1 What does evaporation tell us about ice ages?

2 p. 608 Reflect & Connect 1-4 Finish up from the other day. 2

Listen to Alex explain the demo. Based on what you think might happen, develop a data table with your team to record your data. Your table needs to include a column expressing the number of heavy objects to light objects as a ratio. Analyze your data by calculating the initial and final ratios of heavy to light objects in the box. Be prepared to share these data with your class.

What did this demo represent? In this water evaporation model, what does the plastic box represent? What do you think the heavy objects represent? The light objects? What does the tapping represent? In this model, which water molecules (heavy or light) are more likely to evaporate? Why? What happens to the water that evaporates? Where does it end up?

What will happen to the ratio of heavy to light water molecules in the ocean during a glacial period? Read “Water: Is It All the Same?” pp

Answer # 7 on p 611. To definitively answer the QOD: explain how the model relates to water evaporating from the ocean during glacial and interglacial periods, explain what happens to the ratio of heavy to light water in the ocean during glacial and interglacial periods, include a diagram or sketch showing the relationship to the water cycle, and use evidence from your investigation to support points in your summary.