Question

Which do scientists study to determine air temperature at the time it was formed? Select the two correct answers. (1 point)
Responses

chemical isotopes in foraminifera shells
chemical isotopes in foraminifera shells

tree rings
tree rings

fossilized pollen
fossilized pollen

ice formed thousands of years ago
ice formed thousands of years ago

Answer 1

To determine air temperature at the time it was formed, scientists study:

1. **Chemical isotopes in foraminifera shells** - These microscopic organisms have shells that can provide information about past ocean temperatures based on the ratios of oxygen isotopes.
2. **Ice formed thousands of years ago** - Ice cores from glaciers and polar ice caps contain layers that preserve bubbles of ancient atmosphere, allowing scientists to analyze past temperatures and greenhouse gas concentrations.

So the correct answers are **chemical isotopes in foraminifera shells** and **ice formed thousands of years ago**.