![]() As it densifies, the porosity between the snow grains gradually decreases, trapping a sample of atmospheric air. When the snow sinks deeper into the glacier, it is made denser by the weight of the successive layers above it. Accurately measuring the proportions of heavy and light isotopes in the water molecules offers a window to the temperature conditions or the amount of precipitation at the time the snow was deposited. The oxygen and hydrogen of the water molecules in snow come in different forms, known as ‘isotopes’, some of which are heavier than others. Its presence in greater or lesser quantities gives us an insight into the quantity of snowfall over time, as well as changes in solar activity or the intensity of Earth’s magnetic field. It is produced in the upper atmosphere from the interaction of solar wind with nitrogen molecules. It is an extremely rare element, with measurements showing only around 10,000 atoms per gram of ice. Other naturally occurring radioactive elements can also be measured in the ice – for example, beryllium-10. Closer to home, the Chernobyl disaster also left its mark on the Alpine glaciers, causing a peak in caesium-137. Consequently, radioactive elements produced by thermonuclear tests conducted during the 1950s and 1960s can be found. Dissolved in snowflakes or attached to tiny clay particles carried by the wind, these pollutants are seen by diffusing an emission of beta or gamma radioactivity. Radioactive pollutants can also leave traces in high-altitude snow. The term ‘aerosols’ is used to refer to tiny droplets comprising, for example, acids: sulphuric acid from coal combustion, nitric acid emissions from agricultural soils or the conversion of nitrogen oxides emitted by cars or heating sources, hydrofluoric acid emitted by certain industrial activities and organic acids resulting from natural emissions of organic compounds from plants, the burning of those plants or the burning of fossil fuels, etc. lead, zinc, copper, platinum, rhodium, palladium, etc.). Among the solid particles, those released by human activities can also be found, such as heavy metal particles (e.g. Successive layers of fresh snow then carry these layers of dust down into the icy depths. This dust has crossed the Mediterranean Sea before being partly deposited on the surface of the glaciers. ![]() As a result, Alpine glaciers contain dust-enriched layers originating from intense sandstorms in the Sahara Desert. These impurities may be solid, such as dust released by soils or deserts. Made up almost entirely of water molecules, these snow layers also contain impurities, which sometimes represent just a few millionths of billionths of the mass of snow deposited. Their bet is that their successors will develop new ideas and techniques to enable the ice to reveal and highlight new data Recording the environmentĪs layers of snow are deposited on the surface of a glacier, they record a wealth of information about the state of our environment. While, first and foremost, ice cores make it possible to build a timeline for the climate and environment archive that they represent, scientists are also able to take advantage of numerous tracers providing information on the state of the environment and climate. This analysis phase will be performed by scientists involved in the Ice Memory Foundation in collaboration, if possible, with young researchers from those countries where ice cores have been extracted from in order to develop their skills. Freely accessible, this database will be useful for research by the current scientific community and it will also serve as a reference for future scientists. The results will be shared within a database as detailed and exhaustive as possible. The objective of Ice Memory Foundation is to preserve glacial archives so that in the future researchers can conduct their own research programs on preserved ice cores with the new techniques and processes they will have developed.
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