Exploring an understanding of the difference between weather and climate... 

The Climate Shuffle

Math skills needed:  suitable for students learning to average and graph.

We know from personal experience that weather is highly variable, from day to day and from one season or year to the next. How can we begin to see a temperature trend in climate of a single degree Celsius, when we can sense changes in temperature of an order of magnitude or more than that in a single day?

Statistically, climate is expressed as weather conditions averaged over a period of years. Often a 30-year interval is employed for analytical purposes when describing climate trends. Climate change is described as a positive or negative trend in data observed in one or more climatic variables over the time interval being examined. The long-term average has to change enough to be statistically meaningful to be interpreted as climate change.

To explore this idea, we will build a mental model and conduct a simulation of how climate changes.

Materials needed:

• a standard card deck (52 cards)
• graph paper or software

In this simulation, use a standard deck of 52 cards.

Each card represents a year, and the value of the card will determine whether that year was warmer or cooler than average:

Black cards are cooler than average years

Red cards are warmer than average years

Face cards, regardless of color, are years with average temperature.

The simulation:

1. Shuffle deck and select 30 cards.
2. Turn over the cards, one at a time. As you do so, make a graph of warmer and cooler years. Its up to you how you choose to "crunch your data" and graph it.
3. Repeat this experiment 5 times. Can you identify periods that might be considered multi-year heat waves or multi-year cool periods? Identify and explain.
4. After conducting one 30-year simulation, remove 2 black cards from the deck, and deal 30 cards out a second time. By removing the "cooler than average" we are simulating a hypothetical warming climate change scenario.
5. Repeat steps 1, 2, and 3 for 5 or more deals.

Answer the questions below, and post to the discussion board:

1. Upload your graph to the discussion board!
In your simulation, how many total cards out of the deck did you have to take out before a readily observable warming trend (as seen across several 30 year periods) was clearly visible in your graph? What does this simulation tell you about what a long-term pattern of climate change might look like?
2. Based on your experience, do you think that it is possible for an individual to really experience climate change with her senses?
3. No model is perfect, and this simulation is no exception. What are some of the limits of this simulation with respect to the dynamics of real weather and climate?

4. Examine the graphs posted by several other colleagues, and compare the graphic displays.  Do some look like "climate change" is more dramatic than in others? How do your observations relate to media literacy and what we need to communicate to our learners?


5.  Do you have suggestions to refine or improve this simulation model?  Or a modification that presents a different idea related to weather and climate?

(This simulation is a modification of a classroom activity published at http://www.ucar.edu/learn/1_2_2_9t.htm)