For over forty years, Chilean glaciologist Hino Cassassa studied the ice masses of Antarctica. At the beginning of his career, he doubted that human activity was causing climate change. Today, Cassassa leads Chile's leading Antarctic research organization—the Chilean Antarctic Institute (INACH)—and he is convinced of the obvious human-induced changes on the continent.
In West Antarctica and on the Antarctic Peninsula, Cassassa has observed rising sea levels, an increase in tourists, and heightened geopolitical tensions. The continent has become one of the territories where the future of climate change is most vividly manifested.
In an interview with Dialogue Earth, Cassassa shared his thoughts on how scientific understanding of Antarctica has evolved, what challenges face the Antarctic Treaty system, and what decisions will determine the continent's future in the coming decades.
When he began working in Antarctica in the early 1980s, he did not expect to see such profound changes. During initial research in 1982, debates still existed about the planet potentially entering a cooling period. For many years, he remained skeptical about the impact of humans on the climate due to a lack of evidence.
However, by the late 1990s, the evidence became overwhelming. As a scientist, he is obliged to follow the scientific method and change his mind when new data emerges. He transitioned from skepticism to complete certainty that global warming is primarily caused by human activity.
One crucial moment was participation in research in the Amundsen Sea, in West Antarctica, jointly with scientists from NASA and the Chilean Navy. There were signs that this region could be a weak point for the continent, and data confirmed ice loss. Simultaneously, very rapid changes were observed on the Antarctic Peninsula, which is one of the regions experiencing the fastest warming.
He emphasized that once a certain temperature is reached, ice begins to melt regardless of any political discussions. Previously, many considered Antarctica a vast freezer where changes occurred on a timescale of thousands of years, whereas what was observed was the opposite: in some areas, changes could have happened in just a few decades.
One of the main questions concerned the role of floating ice shelves. Some scientists argued that their disappearance would not affect the continental ice. Others, including Cassassa himself, believed that these shelves act as a natural brake on the ice behind them. Observations have shown that this brake is real. When a shelf collapses, glaciers accelerate their flow toward the ocean. Events like the collapse of Larsen B ice shelf, where thousands of years of ice disappeared in a matter of weeks, marked a paradigm shift. It also became clear that some regions have already passed tipping points.
The Antarctic Treaty remains a model of international cooperation. The number of participants has grown from 12 original members to 58 participating countries, including 29 consultative members, among which are major powers, and 29 observers. The growing interest from many nations demonstrates that the global community recognizes the immense importance of Antarctica for global climate and the environment.
China, in particular, has significantly increased its presence. It currently has five research bases in Antarctica and plans to build a sixth. China possesses significant scientific experience and resources. This reflects the transformation of the system over the past decades: countries that previously had no presence on the continent are now actively investing in Antarctic research.
The Antarctic Treaty stipulates that the continent must be used 'exclusively for peaceful purposes' and guarantees freedom of scientific inquiry. It was signed in 1959 by 12 countries, some of which have and continue to have overlapping territorial claims. Although there are geopolitical interests, Cassassa believes it is necessary to maintain and strengthen the spirit of scientific cooperation that characterizes the system for more than six decades.
For over ten years, Chile and Argentina have advocated for the creation of a large Marine Protected Area (MPA) in the western part of the Antarctic Peninsula. Scientific support for this initiative is broad, but decisions in the Commission for the Conservation of Antarctic Marine Living Resources are made by consensus, allowing one country to block the approval of a proposal. Some insist on conducting additional scientific research, but they are confident in the necessity of protecting this area. Unfortunately, there are also geopolitical and commercial interests related to krill fishing.
Antarctic tourism is growing annually. Cassassa notes that tourism is not a problem because Chile is one of the main gateways to Antarctica, which brings significant benefits to the region and also serves as a valuable educational tool. However, this growth cannot be infinite and must be carried out in the most sustainable way possible. There is currently a growing consensus on the need to monitor the impact of both tourism and scientific and logistical activities.
If evidence shows that certain activities negatively affect ecosystems, access will need to be restricted or new rules introduced. In terms of environmental responsibility, in collaboration with the European Union and with support from Germany, a pilot plant for green hydrogen production is being developed for the Escudero base, the main station in Antarctica. Currently, the base consumes a lot of diesel fuel and oil for heating and power supply.
Hydrogen, which does not emit greenhouse gases upon combustion, can be considered 'green' if produced entirely using renewable energy sources. This plant will use solar and wind energy and can provide up to two-thirds of the base's annual needs. The project is in the final design stage before environmental assessment, carefully considering the impact on local fauna. This will require very little fresh water, which will be sourced from glacial meltwater lakes. Other countries have already implemented similar projects: Argentina has an operational pilot plant, and China has also launched its own.
The world faces a triple challenge: climate change, loss of biodiversity, and pollution. Efforts must continue to minimize greenhouse gas emissions and adapt to inevitable changes. In some cases, tipping points have already been passed, and nature requires a very long time to recover. Therefore, the decisions made in the current decade will be critical in determining what kind of Antarctica future generations inherit. Most importantly, it is necessary to support and strengthen the Antarctic Treaty system and not weaken its environmental norms. It is also necessary to expand scientific research, as very little is still known about many processes there. The melting point of ice is not open for debate, just as our commitment to preserving this continent.
Antarctica has no government, permanent population, or economy. Furthermore, since 1959, the continent has had no legally recognized owner due to the Antarctic Treaty, which freezes all territorial claims.
Essentially, this makes Antarctica the closest thing to Earth that is true public domain. However, in practice, about thirty countries currently operate over seventy research stations. Many of these stations are located close to each other.
One of these stations is equipped with a school, a chapel, a cemetery, and a civil registry office, which has registered eleven births since 1978. Nothing in this infrastructure is accidental, and much cannot be explained by science alone.
The construction and supply of a single research station costs millions of dollars in one of the planet's most logistically challenging locations. A country does not incur such expenses merely to measure atmospheric ozone, which can often be monitored from a closer location. In fact, the station serves to establish a presence in territory where such a presence is legally prohibited.
After decades of debate among geographers and geologists, the Brazilian Institute of Geography and Statistics (IBGE) established a new definition for what constitutes a mountain in Brazil, scientifically confirming the presence of this type of relief in the national territory.
Previously, the classification of Brazilian relief was a subject of controversy. The book O Homem e a Serra (The Man and the Mountain Range) (1963), written by engineer and geographer Alberto Ribeiro Lamego, already addressed the influence of terrain on the country's occupation, citing the difference between colonization in Rio de Janeiro and São Paulo. Lamego observed that the terrain dictated the paths of occupation, noting that in restricted coastal areas, settlers climbed the mountain range in search of land.
Although Lamego used the term 'mountains,' the classification remained disputed for many years. Many people learned that Brazil lacked mountains, associating them only with extreme elevations like the Himalayas or the Andes. However, geographical studies have evolved significantly since Lamego's initial work, culminating in a scientific consensus in 2026 that Brazil has mountains.
The modern concept of a mountain was initially imported from the United Kingdom in the 19th century. British cartographers defined a mountain as an elevation with at least 1,000 feet (304.8 meters) above the surrounding terrain, also requiring at least three steep slopes. This definition was adopted by professionals in other countries and is included in the Brazilian Geological Geomorphological Dictionary.
Professionals such as Lamego, Aroldo de Azevedo, Aziz Ab’Saber, and Francis Ruellan contributed to Brazilian studies. Initially, some geologists linked mountain formation to orogeny, the movement of tectonic plates, as occurs in the Andes and the Himalayas. However, since Brazil does not have active tectonism, this theory did not apply locally.
In 2019, Rosangela Botelho, an IBGE geographer, proposed a relief classification system similar to those used for soil and living beings, aiming to end terminological divergences. IBGE, in partnership with the Brazilian Geological Survey (SGB), the Union of Brazilian Geomorphology (UGB), and universities, formed a commission composed of about 70 specialists. This work resulted in the consensus that there are mountains in Brazil.
Lucas Krein Rademann, a geographer from UFSM, explains that what changed was the official understanding of what a mountain is, because before only formations linked to modern folding were considered. He points out that Brazil has large ancient mountain ranges that have been worn down by erosion.
The most accepted hypothesis suggests that Brazilian mountains arose not from plate movement, but from the uplift of the lithosphere. 480 million years ago, the territory had peaks comparable to the Himalayas, although temporal wear has reduced their altitude. Furthermore, a vertical movement of blocks formed the relief of the Serra do Mar 70 million years ago.
According to the new classification, 14 Brazilian states have mountains, with Minas Gerais registering the most, followed by Roraima. The IBGE commission also replaced the term 'depression' with 'lowered surface,' considering it imprecise, which is a crucial change since depressions cover 60% of the country.
The standardization of scientific understanding brings relevance to public policies, such as risk management and tourism. Rademann states that there will be changes in geography teaching, allowing areas classified as mountains to integrate into landslide prevention policies. Faria highlights that correct topography influences infrastructure planning and awareness of risk areas, in addition to valuing tourist destinations.
With the new definitions, locations previously classified as plateaus, such as the Serrana Region of Rio and the Guiana Plateau area, are now considered mountainous regions. However, Faria clarifies that Mount Roraima, despite being in the Guiana Plateau, should be seen as a large plateau due to its extensive area.
