Validation of ERA5 rainfall data over the South Pacific Region: case study of Fiji Islands

IF 1.9 4区 地球科学 Q3 METEOROLOGY & ATMOSPHERIC SCIENCES Meteorology and Atmospheric Physics Pub Date : 2024-06-28 DOI:10.1007/s00703-024-01025-z
Philip Obaigwa Sagero, Arti Pratap, Royford Magiri, Victor Ongoma, Phillip Okello
{"title":"Validation of ERA5 rainfall data over the South Pacific Region: case study of Fiji Islands","authors":"Philip Obaigwa Sagero, Arti Pratap, Royford Magiri, Victor Ongoma, Phillip Okello","doi":"10.1007/s00703-024-01025-z","DOIUrl":null,"url":null,"abstract":"<p>Rainfall variability has a significant impact on hydrological cycle. Understanding rainfall variability over Fiji Islands is important for decision-making in the backdrop of global warming. Reanalysis rainfall products are commonly used to overcome observed data quality challenges especially over ungauged highland areas. However, an evaluation of reanalysed datasets is important to ensure accurate and reliable climate information generated using such datasets, especially for small Island with high variable topography like Fiji. This work aims to validate the spatiotemporal performance of European Centre for Medium-Range Weather Forecasts (ECMWF) fifth-generation reanalysis rainfall (ERA5) data against ground-based station data from 19 stations for the period 1971–2020 over Fiji Islands. Correlation coefficient and difference statistics: bias, and root mean square error, are used to assess the performance of the data. Further, common Empirical Orthogonal Function (common EOFs) analysis was used to evaluate spatiotemporal performance of ERA5 datasets. The results of the station-by-station comparison shows that interpolated ERA5 annual rainfall matches the corresponding results from rain gauges remarkably well for many stations. The correlation coefficient values range from 0.5 to 0.85, while the bias spans from a negative 282 to a positive 575, and the root mean square error (RMSE) varies between 285 and 662 mm for the annual rainfall across the study area. However, there is overestimation and underestimation of the observed rainfall by ERA5 datasets. The leading common EOF principal component for annual rainfall suggests that the inter-annual variability in ERA5 dataset is generally consistent with observed station datasets, cross validation results indicated high scores (correlations of 0.82), with limited spatial variation. This work presents a reliable data assessment of the ERA5 data over Fiji Islands, indicating there is good match of the annual observed rain gauged station data and ERA5. The findings give accuracy references for further use of the ERA5 data in understanding rainfall variability and change over the region.</p>","PeriodicalId":51132,"journal":{"name":"Meteorology and Atmospheric Physics","volume":null,"pages":null},"PeriodicalIF":1.9000,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Meteorology and Atmospheric Physics","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1007/s00703-024-01025-z","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"METEOROLOGY & ATMOSPHERIC SCIENCES","Score":null,"Total":0}
引用次数: 0

Abstract

Rainfall variability has a significant impact on hydrological cycle. Understanding rainfall variability over Fiji Islands is important for decision-making in the backdrop of global warming. Reanalysis rainfall products are commonly used to overcome observed data quality challenges especially over ungauged highland areas. However, an evaluation of reanalysed datasets is important to ensure accurate and reliable climate information generated using such datasets, especially for small Island with high variable topography like Fiji. This work aims to validate the spatiotemporal performance of European Centre for Medium-Range Weather Forecasts (ECMWF) fifth-generation reanalysis rainfall (ERA5) data against ground-based station data from 19 stations for the period 1971–2020 over Fiji Islands. Correlation coefficient and difference statistics: bias, and root mean square error, are used to assess the performance of the data. Further, common Empirical Orthogonal Function (common EOFs) analysis was used to evaluate spatiotemporal performance of ERA5 datasets. The results of the station-by-station comparison shows that interpolated ERA5 annual rainfall matches the corresponding results from rain gauges remarkably well for many stations. The correlation coefficient values range from 0.5 to 0.85, while the bias spans from a negative 282 to a positive 575, and the root mean square error (RMSE) varies between 285 and 662 mm for the annual rainfall across the study area. However, there is overestimation and underestimation of the observed rainfall by ERA5 datasets. The leading common EOF principal component for annual rainfall suggests that the inter-annual variability in ERA5 dataset is generally consistent with observed station datasets, cross validation results indicated high scores (correlations of 0.82), with limited spatial variation. This work presents a reliable data assessment of the ERA5 data over Fiji Islands, indicating there is good match of the annual observed rain gauged station data and ERA5. The findings give accuracy references for further use of the ERA5 data in understanding rainfall variability and change over the region.

Abstract Image

查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
南太平洋地区ERA5降雨量数据验证:斐济群岛案例研究
降雨量的变化对水文循环有重大影响。在全球变暖的背景下,了解斐济群岛的降雨量变化对决策非常重要。再分析降雨量产品通常用于克服观测数据质量方面的挑战,尤其是在没有测站的高原地区。然而,对再分析数据集进行评估对于确保使用此类数据集生成的气候信息准确可靠非常重要,尤其是对于像斐济这样地形多变的小岛屿。这项工作旨在验证欧洲中期天气预报中心(ECMWF)第五代再分析降雨量(ERA5)数据与斐济群岛 1971-2020 年期间 19 个地面站数据的时空性能。相关系数和差异统计:偏差和均方根误差用于评估数据的性能。此外,还使用了共同经验正交函数(共同 EOFs)分析来评估 ERA5 数据集的时空性能。逐站比较的结果表明,ERA5 插值年降雨量与许多站点雨量计的相应结果非常吻合。整个研究区域的年降雨量的相关系数从 0.5 到 0.85 不等,偏差从负 282 到正 575 不等,均方根误差(RMSE)在 285 到 662 毫米之间。然而,ERA5 数据集对观测降雨量存在高估和低估。年降雨量的主要共同 EOF 主成分表明,ERA5 数据集的年际变异性与观测站数据集基本一致,交叉验证结果显示得分较高(相关性为 0.82),空间变异有限。这项工作对斐济群岛上空的ERA5数据进行了可靠的数据评估,表明年度观测雨量站数据与ERA5数据匹配良好。研究结果为进一步利用ERA5数据了解该地区降雨量的变异和变化提供了准确的参考。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 去求助
来源期刊
Meteorology and Atmospheric Physics
Meteorology and Atmospheric Physics 地学-气象与大气科学
CiteScore
4.00
自引率
5.00%
发文量
87
审稿时长
6-12 weeks
期刊介绍: Meteorology and Atmospheric Physics accepts original research papers for publication following the recommendations of a review panel. The emphasis lies with the following topic areas: - atmospheric dynamics and general circulation; - synoptic meteorology; - weather systems in specific regions, such as the tropics, the polar caps, the oceans; - atmospheric energetics; - numerical modeling and forecasting; - physical and chemical processes in the atmosphere, including radiation, optical effects, electricity, and atmospheric turbulence and transport processes; - mathematical and statistical techniques applied to meteorological data sets Meteorology and Atmospheric Physics discusses physical and chemical processes - in both clear and cloudy atmospheres - including radiation, optical and electrical effects, precipitation and cloud microphysics.
期刊最新文献
Forecasting the El Niño southern oscillation: physics, bias correction and combined models Squall lines and turbulent exchange at the Amazon forest-atmosphere interface Synoptic patterns associated with heavy rainfall events in the metropolitan region of Porto Alegre, Brazil Ensemble characteristics of an analog ensemble (AE) system for simultaneous prediction of multiple surface meteorological variables at local scale Studying the effect of sea spray using large eddy simulations coupled with air–sea bulk flux models under strong wind conditions
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1