uncertainty in more depth, to help reduce model uncertainty and improve the projections of land cover.
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| 2. |
- Leclere, David, et al.
(författare)
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Bending the curve of terrestrial biodiversity needs an integrated strategy
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 585:7826, s. 551-556
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Tidskriftsartikel (refereegranskat)abstract
- Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it provides(1,2). Ambitious targets have been proposed, such as reversing the declining trends in biodiversity(3); however, just feeding the growing human population will make this a challenge(4). Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity(5). We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy. To promote the recovery of the currently declining global trends in terrestrial biodiversity, increases in both the extent of land under conservation management and the sustainability of the global food system from farm to fork are required.
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| 3. |
- Mittal, Shivika, 1986, et al.
(författare)
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An assessment of near-to-mid-term economic impacts and energy transitions under "2°C" and "1.5°C" scenarios for India
- 2018
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Ingår i: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- The goal of limiting global temperature rise to "well below" 2°C has been reaffirmed in the Paris Agreement on climate change at the 21st Conference of the Parties (COP21). Almost all countries submitted their decarbonization targets in their Intended Nationally Determined Contributions (INDC) to the United Nations Framework Convention on Climate Change (UNFCCC) and India did as well. India's nationally determined contribution (NDC) aims to reduce greenhouse gas (GHG) emissions intensity of national GDP in 2030 by 33-35% compared to 2005. This paper analyzes how India's NDC commitments compare with emission trajectories consistent with well below 2°C and 1.5°C global temperature stabilization goals. A top-down computable general equilibrium model is used for the analysis. Our analysis shows that there are significant emission gaps between NDC and global climate stabilization targets in 2030. The energy system requires significant changes, mostly relying on renewable energy and carbon capture and storage (CCS) technology. The mitigation costs would increase if India delays its abatement efforts and is locked into NDC pathways till 2030. India's GHG emissions would peak 10 years earlier under 1.5°C global temperature stabilization compared to the 2°C goal. The results imply that India would need financial and technological support from developed countries to achieve emissions reductions aligned with the global long-term goal.
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| 4. |
- Mittal, Shivika, 1986, et al.
(författare)
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Key factors influencing the global passenger transport dynamics using the AIM/transport model
- 2017
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Ingår i: Transportation Research Part D: Transport and Environment. - : Elsevier BV. - 1361-9209. ; 55, s. 373-388
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Tidskriftsartikel (refereegranskat)abstract
- A bottom-up passenger transport model named AIM (Asia-pacific Integrated Model)/Transport model is developed by incorporating behavioral parameters and transportation technological details. This model is based on discrete based choice modelling covering 17 global regions soft-linked with the AIM/CGE (Computable General Equilibrium) model. In this paper, the model is used to assess the impact of various factors like travel time, energy efficiency improvement, load factor, mode preference along with environmental awareness factors on transport demand, energy and emissions. The modelling assessment results show that travel speed and land-use patterns have significant impact on the travel demand. High occupancy rate and shift towards the mass-transit system result in energy and emissions reduction. Implementation of carbon tax aligned with the two-degree target results in a 22% cumulative emission reduction from 2005 to 2100 relative to the baseline case. However, the reduction potential can be increased to 42% by combining behavioral and technology related mitigation options like mass-transit system speed improvement, transit oriented development, efficiency improvement, preference towards eco-friendly technologies and high vehicle occupancy.
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| 5. |
- Prestele, Reinhard, et al.
(författare)
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Hotspots of uncertainty in land-use and land-cover change projections : a global-scale model comparison
- 2016
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 22:12, s. 3967-3983
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Tidskriftsartikel (refereegranskat)abstract
- Model-based global projections of future land-use and land-cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global-scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.
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| 6. |
- Rosa, Isabel M. D., et al.
(författare)
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Multiscale scenarios for nature futures
- 2017
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Ingår i: Nature Ecology & Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 1:10, s. 1416-1419
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Targets for human development are increasingly connected with targets for nature, however, existing scenarios do not explicitly address this relationship. Here, we outline a strategy to generate scenarios centred on our relationship with nature to inform decision-making at multiple scales.
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| 7. |
- Shukla, Priyadarshi Ramprasad, et al.
(författare)
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India INDC assessment: Emission gap between pledged target and 2 °C target
- 2017
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Ingår i: Post-2020 Climate Action: Global and Asian Perspectives. - Singapore : Springer Singapore. ; , s. 113-124
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- India has pledged to reduce the carbon intensity of GDP by 33-35% in the year 2030 compared to 2005 level in its Intended Nationally-Determined Contributions (INDC). The goal of limiting the global average temperature rise well below 2 °C was reaffirmed in the Paris Agreement adopted under UNFCCC. This chapter assesses three scenarios for India spanning till 2030. First, the reference scenario assumes continuation of the ongoing policies along the conventional path. Second, INDC scenario assumes the successful implementation of INDC decarbonization target. Two-degree (2 °C) scenario assumes an emission constraint aligned with the global of 2 °C stabilization target. The modelling assessment is carried out using a top-down computable general equilibrium AIM/CGE (Asia-Pacific Integrated Model/Computable General Equilibrium) model. The results show that even after full implementation of the INDCs, the emissions would still be 25 billion tonnes of CO2 equivalent higher than 2 °C stabilization target over the period 2016-2030. Enhanced actions like penetration of renewable technologies, end-use demand management and improvement in energy efficiency could help to close this emission gap.
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