LIFE SCIENCE

Detailed explanation-1: -Stable isotopes of oxygen (Oxygen [16O, 18O] and hydrogen [D/H]) are trapped in the ice in ice cores. The stable isotopes are measured in ice through a mass spectrometer.

Detailed explanation-2: -Ice cores: The ratio of oxygen isotopes in ice indicates the temperature at the time ice was deposited as snow. Also, air bubbles can be analysed to measure carbon dioxide and methane concentrations at the time the bubbles were trapped in the ice.

Detailed explanation-3: -Ice cores are cylinders of ice drilled from ice sheets and glaciers. They are essentially frozen time capsules that allow scientists to reconstruct climate far into the past. Layers in ice cores correspond to years and seasons, with the youngest ice at the top and the oldest ice at the bottom of the core.

Detailed explanation-4: -Ice-core analysis of volcanic ash indicates how eruptions affected past climates. Volcanic eruptions emit carbon dioxide, ash and other gases and underwater eruptions may warm climate by expelling water high into the atmosphere.