ENVIRONMENT

This year is on track to be one of the hottest, if not the hottest, year on record, a U.N. agency has reported. (CNN)

Use this activity to learn more about “Earth’s Changing Climates.”

Teachers, scroll down for a short list of key resources in our “Teachers’ Toolkit.”

In this 26-second video, a color-coded map displays a progression of changing global surface temperatures anomalies from 1880 through 2013. Higher-than-normal temperatures are shown in red and lower-than-normal temperatures are shown in blue.

Discussion Ideas

• The CNN article, and the World Meteorological Organization statement it describes, say that 2014 is on track to be the hottest year on record. What does “on record” mean? Why not just say “the hottest year in Earth’s history”?
  • “On record” means officially measured and noted. “Recorded history” usually refers to events that could be recorded—after people developed writing systems.
  • Earth has definitely endured hotter years than 2014. About four billion years ago, for instance, the Earth was still a partly-molten planet—even the rocks were melting. No one was around to record the temperature, however, so the Hadean Eon is known as a prehistoric time period.

• Work through the questions in our terrific activity, “Earth’s Changing Climates” to get familiar with climate change concepts. Adapt the questions to reflect the World Meteorological Organization statement.
  • What are some examples of climates? (Some commonly known climates are desert, rain forest, tropical monsoon, tropical savanna, humid subtropical, humid continental, oceanic, subarctic, and tundra.)
  • What factors determine a region’s climate? (Climate determining factors are location—next to an ocean or near the equator, for example—precipitation, and temperature.)
  • Has Earth always had the same climates as it has today? (No. Earth has gone through many climatic shifts in its history, including ice ages and warm periods.)
  • When are scientists most confident in their predictions? (Scientists are most confident in their predictions when they have a lot of data. This is why the forecast for near-term events is better than forecasts of longer-term events, both in storm forecasting and in climate forecasting.)
    • This is probably why the WMO scientists are only releasing a “provisional statement” and not an authoritative report about climate changes in 2014. The year isn’t even over, and data have not been analyzed and contextualized yet. The statement is an educated prediction, not a statement of fact.

• “Earth’s Changing Climates” uses this interactive activity, which helps users track changes in Earth’s prehistoric and historic climates. Using information from the interactive, work through these questions from the activity.
  • How do historic and prehistoric changes compare to the time scale for the most recent (current) warming trend? (The current warming appears to be happening much faster.)
  • Why do you think scientists think the warming of the 20th century cannot be explained by the natural variability seen over geologic time? (The warming is happening quickly, and it is occurring in synchrony with increased levels of carbon dioxide.)

• It’s not all gloom and doom. Read through the summary World Meteorological Organization’s statement. (The summary is the top part of the statement, above “Highlights.”) How do scientists at the WMO think global citizens are helping combat global warming?
  • Supporting political change, such as binding international agreements on carbon emissions. “Our climate is changing . . . Fortunately our political climate is changing, too, with evidence that governments, supported by investors, business, and cities, are moving towards a meaningful, universal climate agreement in Paris 2015—an agreement that keeps a global temperature rise below 2 degrees C by putting in place the pathways to a deep de-carbonisation of the world’s economy and climate neutrality or ‘net zero’ in the second half of the century,” says one scientist.

TEACHERS’ TOOLKIT

CNN: 2014 may be the hottest year on record

World Meteorological Organization: 2014 on course to be one of hottest, possibly hottest, on record; Exceptional heat and flooding in many parts of the world

Nat Geo: Earth’s Changing Climates

Concord Consortium and Nat Geo, with funding from the National Science Foundation: Earth’s Changing Climates