Climate in Concordia (Antarctica)

In the Franco-Italian station of Concordia the climate is polar, with extremely low temperatures and always below freezing.
The station is located at 75 degrees south latitude, in one of the ice domes of Antarctica, called Dome C (Dome Circe, Dome Charlie or Dome Concordia), at 3,233 meters (10,607 feet) above sea level. The ice cap beneath the station is 3,270 (10,728 ft) meters thick, but in other areas it is 4,000 meters (13,100 ft) thick, which means it goes below sea level.
We are in the East Antarctic Plateau, the coldest and driest area of ​​the continent, the same as the Vostok station, which is located about 550 kilometers (340 miles) to the south-west. The sea is at least 950 km (590 mi) away.
From October to March, the station receives supplies by a land convoy from the French base of Dumont d'Urville, located on the coast, 1,100 km (685 mi) away, while personnel are transported by air. The personnel who stays in the station during the winter, around 15 people, will remain isolated, without flights or supplies, in a condition reminiscent of that of the orbital space station.
The current Concordia station was built in 2005, but since December 1995 there has been an automatic station, called Dome C II, which collects meteorological data. Furthermore, since 1985 there has been another automatic station, called Dome C, and located 70 km (43.5 mi) further north.



Of the three inhabited Antarctic stations located on the plateau, Concordia is intermediate both in terms of altitude and temperature. The annual average in the Concordia station is in fact -50.6 °C (-59.1 °F), compared to -48.6 °C (-55.5 °F) at the South Pole (Amundsen-Scott station), which is located at 2,800 meters (9,185 ft), and -54.5 °C (-66.1 °F) at Vostok, which is located at 3,500 meters (11,500 ft).
Winter at the Concordia station, as generally in the inland areas of Antarctica, lasts from April to September. It is interesting how, due to atmospheric circulation, the coldest month here is even May. On the Antarctic plateau, the coldest months, as well as the coldest periods, are those in which the air masses move the least, and there are no intrusions of milder air from the ocean.
During cold spells, temperatures can drop to around -80 °C (-112 °F). The coldest record is -84.7 °C (-120.5 °F), set in August 2010. In 2010, the winter was particularly cold, and the monthly average in July was -69.7 °C (-93.5 °F).
Summer corresponds to the months of December and January.
The temperature never exceeds the freezing point, and at most, it can occasionally drop to around -10 °C (14 °F). In 2022 it reached -10 °C (14 °F) in March, a value 37 degrees Celsius (66 °F) higher than the average maximum for that month.
Here are the average temperatures.

Precipitation at the Concordia station is decidedly low. The equivalent amount of ice (measured after melting) that accumulates each year is 25 millimeters (1 inch), while the estimated amount that actually falls is around 100 mm (4 in) per year. In any case, it is very difficult to measure precipitation in these conditions, because the snow, light and powdery, is often carried away by the wind, while more is brought in from other areas. Furthermore, the formation of hoarfrost can create further accumulation which, however, is not due to snowfall.
Given the low temperatures, precipitation occurs mostly in the form of "diamond dust", i.e. tiny needles of ice, which can form even with clear skies, due to the direct condensation of the little humidity present in the air. More rarely, snow or sleet may fall.
The wind at the Concordia station, and in general on the Antarctic plateau, is much less intense than in the peripheral areas, where the terrible katabatic winds blow, rushing towards the ocean with hurricane force.



In Concordia station the polar night, in which the sun never rises, lasts from May 7th to August 8th. It should be said that for a few weeks, at the beginning and end of this period, the sun approaches the horizon around midday, providing some light.
The polar day, in which the sun never sets, runs from October 31st to February 10th. Furthermore, for a few weeks, before and after this period, the sun remains near the horizon even at midnight, providing some light, so the so-called "white nights" occur.
At the summer solstice, December 21st or 22nd, at midday the sun reaches 38 degrees above the horizon, that is, 14 and a half degrees higher than at the South Pole.

In this and other Antarctic stations, with an icy surface, scientists carry out core samples to study the chemical and physical composition of the ice layers that have accumulated over the millennia. This allows us to reconstruct the climate of the past, up to around 800,000 years ago.
The clarity of the air and the high frequency of clear skies are an excellent basis for astronomical observations, in fact the station also has a telescope. Furthermore, due to its proximity to the magnetic south pole, the area receives a large amount of solar and cosmic rays, so there are also instruments to detect them.