Oxygen-18 has been frequently used in Palaeoclimatology to measure / estimate climate changes in the history of Earth. Consider the following statements in this context: It helps in measuring the average atmospheric temperature Water molecules containing the heavier O-18 evaporate at a higher temperature When temperature increases the Ratio of O-18 to O-16 will be higher Which among the above statements are correct ?
Q. Oxygen-18 has been frequently used in Palaeoclimatology to measure / estimate climate changes in the history of Earth. Consider the following statements in this context: It helps in measuring the average atmospheric temperature Water molecules containing the heavier O-18 evaporate at a higher temperature When temperature increases the Ratio of O-18 to O-16 will be higher Which among the above statements are correct ?
Answer: 2 & 3 only
Notes:
  1. It helps in measuring the average atmospheric temperature - This statement is incorrect. Oxygen-18 is used to estimate ocean temperatures rather than atmospheric temperatures directly.
  2. Water molecules containing heavier O-18 evaporate at a higher temperature - This statement is correct. The oxygen isotope ratio provides information about evaporation temperature of the water.
  3. When temperature increases the ratio of O-18 to O-16 will be higher - This statement is correct. Higher evaporation temperature leads to increased fractionation of the heavier O-18 isotope, increasing the O-18/O-16 ratio.

 

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