FALSE: WE ARE NOT HEADING INTO ANOTHER ICE AGE
Written by Odhiambo Shem on November 18, 2022
A twitter post claiming that we are heading into another ice age is false.
“We are heading into another ice age! You will likely die in an old refrigerator that someone didn’t take the door off of!” states the claim.
Just a few centuries ago, the planet experienced a mild ice age, quaintly dubbed the Little Ice Age. Part of the Little Ice Age coincided with a period of low solar activity termed the Maunder Minimum (named after astronomer Edward Maunder). It’s believed that a combination of lower solar output and high volcanic activity were major contributors (Free 1999, Crowley 2001), with changes in ocean circulation also having an effect on European temperatures (Mann 2002).
Solar activity is currently showing a long-term cooling trend. 2009 saw solar output at its lowest level in over a century. However, predicting future solar activity is problematic. The transition from a period of ‘grand maxima’ (the situation in the latter 20th century) to a ‘grand minima’ (Maunder Minimum conditions) is a chaotic process and difficult to predict (Usoskin 2007).
Simulations of the climate response if the sun did fall to Maunder Minimum levels find that the decrease in temperature from the sun is minimal compared to the warming from man-made greenhouse gases (Feulner 2010). Cooling from the lowered solar output is estimated at around 0.1°C (with a maximum possible value of 0.3°C) while the greenhouse gas warming will be around 3.7°C to 4.5°C, depending on how much CO2 we emit throughout the 21st century.
Source: Skeptical Science
Global temperatures were indeed decreasing slightly in the 1950s and 1960s, from a relative peak in the early 1940s. The main cause of the cooling was sunlight being blocked out from reaching the surface of the Earth, as a result of the rapid industrialization following the Second World War and the associated rise in air pollution. Another factor was the onset of a negative phase of the Interdecadal Pacific Oscillation that results in the oceans soaking up more heat than normal and the atmosphere missing out a little.
Some scientists did wonder if the mid-century cooling was a sign of the next ice age on the way, but even back then they were distinctly in the minority. There were a couple of high-profile media reports on the possibility of a coming ice age, but the vast majority of scientific papers even then were concerned with warming, from greenhouse gas increase.
Since the 1970s, human emissions of carbon dioxide and other greenhouse gases has grown exponentially. Since the industrial revolution began in the mid-1700s, atmospheric carbon dioxide concentrations have gone up by 120 parts per million, a 46% rise in nearly 300 years.
But half the increase has occurred in the past 30 years, and the total amount of global emissions in the century from 1750 to 1850 is what we now put into the air every six weeks. The rate of warming has increased in recent decades, in line with the much more rapid rise in atmospheric greenhouse gases in recent decades.
We looked into this claim that we are heading into another ice age and found it to be false.
This fact-check was produced by Sky 106.1 FM with support from Code for Africa’s PesaCheck, International Fact-Checking Network, and African Fact Checking Alliance network.
