Nature’s File Cabinets
When researchers want to understand the history of the environment, they extrapolate data from oral histories or peruse digitized weather observations, aging diaries and farmers’ journals. But these records are spotty, subjective and only go back a few centuries. So scientists also look to the Earth itself and the vast timeline hidden therein — the natural archive.
These storehouses of earthly data — ice cores, seafloor sediments, oyster shells, even road cuts through layers of rock — offer a far deeper look back in time than human records. A researcher can extrapolate water-quality data by examining river sediment, or determine forest fire frequency and magnitude through the rings of a tree.
As with any archive, scientists must learn to read the natural archive’s language in order to understand what it is saying. Translations constantly evolve, meaning that interpretations do as well. And
