The consensus may be moving away from global warming and towards global cooling: Scientists have been looking at different lines of evidence suggesting that the globe is in the midst of a slight cooling trend for at least the last decade or so.
Whether it’s decreasing sunspots or natural climate variations, some scientists are revisiting older theories from the 1960s and 1970s that the Earth is actually cooling off — bucking the mainstream consensus that the burning of fossil fuels is warming the planet.
Here comes the sun
One line of evidence scientists look at for clues into global cooling is sunspot activity. Low sunspot activity has historically been linked with colder periods in human history such as the period known as the “Little Ice Age” during the 1600s. Higher levels of sunspot activity have been linked to warmer periods like the one from the 1970s to the late 1990s.
Solar activity is now falling faster than any other period in the last 10,000 years, and some researchers have suggested that the planet could cool off in the coming decades.
“By looking back at certain isotopes in ice cores, [Professor Mike Lockwood of Reading University] has been able to determine how active the sun has been over thousands of years,” the BBC reports. “Following analysis of the data, Professor Lockwood believes solar activity is now falling more rapidly than at any time in the last 10,000 years.”
“When we have had periods where the sun has been quieter than usual we tend to get these much harsher winters,” Sunderland University climate scientist Dennis Wheeler told the Daily Express.
This is not necessarily a new discovery, as scientists have been pointing to rapidly falling solar activity for some time now. Last year, Russian scientists said that the world could soon plunge into another Little Ice Age.
“After the maximum of solar cycle 24, from approximately 2014 we can expect the start of deep cooling with a Little Ice Age in 2055,” wrote Habibullo Abdussamatov of the Russian Academy of Science.
The U.K.’s Lockwood also told the BBC that falling sunspot activity raises the risk of entering a new Little Ice Age “from less than 10 percent just a few years ago to 25-30 percent.”
“So the warming we saw, which lasted only from 1978 to 1998, is something that is predictable and expectable,” said Don Easterbrook, professor emeritus of geology at Western Washington University. “When the ocean changed temperatures, global cooling is almost a slam dunk. You can expect to find about 25 to 30 years yet ahead of us before it starts to warm up again. It might even be more than that.”
The United Nation’s climate bureaucracy, however, downplayed the role of solar activity in influencing the Earth’s climate. A recent study from U.K. scientists found that “neither changes in the activity of the Sun, nor its impact in blocking cosmic rays, can be a significant contributor to global warming.”