Chart assignment

Charts to read and discuss

Read each chart, then answer its questions. Every chart shows its source and date; open it for a table of the numbers and the data to download.

  1. Are US summers getting hotter?
  2. Are U.S. roads getting safer per mile driven?

Chart 1 of 2 · Climate

Are US summers getting hotter?

The interactive chart needs JavaScript. The numbers are on the chart's page.

Summer 2026 (June to August) averaged 74.4°F across the contiguous US. The hottest summer since records began in 1895 was 2026, at 74.4°F; 1936, the Dust Bowl summer, averaged 74.0°F. Through 2026, the dashed trend line, the straight line that best fits every summer, rose about 0.14°F a decade over the whole record, and summers had warmed about 0.46°F a decade since 1970.

Questions to discuss

  1. In one sentence of your own, what does this chart show?
  2. Find the biggest change or difference in the chart. What might explain it?
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

Source: NOAA National Centers for Environmental Information, Climate at a Glance (Public domain (U.S. government work)) · Data as of Aug 31, 2026

Open the chart and its numbers

Chart 2 of 2 · Road safety

Are U.S. roads getting safer per mile driven?

The interactive chart needs JavaScript. The numbers are on the chart's page.

In 2024 there were 1.19 deaths for every 100 million miles driven, down from 3.35 in 1980. The lowest rate was 1.08 in 2014; it jumped to 1.34 in 2020, when people drove less but deaths rose. Miles driven are the Federal Highway Administration's estimates.

How to read this chart

Each point is the number of people killed in traffic crashes for every 100 million miles Americans drove that year. Dividing by miles driven turns a count into a rate, so years when people drove more or less can be compared fairly.

Questions to discuss

  1. About what fraction of the 1980 rate is the rate in the latest year?
  2. In 2020 people drove less, but the rate went up. What could explain that?
  3. Why is deaths per mile a fairer way to compare years than the total number of deaths?

Source: NHTSA Fatality Analysis Reporting System (FARS) and FHWA Highway Statistics (table VM-2) (Public domain (U.S. government work)) · Data as of Dec 31, 2024

Open the chart and its numbers

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