Cover lesson · Geography · Year 9 · Advanced
DCF: Data and computational thinking → Data and information literacy
Name: Class: Date:
Print: this sheet, one per pupil, plus a sheet of graph paper each for the climate graph. All 72 readings are printed on this sheet as Table 1, so no computers are needed; a calculator each is essential. If computers are available, the same table is in welsh-weather-2023.csv and the formulae are given beside each task.
Run: 4 min read Table 1 and answer the two warm-up questions · 16 min fill in the statistics table (mean, median, range, total) · 8 min the mode task, which needs rounding first · 14 min draw the climate graph for one station · 8 min write the comparison paragraph.
Collect: this sheet plus the graph paper. The answers are on the example sheet, including every mean to one decimal place, so you can mark it without a calculator of your own.
Table 1 holds real Met Office measurements for 2023 from two Welsh coastal stations and one station just over the border inland. You are going to calculate the mean, median, mode and range, draw a climate graph, and then use your own figures to explain why the inland station behaves differently from the coastal ones. Every number in your conclusion must be one you calculated.
| Month 2023 | Valley (Anglesey) temp °C | Valley rain mm | Aberporth (Ceredigion) temp °C | Aberporth rain mm | Ross-on-Wye temp °C | Ross-on-Wye rain mm |
|---|---|---|---|---|---|---|
| Jan | 9.2 | 82.0 | 8.6 | 88.0 | 8.8 | 75.2 |
| Feb | 9.7 | 23.2 | 9.3 | 17.2 | 10.8 | 7.2 |
| Mar | 9.6 | 96.6 | 9.5 | 116.6 | 10.6 | 124.2 |
| Apr | 12.4 | 36.0 | 11.9 | 40.8 | 13.5 | 62.2 |
| May | 16.6 | 27.4 | 15.0 | 20.8 | 19.1 | 33.8 |
| Jun | 21.1 | 24.4 | 20.1 | 22.6 | 23.7 | 24.6 |
| Jul | 18.6 | 112.8 | 18.3 | 84.4 | 20.7 | 63.2 |
| Aug | 18.9 | 114.2 | 18.3 | 58.0 | 21.1 | 42.4 |
| Sep | 19.7 | 134.0 | 19.2 | 93.2 | 22.1 | 48.2 |
| Oct | 15.1 | 136.2 | 14.7 | 133.4 | 16.8 | 137.0 |
| Nov | 11.5 | 75.4 | 10.8 | 108.4 | 11.4 | 80.8 |
| Dec | 10.6 | 124.0 | 10.0 | 168.4 | 10.5 | 130.6 |
Source: Met Office historic station data. Valley is on Anglesey at 10 m above sea level; Aberporth is on the Ceredigion coast; Ross-on-Wye is 60 km inland, east of the Black Mountains. "Temp" is the mean daily maximum temperature for that month.
Spreadsheet users: temperature columns are B, D and F; rainfall columns are C, E and G; the months run from row 2 to row 13.
| Statistic | Valley | Aberporth | Ross-on-Wye |
|---|---|---|---|
| Mean temperature, °C — =AVERAGE(B2:B13) | |||
| Median temperature, °C — =MEDIAN(B2:B13) | |||
| The two middle values I used | |||
| Temperature range, °C — =MAX(B2:B13)-MIN(B2:B13) | |||
| Total rainfall, mm — =SUM(C2:C13) | |||
| Mean summer temperature (Jun, Jul, Aug) | |||
| Mean winter temperature (Dec, Jan, Feb) | |||
| Summer mean minus winter mean |
Look at all 36 temperature readings. Inside any one station nothing repeats, and across the whole set only four values appear twice and nothing appears three times — so the raw data has four joint modes, which is no use to anybody. Round every reading to the nearest whole degree (9.6 becomes 10, 11.5 becomes 12), then count.
| The modal rounded temperature | |
|---|---|
| How many times does it occur? | |
| Which station and month each of those readings came from | |
| Why is the mode a weak average for temperature data? | |
| Mean of all 36 readings, and median of all 36 |
Use these prompts. Every claim needs one of your own numbers attached to it.