On the Possible Interaction between Internal Climate Variability and Forced Climate Change

TitleOn the Possible Interaction between Internal Climate Variability and Forced Climate Change
Publication TypeJournal Article
Year of Publication2014
JournalGeophysical Research Letters
Volume41
Number8
Pages2962–2970
Date Published04/2014
Abstract / Summary

The global warming hiatus does not necessarily mean a hiatus in anthropogenic greenhouse gas forcing and forced climate change (FCC). Here we show that both Atlantic Multidecadal Variability (AMV) and Pacific Decadal Oscillation (PDO) may cause fluctuations of the global mean surface air temperature (SAT) and hence alternately positive and negative trends on (inter)decadal time scales. However, the forced SAT change under a mean state due to greenhouse gas forcing does not depend on different phases of AMV and PDO, implying the effect of the FCC and internally generated climate variability can be linearly added up to the observed transient global mean SAT. On the other hand, the regional patterns of transient FCC do depend on the phases of the internal variability since the atmospheric and oceanic circulations can be affected by the different phases of the internal variability. Our results suggest a two-way interaction between internal variability and spatial patterns of FCC.

DOI10.1002/2014GL059908
Journal: Geophysical Research Letters
Year of Publication: 2014
Volume: 41
Number: 8
Pages: 2962–2970
Date Published: 04/2014

The global warming hiatus does not necessarily mean a hiatus in anthropogenic greenhouse gas forcing and forced climate change (FCC). Here we show that both Atlantic Multidecadal Variability (AMV) and Pacific Decadal Oscillation (PDO) may cause fluctuations of the global mean surface air temperature (SAT) and hence alternately positive and negative trends on (inter)decadal time scales. However, the forced SAT change under a mean state due to greenhouse gas forcing does not depend on different phases of AMV and PDO, implying the effect of the FCC and internally generated climate variability can be linearly added up to the observed transient global mean SAT. On the other hand, the regional patterns of transient FCC do depend on the phases of the internal variability since the atmospheric and oceanic circulations can be affected by the different phases of the internal variability. Our results suggest a two-way interaction between internal variability and spatial patterns of FCC.

DOI: 10.1002/2014GL059908
Citation:
Lu, J, A Hu, and Z Zeng.  2014.  "On the Possible Interaction between Internal Climate Variability and Forced Climate Change."  Geophysical Research Letters 41(8): 2962–2970.  https://doi.org/10.1002/2014GL059908.