Con sus menos 50° C de temperatura media invernal que el 21 de julio de 1983 en la estación rusa de Vostok, la Antártida alcanzó el valor récord de menos 89,6°C, una densidad habitacional que durante la larga noche austral es igual a 13.000 km² por habitante y que se vuelve de “apenas” 1700 km² en el período estival, sus montañas que alcanzan los 5400 metros de altura, la Antártida es un laboratorio único en su género donde se estudia el estado de salud del planeta, se reconstruye su pasado y se formulan nuevas hipótesis para su futuro.
El término Antártida fue acuñado por los antiguos griegos en el siglo VI antes de Cristo: Antarktikos era el hemisferio opuesto al que contenía la constelación de la estrella Polar, la Osa Menor o Arktikos. Mientras que a los filósofos, desde Pitágoras hasta Aristóteles, corresponde el mérito de haber imaginado la Tierra esférica.
En el siglo II después de Cristo el astrónomo y geógrafo Claudio Ptolomeo retomando las hipótesis griegas pensó que para contrarrestar el peso de las tierras presentes en el hemisferio norte debía necesariamente haber un continente también en el hemisferio sur. Pero aún por mucho tiempo se fantasearía sobre la existencia o no de una tierra en el Polo Sur. La primera representación de las costas de la Antártida data de 1513, cuando el almirante turco Piri Reis publicó una carta del Atlántico en la que, al sur de la Tierra del Fuego, aparece una costa desconocida que replica de manera increíble el perfil de la Antártida como probablemente era antes de su glaciación. En 1569 el flamenco Gerhard Kremer, más conocido como Gerardus Mercator, el padre de las proyecciones cartográficas aún hoy usadas para la navegación plana, dibujó en la parte sur de su globo un vasto continente, de perfiles imaginarios y que cubría por completo la capa polar: la Terra Australis Incognita. El primer navegante en desafiar los cuarenta rugientes y los cincuenta aulladores fue James Cook, quien cruzó el círculo polar antártico en 1773.
Pero el primer avistamiento verdadero fue el del 27 de enero de 1820, cuando una expedición comandada por el estonio Fabian Gottlieb von Bellingshausen a bordo del Vostok navegó a unas veinte millas de distancia de la costa antártica. Mientras que el capitán americano John Davis fue el primero en desembarcar en el Continente el 7 de febrero de 1821. Después de esa fecha habrá muchas otras expediciones, algunas terminadas trágicamente otras de manera triunfante. Todas sin embargo contribuirán a la conquista del último lugar desconocido del planeta.
The South Pole
But the South Pole is not only the historical memory of our geological evolution, it is also a reliable thermometer that constantly records the level of pollution on the planet. From this privileged vantage point, in fact, thanks to a dense network of both manual and automated detectors, the size of the ozone hole and the extent of the greenhouse effect are accurately monitored. But that’s not all. From here scientists carry out important cosmological research, such as the study of ionized hydrogen particles coming from the sun that interact with the “Earth’s magnet” causing the so-called magnetic storms. They also perform astronomical observations in the millimeter and infrared bands to capture the cosmic background radiation, which is the residue of the energy released during the Big Bang, in the hope of shedding light on how galaxies are born and what happened during the first moments of the Universe’s life.
The Antarctic Treaty
Legally, the Ice Continent is governed by an international neutrality pact, the Antarctic Treaty, which suspends any territorial claims south of the 60th parallel, prohibits all kinds of military and nuclear experiments, promotes the development of international scientific cooperation, and ensures the conservation and protection of flora and fauna throughout the territory. The treaty was signed in Washington on December 1, 1959, by twelve of the forty countries participating in the International Geophysical Year of 1957-1958 and came into force in 1961.
With that document, the South Pole was given a legal system that “internationalized” the Continent, “freezing” the problem of those States that for strategic interests claimed sovereignty. However, the agreement lacked any reference to the possible economic exploitation of energy and natural resources, and its duration was set at thirty years, at the end of which all agreements could be reconsidered by any contracting State and thus renegotiated. Such a “flexible” arrangement was perhaps dictated by the fact that rumors were already circulating at the time about possible hydrocarbon deposits identified between the Weddell Sea and the Ross Sea.
These rumors were founded, given that in 1973 New Zealand, Japan, and the United States, thanks to a drilling project started in the Ross Area, found under a crust of ice hundreds of meters thick oil reserves estimated at 40 billion barrels. The news opened new and disturbing political and economic scenarios just as the great energy crisis of the late 1970s was looming on the horizon. Thus, there was a real rush to Antarctica by those states that at the time of signing had been left out of the Treaty.
It was necessary at all costs to be part of the elite group in order to have subsequently the right to exploit that immense territory that hid who knows what mineral and oil resources, or to be able to fish freely in its icy waters tons and tons of krill, a small and nutritious shrimp, as indispensable to the Antarctic fauna food chain as interesting for the livestock and food industry.
Not to forget that the Antarctic ice sheet contains 91% of the planet’s ice, or 68% of the freshwater reserves. This figure takes on enormous economic importance when considering that the population increase recorded between 1900 and 1995 has sextupled the planet’s freshwater consumption and thrown at least a third of the world’s population into a water emergency.
Antarctic Treaty System
To curb the economic and territorial ambitions of many countries, the Antarctic Treaty System was born, and alongside the Pact signed in Washington were added the CCAS, the Convention for the Conservation of Antarctic Seals in 1978, and in 1980 the CCAMLR, a convention for the protection and conservation of Living Marine Resources of the Antarctic Seas. A few years later, however, another Convention was enacted in Wellington that authorized and regulated the exploitation of mineral resources in Antarctica.
The Madrid Protocol
Then the Madrid Protocol, signed in 1991 and entered into force on January 14, 1998, finally banned all types of mining exploitation for the next 50 years and requires operating nations to assess the environmental impact of any activity. The document thus puts an end to all economic ambitions and defines Antarctica as “a natural reserve devoted to peace and science”.The Antarctic Treaty has so far been signed by 45 nations representing more than 80% of the world population.
The reasons that led to the establishment of the Geophysical Year in 1957 were the same as those that led to the organization of the first and second International Polar Years, respectively in 1883 and 1932-33: to discover Antarctica, its resources, and its secrets. The next International Polar Year will be held in 2007.
The event was promoted by the greatest scientists in the world to rationalize human and economic resources and to carry out a vast study project on the Earth’s magnetism and the upper atmosphere. On that occasion, Scar was established, the Scientific Committee on Antarctic Research, with the specific purpose of coordinating research in Antarctica. The project marked the beginning of the exploration of the sixth Continent and, with the launch of the first artificial satellite, also the space age.
About ten thousand men from twelve different nations took part in that massive expedition, the largest in exploration history, and installed forty scientific stations distributed across the entire polar ice cap.
Before that initiative, there were only about ten permanent bases in Antarctica, primarily operated by Americans and Soviets. With the programs organized by Agi, however, a broader research activity based on international cooperation and sharing of collected data began. Today, Antarctica counts 68 international and interdisciplinary scientific bases.
EPICA, le projet européen de forages glaciaires en Antarctique
Depuis lors, plus de quarante années d’études ont permis de collecter une énorme quantité de données et les derniers résultats importants obtenus concernent le projet EPICA, le European Project for Ice Coring in Antarctica. EPICA est un programme de forage profond dans la glace auquel ont participé dix pays, réalisé sur le site de Dome C, à proximité de la station Concordia, à 3230 mètres d’altitude et à plus de 1000 kilomètres de la côte. L’activité de carottage a commencé en 1996 et s’est achevée le 21 décembre 2004 en extrayant d’une profondeur de 3270,2 mètres une carotte de glace datant d’environ 900 000 ans. Grâce à toutes les carottes forées durant l’expérience, les scientifiques disposent désormais d’informations climatiques détaillées et continues couvrant une période d’environ 10-12 cycles glaciaires-interglaciaires alternés, chacun d’environ cent mille ans. Cette très longue photographie climatique de la planète s’est formée avec la stratification de la neige tombée en Antarctique au fil des millénaires.
La neige glacée a emprisonné et archivé les informations atmosphériques contenues dans les particules de gaz présentes dans l’air au moment de sa déposition. L’étude des échantillons permet de reconstituer la composition de l’atmosphère aux différentes époques, l’évolution de la température à la surface de la Terre et les changements climatiques survenus depuis lors jusqu’à aujourd’hui, comprenant également dans quelle mesure la pollution provoquée par l’homme a influencé le climat.
La carotte de glace, longue de plus de trois kilomètres, n’a pas encore été entièrement examinée, mais les premiers résultats ont déjà apporté d’importantes nouveautés : tout d’abord, de l’analyse des couches les moins profondes, c’est-à-dire celles qui enregistrent les événements du dernier siècle, une réduction du plomb et des chlorofluorocarbures, le fameux CFC responsable de l’amincissement de la couche d’ozone, a été constatée, tandis que les hydrocarbures aromatiques polycycliques contenus dans l’essence sans plomb ou produits par la combustion des déchets et les systèmes de chauffage ont augmenté.
La concentration de dioxyde de carbone, responsable de l’effet de serre, n’a jamais été aussi élevée qu’aujourd’hui au cours des 440 000 dernières années.
D’autres données issues de la lecture de la carotte extraite à Dome C concernent la température et la durée des périodes chaudes et froides causées principalement par des phénomènes astronomiques, tels que les modifications imperceptibles de l’orbite de la Terre autour du Soleil et de l’inclinaison de son axe de rotation, qui entraînent des variations de la quantité d’énergie solaire atteignant les hautes latitudes. L’étude des échantillons examinés a montré que des températures similaires à celles d’aujourd’hui ont déjà existé ces 400 000 dernières années, mais pas avant, que les périodes chaudes comme la nôtre ne représentent que 5-10 % de la période étudiée et que la période interglaciaire chaude actuelle, commencée il y a 11 500 ans, devrait durer au moins encore 13 000 ans, à moins que l’homme n’y mette son grain de sel. Ainsi, le cauchemar d’une nouvelle ère glaciaire imaginée dans le film « The day after tomorrow » semble, pour l’instant, écarté. Toutefois, même si rien de catastrophique ne se profile à l’horizon, les chercheurs suggèrent de surveiller l’action humaine sur le climat et l’environnement et d’évaluer les mutations du cadre climatique général sans alarmisme mais certainement avec un réalisme scientifique.
The Swiss Polar Research Commission, CSP
The Swiss Polar Research Commission, CSP, also participated in the Epica project. During the 28th SCAR meeting held in Bremerhaven from October 3 to 9, 2004, the CSP received international recognition for the work carried out in Antarctica, and thanks to the important results obtained at Dome C by scientists from Swiss universities, the Swiss Confederation became a full member of the Scientific Committee on Antarctic Research.
Up to 140 million years ago, Antarctica was part of the supercontinent Gondwana, which included Africa, Arabia, India, Australia, New Zealand, and South America. At the end of the Jurassic, the breakup of the supercontinent began, and about 20 million years ago Antarctica completely detached from the other lands to slowly occupy the polar ice cap. A drift that lasted millions of years, theorized in the 1920s by Alfred Wegener, the German scientist who reconstructed the shape of Pangea, and only in 1950, with the development of geological mappings of the seabeds, was supported by scientific evidence.
