Final answer:
Proxy records, including fossil plant remains and pollen cores, are geological and biological evidences used by scientists to interpret past climates. These secondary sources provide insights into the relative temperature, vegetation, and environmental conditions that prevailed in different geologic periods.
Step-by-step explanation:
Proxy Records in Geology and Paleoclimatology
Geologists and paleoclimatologists often rely on proxy records to understand past climates since direct measurements are not possible. These proxies include fossil plant remains, pollen cores, ice cores, and other geological evidence. A well-known biological proxy is the foraminifera, whose coiling direction can indicate relative seawater temperature during its lifetime. Pollen grains also act as climate proxies; with their resistant shells, they are well-preserved and abundant in the geologic record. This allows scientists to trace plant species and migrations, revealing climate changes throughout history.
Fossil plant remains and animal fossils are also key in reconstructing past climates and environments. These remains help indicate the type of climate of an area during different periods, giving clues to patterns such as precipitation and temperature. For example, fossils of palm trees suggest subtropical climates similar to present-day Florida during the Eocene epoch, corroborating other data like oxygen isotope records.
Sediment records are another important proxy. They not only contain fossils but also have physical characteristics like grain size and provenance that inform geologists about past climate conditions. In combination with other proxies, a cohesive and comprehensive picture of earth's climate history is constructed, aiding in our understanding of climate change.