133144 - Global mean surface temperature response to large-scale patterns of variability.pdf (5.12 MB)
Global mean surface temperature response to large‐scale patterns of variability in observations and CMIP5
journal contribution
posted on 2023-05-20, 04:17 authored by Jules KajtarJules Kajtar, Collins, M, Frankcombe, LM, England, MH, Osborn, TJ, Juniper, MGlobal mean surface temperature (GMST) fluctuates over decadal to multidecadal time scales. Patterns of internal variability are partly responsible, but the relationships can be conflated by anthropogenically forced signals. Here we adopt a physically based method of separating internal variability from forced responses to examine how trends in large‐scale patterns, specifically the Interdecadal Pacific Oscillation (IPO) and Atlantic Multidecadal Variability (AMV), influence GMST. After removing the forced responses, observed variability of GMST is close to the central estimates of Coupled Model Intercomparison Project phase 5 simulations, but models tend to underestimate IPO variability at time scales >10 years, and AMV at time scales >20 years. Correlations between GMST trends and these patterns are also underrepresented, most strongly at 10‐ and 35‐year time scales, for IPO and AMV, respectively. Strikingly, models that simulate stronger variability of IPO and AMV also exhibit stronger relationships between these patterns and GMST, predominately at the 10‐ and 35‐year time scales, respectively.
History
Publication title
Geophysical Research LettersVolume
46Issue
4Pagination
2232-2241ISSN
0094-8276Department/School
Institute for Marine and Antarctic StudiesPublisher
Amer Geophysical UnionPlace of publication
2000 Florida Ave Nw, Washington, USA, Dc, 20009Rights statement
Copyright 2019 American Geophysical UnionRepository Status
- Restricted