Paleoclimate Data Puzzle How Do We Know What the Climate Was Like in the Past?

Key Terms to Understand Paleoclimate Proxy data Core Pollen Sediments Pond mud Unsorted sediments

Paleoclimate: Past Climates on Earth This figure shows annual air temperature simulated by the NCAR Community Climate System Model (CCSM3) for four different past time periods: a warm period approximately 250 Mya - the Permian-Triassic, a period of abrupt warming approximately 55 Mya - the Paleocene-Eocene Thermal Maximum, a glacial period approximately 21 kya - the Last Glacial Maximum, and a cold period approximately 500 years ago - the Little Ice Age. This image illustrates the large range of climates under natural forcings.

Proxy Data: Data that can be used to interpret past climates on Earth in the absence of someone being present to collect the data in real time. Examples include: Ice Cores: Ice cores contain dust, pollen, air bubbles, or isotopes of oxygen, that can be used to interpret the past climate of an area. Fossil Pollen: Inferences can be made about the climate based on the types of plants found in layers of sediment. Tree Rings: Since tree growth is influenced by climatic conditions, patterns in tree-ring studies reflect variations in climate. Ocean & Lake Sediments: cores of sediment from the floors of oceans and lakes contain materials that (preserved tiny fossils and chemicals in the sediments) that can be used to interpret past climate.

Core: A cylindrical sample of subsurface material extracted by a hollow coring tube driven into the subsurface, allowing collection of a sample that preserves layering and other structures.

Pollen: the sperm cells of plants Pollen: the sperm cells of plants. Pollen grains have a hard coat that protects the sperm cells during the process of their movement, and allows them to be preserved in sediments. Sediment: pieces of weathered rock that have been transported by wind or water and deposited at a new location. Unsorted sediments: an accumulation of sediments of varying particles sizes. Pond mud: very small particles of sediment that accumulate at the bottom of a quiet pond.

Key Ideas to Understand Range Maps: maps that have a system of identifying the area occupied by specific types of animals, plants or other such stuff. Deposition of sediments: When eroded and weathered particles of rock are transported by wind or water, they eventually settle out and form layers of sediment. Law of Superposition: A geologic principle to determine the relative age of layered sediment – states that the oldest layer will be at the bottom with successively younger layers above.

Range Map for Trees in North America

Sedimentary Rock Layers in the Grand Canyon Youngest rocks Oldest rocks

Allamuchy State Park, New Jersey