Hydrology : Water temperature in a river Lucie Zimmlová Anglo-Czech High School České Budějovice - Czech Republic

Main ideas and aims of the worksheet: To get familiar with water temperature variability in a river To learn to search for data To learn to work with data To use GLOBE pages and other Internet pages

Structure of the worksheet Background Learning activities Formulation of the hypothesis Main task - basic part - more difficult part - conclusions Alternative task - a long-term project

Background Importance of water quality for organisms Relation of water temperature and water oxygen level

Learning activities 1. Practical measurements 2. Data search and making graphs - temperature - pH - conductivity...

Hypothesis “Does the water temperature usually increase or fall with the distance from the source?” Why?

Main task Part one (basic) Actual water temperature in a river Graph of water temperature distribution from the river source to the river outfall... Source of the data: Internet pages of hydrometeorological institute Using EXCEL

…reading the graphs “How many graphs do verify your hypothesis?” “How many graphs do reject your hypothesis?” “How many graphs do neither verify nor reject your hypothesis?” “Now, is your hypothesis correct?”

Main task Part two (more difficult) Source of the data: GLOBE database Two schools doing measurements in the same river !!!Are you sure??? - find “Water body name” - write to schools

Work with the data (basic) Graphs and tables of all water temperature data - the lowest temperature measured - the highest temperature measured...

Work with the data (advanced) Find a day of every month during one year that both schools measured water temperature in Fill the table …

Fill the table

Answer the question: “Does the data verify your hypothesis?” If not, try to tell why!

Conclusions (main task) “Does the water temperature usually increase or fall with the distance from the river?” “Why do the data appear that do not verify the hypothesis, although you had found out, that the hypothesis is right?” “Give a couple of suggestions of factors that can influence this!”

Alternative task - a long-term project Make various measurements from the source to the outfall of a river or a stream Observe animals and plants Draw maps, graphs, make tables... Make it public! Only if you know the river, you are able to protect it!!!

Teacher’s notes Subjects: biology, chemistry, geography Age: 12 to 18 Time needed (in computer lab): - part one: 45 min - part two: 60 min

Prerequisity Being familiar with EXCEL (or similar)

Recommendation Teacher should give an advice to the student which schools are appropriate for the task two: - making measurements in the same river - having enough data

Some factors that can influence temperature in a river Local weather (air temperature, rainfall…) Discharges e.g. from factories, power stations Affluents River depth Dams Rapids...

Water temperature in Vltava river 2002

Thank you for your attention! Do you have any questions?