New Insights On 'Global Warming Hiatus' Revealed In New Study

Global Mean Surface Temperatures (GMST) displayed a temporary slowdown of warming from 1998 to 2013 relative to that from 1950 to 1999. This phenomenon was concluded to be merely the energy redistribution within the oceans.

In a study published in Earth’s Future, an American Geophysical Union’s journal, new understanding on the “global warming hiatus” was discussed. Co-first authors Xiao-Hai Yan and Tim Boyer, along with scientists from different institutions, recognize that there are still gaps in knowledge as well as uncertainties regarding the phenomenon.

“NASA’s examination of ocean observations has provided its own unique contribution to our knowledge of decadal climate trends and global warming,” said co-author Veronica Nieves of UCLA, as per American Geophysical Union, “Scientists have more confidence now that Earth’s ocean has continued to warm continuously through time. But the rate of global surface warming can fluctuate due to natural variations in the climate system over periods of a decade or so.”

Yan suggested to the climate community to change terminologies from “global warming hiatus” to “global surface warming slowdown” as it is “more accurately describes the slowdown in global mean surface temperature rise in the late 20th century.”

They have reviewed existing publications regarding the hiatus and found seemingly contradicting reasons behind the redistribution: cooling in the central and eastern equatorial Pacific waters, concurrent effects of changing amplitudes of the PDO and AMO, and the movement of heat to the deeper layers of Atlantic and Southern Oceans.

In their paper The Global Warming Hiatus: Slowdown or Redistribution?, they recognized the broad agreement that the global mean surface temperature increase from 1998 to 2013 is caused by the higher heat energy transferred to the global ocean.
Complexities on how heat is redistributed, as multiple studies from their report have shown, go beyond the restrictions of GMST.

The co-first authors recommended the continuous support for Argo, the main system for monitoring ocean heat changes, to gain a more detailed understanding of heat flow into and through the oceans.