Interview

Find a solution to the climate crisis in the old future: glaciers

Jinho Ahn, Professor at the School of Earth and Environmental Sciences

Professor Ahn, undeterred by the geologically inhospitable conditions in South Korea, a barren land for glacier studies, has developed the country's sole glacier GHG(Greenhouse Gases) concentration measurement instrument to prepare a domestic environment for glacier research. He measures the concentration of GHGs in the atmosphere from glacial samples, explores paleoclimatic conditions, and establishes climate models to predict the future through the past.

Researchers who arrived at Jang Bogo Station, the second Antarctic base of South Korea in 2014, encountered a landscape surrounded by ice and a temperature of -35.8℃, with endlessly unfolding glaciers. Even the distant mountain peaks appeared tiny. Professor Jinho Ahn, who had analyzed glaciers in the laboratory for 10 years, remembers that day when he first set foot in Antarctica as a new starting point in his life.
“I began investigating past greenhouse gases (GHGs) contained in glaciers during my doctoral program after previously studying geology until receiving my master’s degree. Upon arriving in Antarctica, the overwhelming natural environment was awe-inspiring. Simultaneously, however, I realized that humans are magnificent as well. Are they not developing a way of looking into the future through a piece of glacier that contains a long history?”
Professor Ahn, undeterred by the geologically inhospitable conditions in South Korea, a barren land for glacier studies, has developed the country's sole glacier GHG concentration measurement instrument to prepare a domestic environment for glacier research. He is currently working as a participating researcher for Carbon Neutrality Cluster at the Institute for Future Strategy at SNU.

GHGs will not disappear even after 10,000 years

Professor Ahn measures the concentration of GHGs in the atmosphere from glacial samples, explores paleoclimatic conditions, and establishes climate models to predict the future through the past. “GHGs, are rising as if to fill the entire atmosphere of Earth. But what were GHGs like in the past?” he asks. The solution is hidden in glaciers that regularly contain the GHGs occurring one million years ago. Resolving the problem of GHGs will determine the safety of Earth and humanity. Professor Ahn feels a heavy responsibility as a scientist.
“Once emitted, GHGs do not immediately disappear. That is a key problem. Even if carbon emissions are reduced to ‘zero,’ the concentration of existing GHGs does not drop immediately. This is because the length of time that previously emitted carbon stays in the air varies from several hundred to several thousand years. Studies have shown that 10% to 20% of the carbon dioxide emitted since the Industrial Revolution will remain even after 10,000 years. Even if global carbon emissions cease at this point, glaciers that have already begun to thaw will continue to melt, and sea levels will rise. What we need to do is reduce carbon emissions to mitigate various climate catastrophes. Compared to most developed countries, including those in Europe, South Korea is lagging considerably behind.”

Glaciers reveal the future of Earth

In 2015, the United Nations Framework Convention on Climate Change Conference of the Parties adopted the Paris Agreement to cap the rise in global average temperatures in 2100 to 2℃, furthermore, to 1.5℃ above the pre-industrial levels, thereby calling the world to focus on responding to the climate crisis. Professor Ahn, who participated as the main author of the Intergovernmental Panel on Climate Change report, published in 2021, felt impatient. He knew that South Korea's monitoring system for measuring GHGs remained at a rudimentary level. While leading the Glacier/Paleoclimate Research Laboratory, he introduced an isotope analysis that can identify where GHGs have originated to measure the concentration of GHGs, which can be used to develop accurate climate models, and he has been entirely devoted to training a highly qualified workforce to brace for the climate crisis.
“The reason we need to reconstruct past climates at this point is to develop accurate climate models. GHGs stay long in the atmosphere. Methane, nitrous oxide, and carbon dioxide remain for approximately 10, 120, and thousands of years, respectively. Thus, a comprehension of these GHGs requires super-long-term data. Since the 1980s, this need has motivated scientists to pioneer studies on GHGs utilizing glaciers. These studies related to various topics, including how GHGs and climate have been correlated, and how sea levels have shifted when glaciers melted. In this respect, an investigation into the ‘cryosphere (氷圈),’ which is covered by glaciers and snow, is of paramount importance. This region enables scientists to predict future climates, in addition to preserving the history of climate change.”

A successful future requires prediction and preparation

Melting glaciers may symbolize global warming. However, what concerns scientists most is irreversibly abrupt climate change rather than a global temperature rise by 1 to 2℃. The Climate Clock warns that if the current carbon emission trend continues, humans will not be able to maintain the same daily routines in seven years. Professor Ahn holds the firm belief that tracing the message, of which the climate of the distant past informs the humankind in the present and future provides invaluable data that allow us to predict the future, which urges him to continue research on GHGs through glaciers.
“There were time periods in the distant past when the temperatures were similar to or higher than those at present. GHGs had suddenly exploded during some periods. These events amount to a kind of natural experiment on climate change. A sophisticated investigation into these data can forecast the future when Earth’s temperatures might rise by 3℃ higher than those at present. If we could discover climates and environmental changes in the past, we would be able to predict environmental changes in biological and ecological aspects.”
As nearly all scientists around the globe predict, it is close to a fait accompli that the climate crisis and climate disasters will become more detrimental in the future. However, Professor Ahn emphasized that our actions at present will determine whether the sea level will rise by 1m by 2100, or by 5m or 15m by 2300.
“I am currently teaching a liberal arts course on climate crisis at the university. This course enables me to explore how I can view the climate crisis from an economic, humanities, or sociological viewpoint, in addition to a perspective from my research field. The reason why all sectors are engaged in contemplating the climate crisis is that this issue is closely related to our very lives.”

In GHG research projects utilizing GHG forecasting models constructed by self-developed technology, oceans, atmosphere, glaciers, and frozen soils are all crucial because they are all interconnected. Professor Ahn, who has been delving into GHGs with a focus on glaciers for over 20 years, is laying the groundwork for accurately predicting the behavior of GHGs through the measurement of GHG isotopes. Furthermore, he hopes that SNU will take the lead in research on the cryosphere, which is gaining attention as a key clue in comprehending the climate crisis.
“Our technology is leading the world in extracting past air from glaciers and measuring the GHG concentrations. The problem is that measurement technology for GHG isotopes is still in its infancy. To accurately understand GHGs, the measurement of isotopes as well as GHG concentrations is important. Thus, South Korea should develop its original technologies, and train a top-quality workforce who can handle the equipment. I will continue to develop GHG behavior models to prepare for future climate environment changes at SNU with students.”

“There were time periods in the distant past when the temperatures were similar to or higher than those at present. GHGs had suddenly exploded during some periods. These events amount to a kind of natural experiment on climate change. A sophisticated investigation into these data can forecast the future when Earth’s temperatures might rise by 3℃ higher than those at present. If we could discover climates and environmental changes in the past, we would be able to predict environmental changes in biological and ecological aspects.”