[A-CG34] Projection and detection of global environmental change

[ACG34-P03] Development of an integrated earth system model, MIROC-INTEG-ES and a scenario analysis of future long-term changes in earth system

*Tokuta Yokohata¹, Yusuke Satoh², Irina Melnikova¹, Tomohiro Hajima³, Kaoru Tachiiri³, Ken'ichi Matsumoto⁴, Tsuguki Kinoshita⁵, Akitomo Yamamoto³, Shintaro Takao¹, Masakazu Yoshimori⁶, Akira Oka⁶, Youichi Kamae⁷, Kazuya Nishina¹, Akihiko Ito¹, Ayako Abe-Ouchi⁶, Fuyuki SAITO³, Kazuyuki Saito³, Tetsuo Sueyoshi³, Hideo Shiogama¹ (1.National Institute for Environmental Studies, 2.Korea Advanced Institute of Science and Technology, 3.Japan Agency for Marine-Earth Science and Technology , 4.Toyo University, 5.Ibaraki University, 6.The University of Tokyo, 7.Tsukuba University)

Keywords:Earth system, Human activity, Climate Change

Toward the realization of the Paris climate target, the movement toward decarbonization is accelerating in the world. For example, Japan aims to reduce greenhouse gas emissions by 46% from 2013 levels by 2030 and to reduce greenhouse gas emissions to zero by 2050 (carbon neutral). Therefore, it is a very important issue to show how a decarbonized society can be realized. On the other hand, the Emissions Gap Report shows that there is a very large gap between the amount of emission reductions required to meet the targets set by the Paris Agreement and the current amount of emission reductions. For this reason, it is extremely important to investigate the possibility of achieving the target temperature once after the temperature target has been exceeded (overshoot scenario) and to investigate the risks if a decarbonized society is not achieved as expected. If a decarbonized society is not realized, long-term climate change could raise very serious problems. Demonstrating the risks of not realizing a decarbonized society also leads to demonstrating the necessity of a decarbonized society.
In order to show 1) a path to achieving a decarbonized society at such a speed as to achieve the temperature target set by the Paris Agreement, 2) a path to achieving the target temperature once the temperature target is exceeded, or 3) the problems that would arise if a decarbonized society is not achieved, it is necessary to consider the complicated behavior of the Earth system, as well as that of Human systems related to society and economy. Since the Earth system influences the Human system in many ways, and at the same time the Human system also influence Earth system, we have been developing an integrated model which considers these interactions. So far, we have developed an integrated land surface model, MIROC-INTEG-LAND (Yokohata et al. 2020, GMD, https://doi.org/10.5194/gmd-13-4713-2020), which can consider physical processes in the land area and carbon cycles in the ecosystem, human water management, crop growth, and land use change. Furthermore, we are developing an integrated earth system model, MIROC-INTEG-ES, which couples water management, crop growth and land use models with the latest earth system model MIROC-ES2L (Hajima et al. 2020, GMD, https://doi.org/10.5194/gmd-13-2197-2020). This presentation first introduces the status of the development of MIROC-INTEG-ES. In addition, we also introduce an analysis of long-term changes in the earth system, assuming a decarbonized society is not realized. The latter is research that evaluates physical and carbon cycle processes in the atmosphere, ocean, and land under a climate scenario beyond 2100 (Extended RCP) and demonstrates the various risks if a decarbonized society is not realized.