ENVS 3010 Lecture 3: Climate of the past
Document Summary
Climate was only reliably recorded since the 1880s: we need other methods than mechanical tools like thermometers to reconstruct the past climate. Are considered preserved physical characteristics found in the environment that indirectly give indication about the past climate. Provide an indirect measure compared to direct measurements obtained by modern instruments. Can be sorted into glaciological, geological, historical, and biological proxies. Why climate reconstruction: knowing about climate in the past gives us important information about how unusual current changes are. Climate proxies: things that give an indirect indication of past climate (approximations) Ice cores: a look in the past. The deeper in the ice the further in the past you are looking: ice samples removed from ice sheet. Most commonly from antarctica or greenland: climate information. An atom with the same atomic number but different mass number. Number of protons identify the element (atomic number) How heavy the element is the number of protons and neutrons combined (atomic mass)