The paper suggests natural solar cycles account for some global warming ASIF HASSAN/AFP/Getty

A high profile scientific journal is investigating how it came to publish a study suggesting that global warming is down to natural solar cycles. The paper was criticised by scientists for containing “very basic errors” about how Earth moves around the sun.

The study was published online on 24 June by Scientific Reports, an open access journal run by Nature Research, which also lists the prestigious Nature journal among its titles. A spokesperson told New Scientist that it is aware of concerns raised over the paper, which was authored by four academics based at Northumbria University, the University of Bradford and the University of Hull, all in the UK, plus the Nasir al-Din al-Tusi Shamakhi Astrophysical Observatory in Azerbaijan.

The authors suggest that Earth’s 1°C temperature rise over the past two centuries could largely be explained by the distance between Earth and the sun changing over time as the sun orbits around our solar system’s barycentre, its centre of mass. The phenomenon would see temperatures rise a further 3°C by 2600, they say.


Ken Rice of the University of Edinburgh, UK, criticised the paper for an “elementary” mistake about celestial mechanics. “It’s well known that the sun moves around the barycentre of the solar system due to the influence of the other solar system bodies, mainly Jupiter,” he says. “This does not mean, as the paper is claiming, that this then leads to changes in the distance between the sun and the Earth.”

“The claim that we will see warming in the coming centuries because the sun will move closer to the Earth as it moves around the solar system barycentre is very simply wrong,” adds Rice. He is urging the journal to withdraw the paper, and says it is embarrassing it was published.

Gavin Schmidt of the NASA Goddard Institute for Space Studies says the paper contains egregious errors. “The sun-Earth distance does not vary with the motion of the sun-Earth system around the barycentre of the sun-Jupiter system, nor the sun-galactic centre system or any other purely mathematical reference point,” he says. He says the journal must retract the paper if it wants to retain any credibility.

Michael Brown of Monash University in Australia lamented uncritical media coverage of the paper in Australia.

Following criticism of the paper, lead author Valentina Zharkova, of Northumbria University, described Rice as a “climate alarmist” in an online discussion.

“The close links between oscillations of solar baseline magnetic field, solar irradiance and temperature are established in our paper without any involvement of solar inertial motion,” Zharkova told New Scientist.

Scientific Reports says it has begun an “established process” to investigate the paper it has published. “This process is ongoing and we cannot comment further at this stage,” a spokesperson said.

We corrected the number of authors that worked on the study.