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Gas is trapped in polar ice sheets at ∼50-120m below the surface and is therefore younger than the surrounding ice. Firn densification models are used to evaluate this ice age-gas age difference (Δage) in the past. However, such models need to be validated ...
The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these polar regions covered by sea ice, the wind is relatively strong due to the absence of obstructions and redistributes a large part of the depos ...
The stable carbon isotopic signature of carbon dioxide (δ13CO2) measured in the air occlusions of polar ice provides important constraints on the carbon cycle in past climates. In order to exploit this information for previous glacial periods, one must use ...
The large, rapid increase in atmospheric N2O concentrations that occurred concurrent with the abrupt warming at the end of the Last Glacial period might have been the result of a reorganization in global biogeochemical cycles. To explore the sensitivity of ...
Fundamental for the understanding of processes involved in climate change is the knowledge about its temporal and spatial evolution. Of special interest is the relation between high-latitude polar sites since they are a major component in climate change. I ...
Polar ice sheets and mountain glaciers, which cover roughly 11% of the Earth's land surface, store organic carbon from local and distant sources and then release it to downstream environments. Climate-driven changes to glacier runoff are expected to be lar ...
The analysis of air bubbles trapped in polar ice has permitted the reconstruction of past atmospheric concentrations of CO2 over various timescales, and revealed that large climate changes over tens of thousands of years are generally accompanied by change ...
Analysis of air trapped in polar ice provides the most direct information on the natural variability of Greenhouse Trace Gases (GTG). It gives the context for the dramatic change in their atmospheric concentrations induced by anthropogenic activities over ...
In relation to Arctic warming, the possible occurrence of methane hydrate degassing events has attracted an increasing interest in recent years. We evaluate the atmospheric impact of rapid and massive emissions of methane and how they are imprinted in ice ...
Air trapped in ice core bubbles provides our primary source of information about past atmospheres. Air isotopic composition (15N/14N and 40Ar/36Ar) permits an estimate of the temperature shifts associated with abrupt climate changes because of isotope frac ...
