Temperature and Precipitation Variance in CMIP5 Simulations and Paleoclimate Records of the Last Millennium
AuthorParsons, Luke A.
Loope, Garrison R.
Overpeck, Jonathan T.
Ault, Toby R.
Cole, Julia E.
AffiliationUniv Arizona, Dept Geosci
Univ Arizona, Dept Hydrol & Atmospher Sci
MetadataShow full item record
PublisherAMER METEOROLOGICAL SOC
CitationTemperature and Precipitation Variance in CMIP5 Simulations and Paleoclimate Records of the Last Millennium 2017, 30 (22):8885 Journal of Climate
JournalJournal of Climate
Rights© 2017 American Meteorological Society.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractAccurate assessments of future climate impacts require realistic simulation of interannual-century-scale temperature and precipitation variability. Here, well-constrained paleoclimate data and the latest generation of Earth system model data are used to evaluate the magnitude and spatial consistency of climate variance distributions across interannual to centennial frequencies. It is found that temperature variance generally increases with time scale in patterns that are spatially consistent among models, especially over the mid-and high-latitude oceans. However, precipitation is similar to white noise across much of the globe. When Earth system model variance is compared to variance generated by simple autocorrelation, it is found that tropical temperature variability in Earth system models is difficult to distinguish from variability generated by simple autocorrelation. By contrast, both forced and unforced Earth system models produce variability distinct from a simple autoregressive process over most high-latitude oceans. This new analysis of tropical paleoclimate records suggests that low-frequency variance dominates the temperature spectrum across the tropical Pacific and Indian Oceans, but in many Earth system models, interannual variance dominates the simulated central and eastern tropical Pacific temperature spectrum, regardless of forcing. Tropical Pacific model spectra are compared to spectra from the instrumental record, but the short instrumental record likely cannot provide accurate multidecadal-centennial-scale variance estimates. In the coming decades, both forced and natural patterns of decade-century-scale variability will determine climate-related risks. Underestimating low-frequency temperature and precipitation variability may significantly alter our understanding of the projections of these climate impacts.
Note6 month embargo; published online: 17 Oct 2017
VersionFinal published version
SponsorsNational Science Foundation EaSM2 Grant [AGS-1243125]; Directorate for Geosciences ; Graduate Research Fellowship [DGE-1143953]; Kartchner Caverns scholarship fund; Department of Geosciences at the University of Arizona