COVID-19 is not only causing economic and social difficulties but also giving a warning message to the humankind ‘Be humble to the nature and decrease your desires.’ The response to the rise of the sea level, caused by the increase of the greenhouse gas emission and the melting of the glaciers, is drawing more and more attention as a major international issue. How much do we know about the behavior of greenhouse gas and glaciers? Scientists have bored holes into the glaciers to see the internal conditions and obtain the past records about climate change. The glaciers are like time capsules that contain the records of climate change over time, which are necessary to diagnose the earth and predict the future of our planet.

The analysis of the oxygen (O) and hydrogen (H) in the ice (H₂O) of the glaciers or the measurement of the temperature inside the boreholes gives hint about the past temperature variation. The air of the past captured in the glaciers also provides information regarding the change of the glacier thickness and the concentration of the greenhouse gases in the atmosphere. The Laboratory for Ice Core & Paleoclimate at Seoul National University usually conducts studies by using the glaciers in the Antarctic and Greenland. The research is focused on the Antarctic, which treasures up about 88% of the earth’s glaciers and well preserves the past records of climate change in the relatively clean environment.

One of the research projects is to investigate the change of the concentration of carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O), the representative greenhouse gases, and the causes of the change. The glaciers in the Antarctic and Greenland contain numerous air bubbles, from which the past air is extracted to analyze the components. Glacier samples of a small volume are used to measure the concentration of greenhouse gases and the ratio of isotopes (ratio between heavier and lighter atoms) to investigate how greenhouse gases are formed and decomposed. This study requires expensive instruments, including specialized refrigeration facilities, vacuum lines for air extraction, and mass spectrometers for the measurement of isotopes, and the travel to the Antarctic to directly observe and measure the glacier conditions.

International joint research is also needed, because the analytical data obtained from the Antarctic and Greenland are used to understand the relationships among the elements of climate change in the entire Antarctic or in the global scale. The international joint research team published the results in Science in last June. The team recovered the past temperature change in the surface layer of the Antarctic by using the data about the borehole temperature in the Antarctic glaciers and the age of the glacial ice and the air captured in it.

We are now living in the interglacial epoch.* A recent study conducted on the temperature of the glacial epoch showed that the temperature in the west Antarctic was about 10℃ lower and the temperature drop in the east Antarctic (4-7℃) was about half of the previously known temperature drop (about 9℃). The difference of the temperature change between the east and the west was assumed to be the result of the difference of the elevation of the glacial surface. In the recent glacial epoch, the glacial surface was elevated in the west Antarctic, while it was rather descended in the east. These results will increase our understanding of the glacial behavior and the rise of the sea level and be applied to the development and verification of climate models, contributing to the increase of the accuracy of the prediction of the future climate.

One of the areas of climate change that requires research most urgently is cryosphere consisting of the ice of the earth. The cryosphere includes the glacier, formed by the snow compacted on the ground; the permafrost, the soil that remains frozen for two or more years continuously; the sea ice, formed by the freezing of the sea water; and the snow, distributed according to the season. The cryosphere responds to the global warming most sensitively. Cryospheric science is a research area that is essential to the scientific understanding of the concentration of greenhouse gases in the atmosphere, the ocean circulation, the variation of the sea level, and the changes of the terrestrial and marine ecosystems.

Cryospheric Science Education and Research Center was newly established in the Siheung Campus on May 31 so that Seoul National University may efficiently play the role of an international leader in Cryospheric Science, foster the human resources for the research, and provide education to the citizens. We are looking forward to seeing the day when Korean scientists and citizens take the lead in addressing the global issues.