Autocorrelation—A Simple Diagnostic for Tropical Precipitation Variability in Global Kilometer-Scale Climate Models
- Autor(en)
- Dorian Spät, Michela Biasutti, David Schuhbauer, Aiko Voigt
- Abstrakt
We propose the lag-1 autocorrelation of daily precipitation as a simple diagnostic of tropical precipitation variability in climate models. This metric generally has a relatively uniform distribution of positive values across the tropics. However, selected land regions are characterized by exceptionally low autocorrelation values. Low values correspond to the dominance of high frequency variance in precipitation, and specifically of high frequency convectively coupled equatorial waves. Consistent with previous work, we show that CMIP6 climate models overestimate the autocorrelation. Global kilometer-scale models capture the observed autocorrelation when deep convection is explicitly simulated. When a deep convection parameterization is used, though, the autocorrelation increases over land and ocean, suggesting that land surface-atmosphere interactions are not responsible for the changes in autocorrelation. Furthermore, the metric also tracks the accuracy of the representation of the relative importance of high frequency and low frequency convectively coupled equatorial waves in the models.
- Organisation(en)
- Institut für Meteorologie und Geophysik
- Externe Organisation(en)
- Lamont-Doherty Earth Observatory, Universität Wien
- Journal
- Geophysical Research Letters
- Band
- 51
- ISSN
- 0094-8276
- DOI
- https://doi.org/10.1029/2024GL108856
- Publikationsdatum
- 09-2024
- Peer-reviewed
- Ja
- ÖFOS 2012
- 105204 Klimatologie
- Schlagwörter
- ASJC Scopus Sachgebiete
- Geophysics, Allgemeine Erdkunde und Planetologie
- Sustainable Development Goals
- SDG 13 – Maßnahmen zum Klimaschutz
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/a6fd2c86-fe9f-42c6-988c-b77381b53c0c