Global warming caused by the emissions of greenhouse gases (GHG) including CO2 derived from fossil resources is already becoming obvious in various parts in the world. Not only global warming but also enlargement of various environmental loads and resource consumption due to human activities have been warried strongly. In recent years, climaterelated risks of unusual weather, natural disasters, the failure to the implementation of mitigation and adaptation for climate change occupy top places for the concern in the world.

It is considered that there is an upper limit for the cumulative GHG emissions acceptable in the future in order to keep the global average temperature increase well below 2℃ comparing with the pre-industrial levels. If this happens, fossil resources exceeding the upper limit would become stranded assets that are unavailable even if they are developed. As a response to these risks, a high possibility will be anticipated to further advance decarbonization escaping from fossil resources and the transition to a clean energy system. In addition, due to the geopolitical risks, it is highly uncertain to forcast crude oil prices for mid- and long-term, but investment in clean energy by a private sector is expected to steadily advance in the future.

Within this trend, countries and regions are working together and exploring the international cooperation with the United Nations' Sustainable Development Goals(SDGs) and the Paris agreement. And for the development of their coutries, they are working on establishing a stable and economical energy system and conservation, sustainable management and utilization of the environment. Moreover, each country activates investment in technologies for solving social problems, and promotes R&D and its social implementation in combination with changing regulations and rules.

These social changes also affect trends in R&D and advances in; 1) expansion of renewable energy utilization, 2) optimal control of electric power network, 3) storage, transportation and utilization of electric power and heat derived from renewable energy, 4) observation and prediction on all scales of the global environment, 5) prediction and evaluation of global warming effect, 6) analysis for dynamics of useful resources and pollutants, and its sustainable utilization. Various R&Ds are promoted in response to society's demands.

On the other hand, there is another trend affecting R&D from the technical side as well. The volume of date obtained through the Internet of Things (IoT) and various sensor networks is massively expanding. Some opportunities to produce new knowledge and information by using AI and other statistical techniques are emerging.

The highlights of R&D trends in the environment and energy fields is shown below.

TheThe situation of R&D in Japan is shown below. <Energy field>

• The fields of thermal power and nuclear power in Japan maintain international competitiveness traditionally in fundamental research, application and development. Now they are at a crossroads as to how to proceed due to rapid social change in the domestic and overseas.
• The field of renewable energy is actively expanded globally. Although Japan has accumulated R&D for this technology, it is difficult to see a powerful movement that the result of basic research progresses to application and development rsearch, leading to social implementation further. This situation is often caused by social and environmental restrictions such as policy, regulation, geographical conditions.
• The field of energy management is showing excitement. R&D for stabilization of the electric power system and for the service utilizing a new technology become active.
• The chemical field is also important. Active discussions and efforts can be seen in industry, academia and government for basic research, application and development from the viewpoint of fossil fuel conversion and CO2 emission reduction.

<Environment field>

• In the field of environment observation, many R&Ds in the field of water ane carried out at various scales including high precision of rainfall observation, prediction of outflow of small and medium rivers, global water circulation, and climate change adaptation measures. Japan also provides an important contribution internationally in ocean observation. However, it is not relatively so active in Japan to raise a research project focusing on the integration and analysis of large amounts of data, or that designing a large-scale field reserch project.
• In the field of climate change adaptation, the development of the earth system model (ESM) and utilization of the result are progressing with different field collaboration under the policy support. But efforts to evaluate society and ecosystems together and to study their governance are behind compared to other countries.
• In the field of water treatment, removal and purification of pollutants, R&D is progressing individually. Top-level research has been developed for automobile exhaust after-treatment technology.
• In the field of environmental analysis, LCA and resource utilization, some R&Ds have been actively conducted. There is not so many systemic research project such as comprehensive environmental assessment, database construction and system development.

In order to respond societal needs, it is necessary to show a major direction of R&D from a mid- to long-term perspective and to promote R&D considering the overall balance. To achieve this, the policy leadership will be also more important.

There are five keywords for future direction of R&D in the field of environment and energy. They are "Zero emissions", "Adaptation", "Circular", "Smart", and "Safety". 'Sustainability' and 'Inclusiveness' are setted as core values to build and develop a sustainable society. And it is necessary to promote many R&Ds integrally while showing these fi ve keywords as a major direction. This concept also basically matches the direction that the international community is aiming for, and efforts in Japan are required to be aware of international cooperation.

A summary of each keyword and its relevance to R&D are shown below.

• Zero emission ... "Zero emission" refers to achieving net zero carbon emission by balancing an amount of CO2 released in the atmosphere due to human activity and absorbed technically. Although the drastic reduction of CO2 emissions is the most important issue, there are some approaches to recover, store or utilize atmospheric CO2. Wide range of R&Ds are required including the possibility of so-called 'negative emissions'.
• Adaptation ... It is important increasingly more and more now. The impact of climate change becomes obvious and society may suffer serious damage unless adaptation measures are taken. On the other hand, adaptation measures will lead to change in society and it is not enough to merely disclose scientific knowledge or introduce some kinds of technology or system. It is important to advance it together with society.
• Circular ... This refers to the formation of a recycling-oriented society. Recently the problem of marine plastic wastes is being taken up quite seriously in the international community. Science and technology must respond to such social demands.
• Smart ... It is a big issue how to utilize data effectively within the rise of AI / IoT trend as described symbolically in Society 5.0.
• Safety ... It refers to safety in various ways. Japanese society is in the threat of natural disasters due to its geographical characteristics. It will be more important to consider the impact of climate change in the future and to strengthen the responding to these various kinds of disasters. As Japan has poor resources and it must rely on importing the most of energy resources from overseas, energy security is the fundamental problem related to the nation's survival base.