Faculty of Science and Technology findings by a group led by Professor Seishin Faculty of Science and Technology have been published in "Geology," the international journal of the Geological Society of America.
Release Date:
Traces of Climate Change on Mars: Ice Time Capsules Preserved in Mid-Latitude Craters
A research group led by Professor Seishin Hasegawa of the Faculty of Natural Sciences at Kochi University ( Faculty of Science and Technology) investigated more than 750 craters in mid-latitudes using high-resolution images (HiRISE, CTX) from NASA probes. By combining ice-formed landforms, crater ages, and climate models, the group elucidated changes in ice accumulation and distribution over the past approximately 600 million years.
As a result, it was found that ice tends to accumulate on the southwestern side of the crater. This was determined to be caused by “cold traps” resulting from reduced solar radiation and shadowing. Furthermore, it was discovered that ice accumulation occurred not just once, but two or three times in the past; the direction of supply and thickness varied in each instance, and these events were influenced by climate changes associated with fluctuations in the tilt of Mars’ rotational axis.
About 640 million years ago, ice covered the planet in a thick layer, but it subsequently diminished, and by the time of the last ice accumulation (about 98 million years ago), its distribution had become limited. This indicates that Mars transitioned from a humid era to a dry and cold one.
These findings provide important insights not only for unraveling the history of Mars’ ice and climate but also for the future use of water resources in exploration missions. The study was published in the international journal *Geology*, published by the Geological Society of America, at 1:00 a.m. on September 3 (Japan Standard Time).
■Paper Information
Title: Long-term and Multi-stage Ice Accumulation in the Martian Mid-Latitudes During the Amazonian
Published in: Geology (Geological Society of America)
Authors: Trishit Ruj, Hanaya Okuda, Goro Komatsu,
Hitoshi Hasegawa, James W. Head, Tomohiro Usui, Shun Mihira, and Makito Kobayashi
This research was conducted with support from the Grants-in-Aid for Scientific Research (JP17H06459, JP23K19081, JP24H01036) and the Japan Society for the Promotion of Science (JSPS) Research Fellowship for Young Scientists (JP20J20413).