Humans have been significantly impacting the Earth in what's now called the Anthropocene Era for about 70 years. To understand this new geological time period, scientists are using detailed annual growth layers and other markers to date it accurately. This helps researchers characterize the recent changes to the planet caused by human activities in a way that's different from traditional geological dating methods used for much older rock layers. This new approach lets scientists study our impact on the Earth in a more precise and focused manner, providing valuable insight into the effects of human actions on our planet.