A lesson in which students analyze the chemical data that led researchers to conclude that the K-T boundary layer contained an extraordinary concentration of iridium.
A worksheet in which students calculate how much iridium was released, and eventually deposited all over the Earth, by the impact of the asteroid that caused the K-T extinction.
Earth has been both cooler and warmer in the past, but the change is usually gradual. The current rate of carbon dioxide increase is unprecedented in human history, and solutions to mitigate its effect on global warming are challenging to implement.
Explore the changes in oxygen levels throughout Earth’s history and discover their impact on life.
This activity guides students through building a conceptual model of how carbon dioxide affects Earth's climate