What does the layering in sediment cores typically represent?

The layering in sediment cores typically represents temporal changes in environmental conditions because each layer corresponds to a specific time period during which different conditions prevailed. Over millennia, the processes of deposition, erosion, and compaction create distinct layers that can be analyzed to interpret changes in temperature, ocean chemistry, ice cover, and even terrestrial influences like dust and pollen. This stratigraphy allows scientists to reconstruct past climates and ecological conditions, providing valuable insights into how the Earth’s climate system has evolved over time. The variations in thickness and composition of these layers reflect fluctuations in environmental factors, such as changes in sea level and biological productivity, thereby portraying a historical timeline of climate change.