Investigating the Hydrosphere
No matter the scientific discipline, your students can benefit from a study of water.
By Lynsey Peterson
Of all the systems on Earth, you could argue that the hydrosphere is the most important. Water is what makes the planet habitable and sets it apart from other planets. Even Earth’s nickname, The Blue Planet, is a reference to the abundance of water on its surface. I teach about different parts of the hydrosphere in all of my classes.
Every scientific discipline can feature a unit on water. In earth science, we discuss the water cycle through a simulation. I set up stations representing different parts of the water cycle, such as the ocean, rainwater, groundwater, and atmospheric water vapor. At each station is a die with six different conversions that the water at that location can undergo. Each student acts as a drop of water. They start at any station, role the die, and follow the instructions to move through the cycle. As they move around the room, simulating the movement of water, they write down the conversions. At the end of the exercise, they write a story or a comic strip about their water cycle. This activity emphasizes that the water cycle is a continuous conversion and movement of water throughout Earth’s other systems, not just some circular diagram to memorize.
Water also shapes the land. Students can view pictures of actual landforms, such as the Grand Canyon, and discuss how water created them. Of course, the transformative power of water doesn’t only apply to Earth Science. Modeling a watershed in a pan helps my environmental science students understand how water moves in response to the land and in turn shapes the land itself. This is also a great way to introduce contour lines and topographic maps. In physics, students can investigate the phase transition of ice into water under various temperatures and pressures.
My chemistry and biology students don’t miss out on a water unit either. The unique chemical properties of water make it essential to life. Chemistry students can research hydrogen bonding and its effects on water’s properties, such as water’s high melting and boiling points. Biology students can research the role of water in living organisms or in their own bodies. An investigation of the pH scale is also an important part of understanding water chemistry.
Whatever subject you teach, you can help your students grasp the importance of the hydrosphere. Try some of these other ideas as well!
Investigating the Hydrosphere Lesson Plans:
Students examine the water cycle and trace the flow of energy produced. Heat transfer operating in each process of the water cycle is identified. The learner investigates the role of the Sun in the process.
Students describe the changes that have affected the Missouri River over the past 200 years by identifying transformations in this area's atmosphere, biosphere, hydrosphere, and lithosphere. They research online in groups assigned to each topic.
Students explore the components of a watershed and the factors that affect it. They read a topographical map and use geometry to determine the area of a watershed. Students estimate the volume of a body of water and perform runoff calculations based on the surface area.
Students distinguish between polar and non-polar covalent bonds. They illustrate the three kinds of weak bonds using a drawing board and demonstrate how water molecules form hydrogen bonds. They draw a water molecule on a one-foot square drawing board.
Students examine and calculate the percentage of potable water remaining on the earth. In this ecology and geography lesson, students brainstorm the main factors affecting water distribution. Students use mathematical problem solving to calculate the approximate amount of usable water available on earth.
Students explore the different properties of water. They experiment with different activities, each one explaining a different property of water. Students read an article "Small, Yes, But Mighty: The Molecule Called Water," and then complete the experiments.
Students investigate the properties of water and focus upon its chemistry. They focus upon the specific heat, heat of fusion, capillary action, cooling and heating rates, universal solvent, conductivity and pH. They conduct experiments to collect data for analysis.