Evaluation of historical precipitation interannual variability in CMIP6 over the United States

Bibliographic Details
Title: Evaluation of historical precipitation interannual variability in CMIP6 over the United States
Authors: Ryan D Harp, Thierry N Taguela, Akintomide A Akinsanola, Daniel E Horton
Source: Environmental Research: Climate, Vol 3, Iss 4, p 045032 (2025)
Publisher Information: IOP Publishing, 2025.
Publication Year: 2025
Collection: LCC:Meteorology. Climatology
LCC:Environmental sciences
Subject Terms: United States, precipitation, interannual variability, CMIP6 models, internal variability, Meteorology. Climatology, QC851-999, Environmental sciences, GE1-350
More Details: Interannual precipitation variability profoundly influences society via its effects on agriculture, water resources, infrastructure, and disaster risks. In this study, we use daily in situ precipitation observations from the global historical climatology network-daily (GHCN-D) to assess the ability of 21 Coupled Model Intercomparison Project Phase 6 (CMIP6) models, including the 50-member fifth-generation Canadian Earth System Model single model initial-condition large ensemble (CanESM5_SMILE), to realistically simulate historical interannual precipitation variability trends within 17 regions of the contiguous United States (CONUS). We assess how accurately the CMIP6 simulations align with observational data across annual, summer, and winter periods, focusing on four key hydrometeorological metrics, including interannual precipitation variability, relative interannual precipitation variability (coefficient of variation), annual mean precipitation, and annual wet day frequency. Our findings reveal that CMIP6 ensemble members generally reproduce the spatial patterns of observed trends in annual mean precipitation. In most regions, models agree well with the signs of observed changes in annual mean precipitation, though discrepancies in trend magnitude are evident. Further, observed trends in winter mean precipitation broadly exhibit a spatial pattern similar to that of the observed annual mean. However, analysis of the CanESM5_SMILE shows that trends in precipitation variability may primarily be the result of model-simulated internal variability, suggesting caution in interpreting multi-model single-realization ensemble results. Challenges in accurately simulating interannual precipitation variability underscore the need for ongoing model refinement and validation to enhance climate projections, especially in regions vulnerable to extreme precipitation events.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2752-5295
Relation: https://doaj.org/toc/2752-5295
DOI: 10.1088/2752-5295/ada17c
Access URL: https://doaj.org/article/4f9776b821e64189b6c523a77a372e51
Accession Number: edsdoj.4f9776b821e64189b6c523a77a372e51
Database: Directory of Open Access Journals
More Details
ISSN:27525295
DOI:10.1088/2752-5295/ada17c
Published in:Environmental Research: Climate
Language:English