Describe three methods used to study past climates

Question

What will be an ideal response?

Answer 1

Answer: Ocean deposits: Scientists extract cores of the ocean-bottom material, note the isotope ratios, and infer past changes in global ice volume. Remnant landforms: There are several mechanisms for eroding and depositing material, including the movement of water, the slow-moving ice sheets expanding across the surface, wave action along coastlines, wind, and floating icebergs carrying land debris. Each of these mechanisms leaves certain telltale characteristics, and trained field scientists can use the evidence to infer climatic conditions at the time of erosion or deposition. Coral reefs: Because they exist along shallow waters, relic coral reefs can provide information on the location of past sea levels. Moreover, because the chemical composition of growing coral is affected by the water temperature, analysis of the changing chemistry of coral reefs with depth provides useful information on past conditions.