A recent study determined that global warming can trigger even further changes in the climate.

Researchers confirmed the existence of "positive feedback," in which warming itself can intensify atmospheric greenhouse gases, triggering additional warming, the University of Exeter reported.

The research team was able to directly confirm that global temperature has an impact on greenhouse gas concentrations by looking ice-core data. This suggests that as the global temperature rises, the positive feedback system is exacerbated. Researchers had already determined warmer climate periods also come with higher concentrations of greenhouse gas, but were not sure if there was a direct cause-and-effect relationship between the two factors.

"A fundamental insight by George Sugihara from the USA on how one can use observed dynamics in time series to infer causality caused a big splash in the field," explains Egbert van Nes. "It immediately made us wonder whether it could be used to solve the enigma of the iconic correlated temperature and gas history of the Earth."

The researcher turned to a "novel mathematical insight" that allowed them to look at the ice core data with fresh eyes. The analysis revealed a strong link between the Earths's glacial cycles and internal feedbacks. The findings demonstrate that observed dynamics in times series' could be used to infer causality. The researchers wonder if this method could be used to solve other climate mysteries, such as the correlation between temperature and gas history.

"It can be highly misleading to use simple correlation to infer causality in complex systems," said George Sugihara from Scripps Institution of Oceanography . "Correlations can come and go as mirages, and cause and effect can go both ways as in a kind of chicken and egg problem, and this requires a fundamentally different way to look at the data."

The findings were published in a recent edition of the journal Nature Climate Change.