Study Reveals Pink Noise Offers Better View of Climate Change

New research reveals pink noise could be the key to removing natural climate variability from climate change that is impacted by human activity.

For those not aware of pink noise, it can be defined as a random noise wherein every octave has the same quantity of energy. Pink noise is found in systems ranging from electronics and earthquakes to stellar luminosity and biology. Compared to the more acquainted white noise, pink noise has more low-frequency components.

Writing in the journal Physical Review Letters, Yale researcher John Wettlaufer, graduate student Sahil Agarwal, and first author and Yale graduate Woosok Moon of Stockholm University discovered that pink noise energy signatures on decadal time scales showed up in historical climate proxy data both pre and post Industrial Revolution.

“A central question in contemporary climate science concerns the relative roles of natural climate variability and anthropogenic forcing—climate change related to human involvement—which interact in a highly nonlinear manner on multiple timescales, many of which transcend a typical human lifetime,” said Wettlaufer, the A.M. Bateman Professor of Geophysics, Mathematics and Physics at Yale.

“We find that the observed pink noise behavior is intrinsic to Earth’s climate dynamics, which suggests a range of possible implications, perhaps the most important of which are ‘resonances’ in which processes couple and amplify warming,” Wettlaufer said.