Paleoclimatology is the study of ancient climates. A region's present day or ancient climate is determined by taking several factors into account, including characteristics of the region’s atmosphere, hydrosphere, lithosphere, and biosphere. Since direct observations of ancient climates are not available before the 19th century, paleoclimatologists rely remnants of evidence, such as sediments found in lake beds, ice cores, and tree rings. This information is then used to create mathematical climate models. Why do you think it’s important for scientists to study Earth’s past climates? What information are scientists likely to gain from investigating the Earth’s past? Since the data obtained by paleoclimatologists is not based on direct observations, can their discoveries and models be trusted? Why or why not?