Interpret several independent lines of data, temperature records, atmospheric carbon dioxide, ice and sea level, as evidence used to describe recent climate trends.
Scientists do not rely on just one measurement to describe how Earth's climate is changing; they look for agreement across several independent kinds of evidence. Thermometer records kept at weather stations around the world for over a century show global average temperature trending upward. Separately, air samples measured continuously atop a Hawaiian volcano since 1958 show atmospheric carbon dioxide steadily rising year after year, a record called the Keeling Curve.
Other independent evidence points the same direction: satellite and ground measurements show many glaciers and areas of Arctic sea ice have shrunk over recent decades, and tide gauges and satellites both show global average sea level slowly rising, partly from melting ice and partly from ocean water expanding as it warms. Reading evidence matter-of-factly means describing exactly what each data set shows without exaggerating or minimizing it, and noticing when several independent measurements point in the same direction.
Mastery looks like: They can name at least three independent lines of evidence used to describe a warming trend and explain why agreement across independent measurements strengthens a conclusion.
Common stumbles: Treating a single data point or single year as proof either way; confusing describing the evidence with arguing a policy opinion.