Question

Which do scientists study to determine air temperature at the time it was formed? Select the two correct answers.

Answers:

tree rings
fossilized pollen
ice formed thousands of years ago
chemical isotopes in foraminifera shells

Answer 1

Scientists study the following to determine air temperature at the time it was formed:

1. **Tree rings** - The width and density of tree rings can indicate the growth conditions, which are influenced by temperature and precipitation.

2. **Chemical isotopes in foraminifera shells** - The ratios of oxygen isotopes in foraminifera shells found in sediment cores can provide information about past sea temperatures, which are related to air temperatures.

Fossilized pollen and ice formed thousands of years ago can provide climate information as well, but the two selected answers are more directly related to determining air temperature at the time of formation.