You're likely thinking about tree rings. They are a great way for scientists to learn about past weather conditions, but not directly from "rings" in the traditional sense.

Here's how it works:

* Tree growth: Trees grow in a pattern of distinct layers, much like rings. Each layer (or ring) represents one year of growth.

* Growth influenced by weather: The width of each ring depends on the amount of rain, sunshine, and other environmental factors present in that year.

* Analyzing the rings: Scientists can study the thickness, density, and other characteristics of the rings to determine the climate conditions during the tree's lifetime.

So, tree rings provide scientists with information about past weather conditions in the area where the tree grew.