4.1 The Hydrological Cycle Challenge
The Hydrological Challenge
Students are very familiar with the water cycle and so the challenge for a teacher is to take them beyond what they know, or think they know. Students can mostly draw a version of the water cycle without studying this topic and it will probably contain lots of pretty pictures of mountains and rivers and clouds etc. This activity asks them to use more technical language, and to convert the traditional water cycle into a detailed system diagram showing stores, transfers and transformations.
The ESS guide specifies which flows and storages students should be able to identify and explain. Students should also be able to explain that the sun's solar energy drives the hydrological system as this energy causes water to evaporate, condense or precipitate and also creates the differences in pressure which result in winds that move the water around the atmosphere.
In these videos, the Hydrological Cycle is explained simply but with advanced language. Watch the video then in groups draw a systems diagram / flow chart of the hydrological cycle using system symbols such as boxes and arrows, and the correct vocabulary. Your teacher may turn this into a competition to see who can use the most correct terms and visual language.
Here is a diagram I prepared
Part 2 - The Human Impact on the Hydrological Cycle
Watch the presentation and then annotate your hydrological diagrams with information about how humans impact the hydrological cyle. Be creative - you don't need to stick to systems terminology now.
Understanding the role of forests and deforestation on local, regional and global precipitations
Here are some questions to go with the video
1. what is the process wherby plants release water vapour into the atmosphere?
Transpiration
2. What can happen to this water vapour eventually?
It can fall back locally or be transported globally
3. Give one countrymentioned in the video that will receive water that has been transferred from the Amazon rainforest
Argentina
4. What happens to transpiration with the loss of forests?
It declines