Q. Consider the following statements regarding the use of Oxygen-18 (O-18) isotope in paleoclimatology:

1. Water molecules containing heavier O-18 isotope evaporate at a higher temperature than those with Oxygen-16 (O-16).
2. An increase in temperature leads to a higher O-18 to O-16 ratio in ice cores, aiding in the estimation of past climate changes.

Which of the above statements is / are correct?
Answer: Both 1 and 2
Notes: Ice cores preserve isotopic records of past climates. Water with heavier O-18 evaporates less readily than O-16, so O-18 in precipitation is relatively enriched during warmer periods. Thus, higher O-18 to O-16 ratios indicate past warmer temperatures, allowing reconstruction of climatic shifts over geological time through isotopic analysis of ice cores.