How hot was it? Hotter than ever!
Breaking temperature records by an entire degree is unprecedented, scientists say. Normally, records are broken by a tenth of a degree or so.
Scientists say the U.S. heat is part global warming in action and natural weather variations. The drought that struck almost two-thirds of the nation and a La Nina weather event helped push temperatures higher, along with climate change from man-made greenhouse gas emissions, said Katharine Hayhoe, director of the Climate Science Center at Texas Tech University. She said temperature increases are happening faster than scientists predicted.
Global warming is caused by the burning of fossil fuels — coal, oil and natural gas — which sends heat-trapping gases, such as carbon dioxide, into the air, changing the climate, scientists say.
Last year was by far the hottest year on record in the United States. Here's 2012's heat by the numbers:
- Average annual temperature: 55.32 degrees F, a record. The old record was 54.32 degrees, set in 1998.
- Weather stations across the Lower 48 states setting all-time high temperatures: 356.
- Weather stations setting all-time low temperatures: Four.
- Number of states that had their warmest year: 19.
- Months in 2012 that set U.S. heat records: March and July.
- Number of people who experienced at least 10 days of 100-degree heat: 99.1 million.
- Number of consecutive months that the United States had warmer than average temperatures: 16.
- New all-time warmest temperature in South Carolina: 113 degrees.
Critical thinking challenge: Why does one degree of temperature mean so much? What is the difference between 32 degrees and 33 degrees?
Define this word: unprecedented
- Posted on January 9, 2013