Answer:
To study ancient climates using ice, scientists use data from polar mountain glaciers.
Explanation:
From the analysis and interpretation of natural traces, scientists describe the climate for hundreds to millions of years. Data derived from tree rings, ice cores, corals and ocean sediments, caves, among others, are observed. It is possible to gather these data with geophysical or biological measurements and some reconstructed climatic variables, such as temperature and rain level.
Polar mountain glacier data can be analyzed in laboratories to measure the amount of oxygen and methane, in addition to other parameters that help to indicate climatic variations. NASA researchers started Paleoclimatology in the 19th century, studying precisely the expansion of ice caps.
