Eiichi Tajika / Professor / Division of Transdisciplinary Sciences
Department of Complexity Science and Engineering / / Earth and planetary system science

Career Summary
1987: BSc (University of Tokyo)
1992: DSc (University of Tokyo)
1992-1993: Postdoctoral Fellow (University of Tokyo)
1993-2002: Research Associate (University of Tokyo)
2002-2010: Associate Professor (University of Tokyo)
2010: Professor (University of Tokyo)
Educational Activities
Graduate school: Earth and planetary environmental evolution
Faculty of Science: Basic examination of Earth and planetary environmental science I, Basic examination of Earth and planetary environmental science II, Earth system evolution, Earth history, Geochemical cycles
Research Activities
My research interests are the evolution of the Earth and the terrestrial planets (especially their climate evolution) and stability and variability of the climate systems. I have investigated the roles of mantle cooling and global geochemical cycles in the Earth and planetary evolution by using numerical models. My recent research topics are reconstructions of climate change and geochemical cycles during the Earth's history and at several geological boundary events, and also the Snowball Earth events during the Proterozoic.
I am also interested in the climate systems of earth-like planets around the extra-solar planetary systems. I have studied the stability and variability of the climate systems of exo-planets with very different conditions to those of the Earth.
1) Sekine, Y., Tajika, E., Ohkouchi, N., Ogawa, N. O., Goto, K., Tada, R., Yamamoto, S., and Kirschvink, J. L. (2010) Anomalous negative excursion of carbon isotope in organic carbon after the last Paleoproterozoic glaciation in North America, Geochemistry, Geophysics, Geosystems (in press).
2) Misumi, K., Yamanaka, Y., and Tajika, E. (2009) Numerical simulation of atmospheric and oceanic biogeochemical cycles to an episodic CO2 release event: implications for the cause of mid-Cretaceous Ocean Anoxic Event-1a, Earth Planet. Sci. Lett. 286, 316-323.
3) Tajika, E. (2008) Theoretical constraints on early Earth's environment, Viva Origino, 36, 55-60.
4) Tajika, E. (2008) Snowball planets as a possible type of water-rich terrestrial planets in the extrasolar planetary system, Astrophysical Journal Letters 680, L53-L56.
Other Activities
Member of the Japan Geoscience Union (JpGU), The Japanese Society for Planetary Sciences, The Seismological Society of Japan, The Meteorological Society of Japan, American Geophysical Union (AGU), and Geological Society of America (GSA)
Future Plan
We aim to understand the characteristic behaviors and evolution of climate systems of the Earth and other planets, as well as those of planets in extra-solar planetary systems. Investigating snowball Earth events (global glaciations) would be a key to understanding the behaviors of both the Earth and the earth-like ocean planets around the extra-solar planetary systems.
Messages to Students
I hope you will join us in revealing the complex behaviors of the Earth system and other planetary systems through use of interdisciplinary knowledge and approaches.