Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea

Extended-range forecasts beyond short-term period provide valuable meteorological insights, supporting decision-making across diverse sectors. However, their practical utility is often limited by the inherent uncertainties in initial conditions and model errors, emphasizing the need for thorough eva...

Full description

Saved in:
Bibliographic Details
Main Authors: Subin Ha, Quan J Wang, Jina Hur, Eun-Soon Im
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:Environmental Research Communications
Subjects:
Online Access:https://doi.org/10.1088/2515-7620/adcdcf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850172129702576128
author Subin Ha
Quan J Wang
Jina Hur
Eun-Soon Im
author_facet Subin Ha
Quan J Wang
Jina Hur
Eun-Soon Im
author_sort Subin Ha
collection DOAJ
description Extended-range forecasts beyond short-term period provide valuable meteorological insights, supporting decision-making across diverse sectors. However, their practical utility is often limited by the inherent uncertainties in initial conditions and model errors, emphasizing the need for thorough evaluation to ensure their effective application. Among various long-range forecast models, the NCEP Climate Forecast System version 2 (CFSv2) stands out with its 6 h initialization intervals and 9-month prediction range, providing a valuable resource for assessing forecast skill across different lead times. In this light, this study assesses the 1-month CFSv2 forecast skill over South Korea, focusing on the impact of varying lead times on predictability of interannual variability of temperature and precipitation. For the summer season from 2011 to 2023, temperature and precipitation on monthly and daily scales from CFSv2 forecasts for each month, with lead times ranging from 6 h to 240 h, were compared with observed values in terms of anomaly correlation coefficients (ACCs). With regard to monthly ACCs, no significant patterns were observed for both temperature and precipitation. On the other hand, daily temperature ACCs revealed that forecasts with shorter lead times exhibited relatively better skill in predicting temperature. Meanwhile, daily precipitation anomalies from the forecasts still displayed very weak correlations with the observed anomalies across all initialization times, highlighting the limitation of forecasts in precipitation. Ultimately, this study aims to enhance our understanding of CFSv2 forecast performance in relation to varying initialization times and serve as a useful basis for more effective utilization of the forecasts in conjunction with advanced approaches such as building a time-lagged ensemble.
format Article
id doaj-art-488540409cdf4af3b48ea2b3d8b43bff
institution OA Journals
issn 2515-7620
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series Environmental Research Communications
spelling doaj-art-488540409cdf4af3b48ea2b3d8b43bff2025-08-20T02:20:09ZengIOP PublishingEnvironmental Research Communications2515-76202025-01-017404101310.1088/2515-7620/adcdcfEvaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South KoreaSubin Ha0https://orcid.org/0000-0002-8569-953XQuan J Wang1Jina Hur2Eun-Soon Im3https://orcid.org/0000-0002-8953-7538Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology , Hong Kong Special Administrative Region of ChinaDepartment of Infrastructure Engineering, Faculty of Engineering and Information Technology, The University of Melbourne , Parkville, VIC, AustraliaNational Institute of Agricultural Sciences, Rural Development Administration, Wanju-gun, Republic of KoreaDepartment of Civil and Environmental Engineering, The Hong Kong University of Science and Technology , Hong Kong Special Administrative Region of China; Division of Environment and Sustainability, The Hong Kong University of Science and Technology , Hong Kong Special Administrative Region of ChinaExtended-range forecasts beyond short-term period provide valuable meteorological insights, supporting decision-making across diverse sectors. However, their practical utility is often limited by the inherent uncertainties in initial conditions and model errors, emphasizing the need for thorough evaluation to ensure their effective application. Among various long-range forecast models, the NCEP Climate Forecast System version 2 (CFSv2) stands out with its 6 h initialization intervals and 9-month prediction range, providing a valuable resource for assessing forecast skill across different lead times. In this light, this study assesses the 1-month CFSv2 forecast skill over South Korea, focusing on the impact of varying lead times on predictability of interannual variability of temperature and precipitation. For the summer season from 2011 to 2023, temperature and precipitation on monthly and daily scales from CFSv2 forecasts for each month, with lead times ranging from 6 h to 240 h, were compared with observed values in terms of anomaly correlation coefficients (ACCs). With regard to monthly ACCs, no significant patterns were observed for both temperature and precipitation. On the other hand, daily temperature ACCs revealed that forecasts with shorter lead times exhibited relatively better skill in predicting temperature. Meanwhile, daily precipitation anomalies from the forecasts still displayed very weak correlations with the observed anomalies across all initialization times, highlighting the limitation of forecasts in precipitation. Ultimately, this study aims to enhance our understanding of CFSv2 forecast performance in relation to varying initialization times and serve as a useful basis for more effective utilization of the forecasts in conjunction with advanced approaches such as building a time-lagged ensemble.https://doi.org/10.1088/2515-7620/adcdcfCFSv21-month forecastsinterannual variability
spellingShingle Subin Ha
Quan J Wang
Jina Hur
Eun-Soon Im
Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
Environmental Research Communications
CFSv2
1-month forecasts
interannual variability
title Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
title_full Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
title_fullStr Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
title_full_unstemmed Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
title_short Evaluating interannual variability in 1-month CFSv2 forecasts with different lead times at monthly and daily scales in South Korea
title_sort evaluating interannual variability in 1 month cfsv2 forecasts with different lead times at monthly and daily scales in south korea
topic CFSv2
1-month forecasts
interannual variability
url https://doi.org/10.1088/2515-7620/adcdcf
work_keys_str_mv AT subinha evaluatinginterannualvariabilityin1monthcfsv2forecastswithdifferentleadtimesatmonthlyanddailyscalesinsouthkorea
AT quanjwang evaluatinginterannualvariabilityin1monthcfsv2forecastswithdifferentleadtimesatmonthlyanddailyscalesinsouthkorea
AT jinahur evaluatinginterannualvariabilityin1monthcfsv2forecastswithdifferentleadtimesatmonthlyanddailyscalesinsouthkorea
AT eunsoonim evaluatinginterannualvariabilityin1monthcfsv2forecastswithdifferentleadtimesatmonthlyanddailyscalesinsouthkorea