No, the sun is not responsible for the recent global warming trend

What is the claim?

The claim that the sun controls the earth’s climate was recently posted in a Facebook group known for promoting climate change denial, following which it has been circulating on social media. The post included an image depicting the sun and the planets of the solar system. Pointing at a small dot, likely representing the earth, as where we live, and another arrow pointing at the sun as a whole, the post claims that the sun controls Earth's climate and suggests that it is responsible for global warming. The post has gained more than 1,000 likes and 624 shares. An archived version of the post can be accessed here.

Screenshot of the viral post. (Source: Facebook/Modified by Logically Facts)

However, the claim is misleading. The recent increase in global temperatures has been mainly caused by human activities, and the sun is not responsible for it.

What did we find?

Peter Jacobs, a climate scientist at NASA's Goddard Space Flight Center’s Office of Communication, told Logically Facts that to debunk this claim, it’s important to distinguish between the role of the sun in providing incoming energy to Earth versus whether it’s causing observed warming. 

“Human activities, principally our carbon dioxide emissions, have been responsible for the observed warming since preindustrial times,” said Jacobs.

In an explainer on the NASA website, the organization clarifies that while the sun can influence Earth's climate, it is not responsible for the recent warming trend. Subtle changes in Earth’s orbit around the Sun are accountable for the cycles of ice ages. However, NASA said the warming observed in recent decades is too rapid to be linked to changes in Earth's orbit and too extensive to be caused by solar activity. 

No upward trend in solar energy

Since 1978, the amount of solar energy reaching our planet has shown no upward trend, according to NASA. “We can monitor solar activity from the ground as well as satellites in space and see that changes in solar activity couldn’t be driving the present warming. Over the past several decades, solar activity has been slightly declining even as temperatures have rapidly warmed,” Jacobs said. 

Warming not witnessed across all atmospheric layers

The NASA explainer states that if the sun were the cause of global warming, one would anticipate warming across all atmospheric layers, from the surface to the upper atmosphere (stratosphere). However, the observed pattern is surface warming and stratospheric cooling. This supports the notion that warming is driven by a buildup of heat-trapping gases near Earth's surface rather than an increase in the sun's temperature, the NASA explainer added. 

“An increase in solar irradiance would be expected to warm not only the surface and lower atmosphere but also the upper atmosphere. By contrast, enhanced greenhouse warming would be expected to warm the surface and lower atmosphere but actually cool the upper atmosphere. And this is exactly what we observe,” said Jacobs. 

Temperature increasing despite sun’s energy decreasing

A comparison chart published by NASA shows that Earth's temperature is increasing despite the sun's energy received by Earth decreasing since 1880.

Comparison chart between temperature change and solar activity. (Source: NASA)

Other apex organizations resonate with this 

A NASA article cites the United Nations' Intergovernmental Panel on Climate Change (IPCC) to clarify that the prevailing scientific consensus is that long and short-term variations in solar activity play only a very small role in Earth’s climate. It added that human-produced greenhouse gasses contribute significantly more to warming than recent solar activity fluctuations. “It is unequivocal that humans are causing the warming. Changes in the sun's activity and volcanic eruptions are not the cause of the warming trend,’ IPCC has said.  

The United States Environmental Protection Agency stated that while natural climate variations occur over various time scales, they do not account for the observed warming since the 1950s. Rather, it is extremely likely that human activities have been the dominant cause of that warming. The agency has noted that human activities have contributed substantially to climate change.

The verdict

Experts from scientific organizations like NASA have confirmed with reliable scientific data that while the sun can influence Earth’s climate to a small extent, it cannot be held responsible for the rapid warming witnessed since preindustrial times. The increase in greenhouse gas emissions from human activities is the primary reason behind recent global warming. Therefore, we have marked this claim as misleading.