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Weather Versus Climate Explorer

Run the Weather Versus Climate Explorer MicroSim Fullscreen

About This MicroSim

This is the hardest idea in the chapter and the one most easily misunderstood in either direction.

The chart shows one station's temperature record, and the only thing that changes between views is how much of it you are looking at:

  • One week - seven daily values. The trend overlay is disabled, with the message "Seven days is not enough to see a trend. This is weather."
  • One year - the seasonal cycle dominates everything. Still disabled: "One year shows the seasons, not the climate. Come back with thirty."
  • Thirty years - monthly means. Now, and only now, a trend can be fitted.

The y-axis range is fixed across all three views. This is deliberate and it matters: the same vertical distance always means the same number of degrees, so you cannot be fooled by a rescaled axis into thinking the variation changed.

The dataset is synthetic but realistic, generated once and committed as a static JSON file, so every learner in the room is discussing the same numbers. Underneath the seasons and the day-to-day noise sits a slow warming trend of about 0.2 °C per decade. You cannot see it in a week. You cannot see it in a year. It is unmistakable in thirty.

Red points are record days. Clicking one makes the point that a single extraordinary day does not move the thirty-year average at all.

How to Use

  • Press One week, One year and Thirty years to change the window. Notice that the y-axis does not move.
  • Tick Show 30-year average line to draw the climate normal. In the thirty-year view this also draws the fitted trend line; in the shorter views it is disabled on purpose.
  • Hover any point for the date, the value, and how far it sits from the thirty-year average.
  • Click a red record day and read what happens to the average line. Nothing does.
  • Toggle the overlay on and off in the thirty-year view. The data never changes; only whether you are allowed to fit a line to it.

Iframe Embed Code

You can add this MicroSim to any web page by adding this to your HTML:

<iframe src="https://iowerx.github.io/pi-env-monitor/sims/weather-versus-climate-explorer/main.html"
        height="582px"
        width="100%"
        scrolling="no"></iframe>

Lesson Plan

Grade Level

6-12

Duration

15-20 minutes

Bloom's Taxonomy Level

Analyze (L4)

Prerequisites

  • Reading a line chart
  • Knowing what an average is
  • Understanding that seasons repeat annually

Activities

  1. Weather (4 min): Stay in the one-week view. Describe the temperature in words. Try to state a trend. Notice that the sim will not let you draw one, and say why that restriction is fair.
  2. Seasons (5 min): Switch to one year. What dominates the picture now? Is that climate or is it just the calendar?
  3. Climate (7 min): Switch to thirty years and turn the overlay on and off. Estimate the total warming across the record. Then click a record hot day and check whether it moved the average.

Assessment

  • Explains why a trend cannot be fitted to seven days.
  • Distinguishes the seasonal cycle from a long-term trend.
  • States that one extreme day is evidence of weather, not of climate.

References

  1. NOAA NCEI: U.S. Climate Normals - what a thirty-year average is and why thirty.
  2. NASA GISS Surface Temperature Analysis (GISTEMP) - the real version of the thirty-year view.
  3. IPCC Sixth Assessment Report, Working Group I - the observed warming rate this dataset imitates.
  4. Wikipedia: Climate variability and change