Project for international cooperation on the analysis and assessment of technologies for climate change mitigation (ALPS II; FY2012-FY2016)
ALPS Project（ALternative Pathways toward Sustainable development and climate stabilization）
Research Works
In this project, we conducted the following tasks (1)-(6). (1) Climate risk management based on the quantitative analysis carried out otherwhere within this project, while pointing out various types of uncertainties related to climate change. In particular, we conducted a study using a questionnaire survey to experts on this subject. Besides, it presents our analysis of long-term emissions pathways for the long-term targets of the Paris Agreement (2ºC target, 1.5ºC target), and our survey on international discussions on limitation and capability of BECCS. Last, it also includes an assessment of the economic impact and effectiveness of adaptation measures, based on a review of past literature on assessments of climate change impacts and adaptation measures. (2) CO2 emissions factors on the global level and for major countries in order to search for green growth opportunities while properly recognizing its limits. Furthermore, we conducted an evaluation of the Japan-US energy productivity gap, and analyzed policy issues for EU electricity market liberalization and climate policy. (3) Analysis of long-term mitigation scenarios. It includes our model analysis of the Shared Socio-economic Pathways (SSPs); we defined our own SSPs considering international activities on SSPs build-up and analyses. It also comprises our evaluation of co-benefits for air pollution (PM2.5) emissions and reduction. (4) Analysis of medium term mitigation scenarios, namely our analysis and assessment of "Nationally Determined Contributions" (NDCs) of the Paris Agreement as 2030 emissions reduction targets. (5) Technical measures to pursue green growth concretely, such as hydrogen systems, off-grid electricity systems, and potential initiatives in the residential and transportation sectors. (6) The latest overseas climate policies and IPCC activities as well as the various model analysis that were conducted within international model comparison projects, and related upgrades of our model to meet the requirement from the international model comparison projects. Key points of tasks (1) to (6) are described in the following paragraph.
Today, there is almost no room left for any doubt regarding the argument that climate change and global warming have an anthropogenic origin. Moreover, in order to ensure climate stabilization, it is necessary to reduce CO2 emission to nearly zero. However there is great uncertainty regarding climate sensitivity and climate-induced damage. There is also great uncertainty regarding the cost of climate change mitigation. The primary factor for the increase in mitigation costs resides in the uncertainty around future socioeconomic pathways (which will be evaluated in detail in (3)). We can also point out significant disparities across countries in terms of the marginal abatement costs to achieve the NDCs of the Paris Agreement. Moreover, if we take into account national constraints such as the nuclear stance, the necessity to conciliate mitigation goals with energy security and other national policies, and other constraints from each country's political system, the total mitigation cost is probably much higher than the mitigation cost assessed with cost minimization methods (which will be concretely evaluated in (4)). In addition, the political stability of the climate change framework is also an important issue. In such a context, and taking into account various risk factors, there is great need for good decision making in climate change response. On the other hand, political decisions such as the long terms 2ºC target, 1.5ºC targets must also be taken into account.
An analysis of long-term emissions pathways for long-term targets (2ºC target, 1.5ºC target) of the Paris Agreement was conducted. It also introduces international discussions on the possibilities of BECCS and Direct Air Capture (DAC) to play important roles, as they may become necessary given the stringency of these targets.
Moreover, an economic model was newly built to analyze the economic impact and effectiveness of adaptation measures, based on a review of past literature on assessments of climate change impacts and adaptation measures.
Furthermore, the value of the strategy of holding geoengineering (the Solar Radiation Management (SRM)) as an option is quantitatively estimated, and its role in risk management strategies is explored. Besides, we point out the necessity to harmonize risk management strategies and innovation strategies since technology innovation will be necessary to achieve large emissions cuts. Last, a questionnaire survey on climate risk management was submitted to experts; the results of which showed that there are very different views between experts regarding this issue. As climate change is a very wide issue, related uncertainties are great which is why disparities between experts' views are great as well. This work should be furthered by both deepening the research on relevant areas and strengthening the communication on particular points.
We examined limits and potential of green growth using quantitative data as far as possible. Recent trends show that while world GDP keeps growing, world CO2 emissions do not follow the same trend or may even be doing the reverse. In particular in some parts of Europe, GDP is growing but CO2 emissions are decreasing. We hereby seek the cause of this phenomenon. For one thing, the impact of China' steel sector on world emissions is very high. Between 2010 and 2013, the growth of this sector was particularly important, which had a strong impact on world emissions. The shale gas revolution in the US also had an impact. Regarding the case of Europe, the decoupling of GDP and CO2 emissions (or energy consumption) roots mainly in changes of industrial structure; on the other hand, measuring consumption-based emissions show that there was no significant decrease.
Moreover, it examines the opportunities for green growth - while properly recognizing its limits - through the evaluation of the Japan-US energy productivity gap. Analyses were conducted on iron and steel sector and the productivity gap was estimated for each process of manufacturing; in particular, we drafted materials useful to investigate related green growth potential and limits.
Besides, we conducted literature review on the current situation of renewable integration in Europe and Japan and related issues. In particular, we documented the European case as a past example of combined issues coming from simultaneous implementation of electricity market liberalization and climate change mitigation policy. Furthermore, we analyzed and assessed international policies aiming at limiting the financing of coal-fueled generation, as well as the issues and trends related to the international fund for technology transfer.
We carried out a comprehensive analysis of global warming measures and policies using integrated assessment model and global energy-economic model. In accordance with the marker SSPs scenarios, we consider five socio-economic scenarios to 2100 (including population, per-capita GDP, and fossil fuel prices) and assess climate change strategies with world energy and climate model DNE21+. Besides, we analyze the impact on macroeconomy with global energy-economic model DEARS. We also analyzed the relationship between land use and water resource for the same socioeconomic scenarios and emissions constraints using a water resource assessment model for land use and agriculture.
An evaluation of co-benefits for air pollution (PM2.5) emissions and reduction was conducted. The effects of emissions of SO2, NO2 on PM2.5 concentration, as well as emissions reduction measures, were introduced in DNE21+, allowing to conduct an integrated analysis of climate change mitigation and PM2.5 emissions reduction and to quantify the co-benefit between climate change mitigation and PM2.5 reduction. However, the co-benefits differ significantly among regions, as they are assessed to be modest in Japan, but relatively high in India and the US. Besides, the quantified assessment showed that if the benefit from PM2.5 emissions reduction is higher than the benefit from climate change mitigation, it would then be more cost-effective to favor measures focusing on PM2.5 emissions reduction.
We analysed NDCs (2030 emissions targets) contained in the Paris Agreement. Within the framework of the Paris Agreement, an international review of NDCs is needed. In this research, an assessment of each country's Intended Nationally Determined Contribution (INDC) was conducted based on a selection of various indicators relevant to assess the emissions reduction effort. In addition, a comparison between several models was conducted. We also evaluated the impact of different forecasts of fossil fuels prices on marginal abatement costs and thus on achieving the targets. However, for each country, as we can see in their presentation of concrete mitigation measures, other factors come into play, such as constraints related to technological development, energy security and other national policies, and other constraints from each country's political system. We assessed how much the cost of achieving the target changes when taking all of those constraints into account, using model analysis. As a result, considering all types of constraint, the mitigation costs are likely to increase significantly.
We investigated the specific technological options and measures that can lead to green growth. After the Fukushima Daiichi nuclear accident, Japanese energy policy focuses particularly on the development and deployment of hydrogen system. Based on a review of trends in this field, an analysis and assessment of hydrogen system are conducted.
Moreover, in some of the regions lacking electricity, we observe a growing use in off-grid renewable systems. In this context, a comparison of economics between off-grid renewable systems and classic grid connection is conducted.
Besides, to encourage green growth, not only the aspect of energy use should be considered: the creation of new services should be examined, while new ways for energy savings and decarbonization are essential as well. While pointing out both the necessity and difficulty to reduce electricity use, the study discusses the possibility and necessity to create integrated new services to move towards Society 5.0 as advocated in the Fifth Science and Technology Policy Plan.
We investigated the latest trends for IPCC and international policies, and the current situation for international inter-modeling comparison projects. Regarding international policies, changes to be expected due to Brexit in the EU and the election of President Trump in the US were investigated as well. Moreover, as the Sixth Assessment Report (AR6) preparation started, international inter-modeling comparison projects are being run in view of contributing to it: the IAMC (Integrated Assessment Modeling Consortium) in which major integrated modeling teams are participating, the EMF30 (Energy Modeling Forum) with two main themes of short-lived climate pollutants and bioenergy that is organized by Stanford University, the ADVANCE project (Advanced Model Development and Validation for the Improved Analysis of Costs and Impacts of Mitigation Policies) working on improvement of models that is funded by the European Commission, the MILES project (Improve Modeling Capacity to Support Low Emission Development Strategies) coordinated by IDDRI, and the CD-Links Project (Linking Climate and Development Policies Leveraging International Networks and Knowledge Sharing) coordinated by IIASA, exploring national and global transformation strategies for climate change and their linkages to a range of sustainable development objectives.
