Department of Ocean Engineering and Naval Architecture, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721 302, India.
Environ Monit Assess. 2019 Aug 9;191(9):554. doi: 10.1007/s10661-019-7729-0.
A proper evaluation and performance assessment of climate model projections have received considerable attention during the recent past amongst the scientific community. Quality of wind datasets used for analysis is of paramount importance to meteorologists, oceanographers, and climatologist as an essential pre-requisite for modelling needs. This study examined the measured wind speeds obtained from satellite altimetry available from IFREMER/CERSAT, along with two atmospheric reanalysis products ECMWF ERA-Interim and NCEP-CFSR. The reanalysis products and altimeter data were compared with wind speed simulated from 33 different models under WCRP-CMIP5 project for the Bay of Bengal (BoB) region. Study investigated both historical and projections of CMIP5 data providing an opportunity to inter-compare the wind speeds resulting from various emission scenarios with Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0, and 8.5, respectively. The objective is to establish and find out a suitable emission scenario applicable to the BoB region. Temporal and spatial analyses of CMIP5 data infer variability in terms of correlation, bias, and root mean square error. For the historical runs (1991-2005) based on analysis of 29 CMIP5 models, it could be ascertained that the correlation coefficient in wind speed varied between 0.6 and 0.9 and with a bias ranging from - 1.6 to 4 ms. Similar analysis of the CMIP5 projections was carried out with 11 models for RCP 2.6, 29 models for RCP 4.5, 10 models for RCP 6.0, and 28 models for RCP 8.5. Basin-scale mean using altimeter and re-analysis products indicates that RCPs 2.6 and 6.0 showed less correlation with a higher bias for the study region. Analysis of historical model runs signifies that HadGEM2-ES, HadGEM2-AO, HadGEM2-CC, MIROC5, GISS-E2R, and CNRM-CM5 are the best performing models for the study domain. Findings from the study indicate that RCP 4.5 wind speed stands better for the Bay of Bengal region. In a broader perspective, due to various uncertainties involved in climate model outputs, it is imperative to perform a comprehensive analysis amongst multiple data sources to establish and identify the best quality data for scientific needs.
在最近的科学界中，对气候模型预测的适当评估和性能评估受到了相当大的关注。用于分析的风数据集的质量对气象学家、海洋学家和气候学家至关重要，是建模需求的必要前提。本研究检查了来自 IFREMER/CERSAT 的卫星测高可用的测量风速，以及两个大气再分析产品 ECMWF ERA-Interim 和 NCEP-CFSR。将再分析产品和测高数据与 WCRP-CMIP5 项目下为孟加拉湾（BoB）地区模拟的 33 个不同模型的风速进行了比较。该研究调查了 CMIP5 数据的历史记录和预测，为比较各种排放情景下的风速提供了机会，这些风速分别与代表性浓度途径（RCPs）2.6、4.5、6.0 和 8.5 相对应。其目的是建立并找到适用于 BoB 地区的合适排放情景。CMIP5 数据的时间和空间分析推断出相关性、偏差和均方根误差方面的可变性。对于基于 29 个 CMIP5 模型分析的历史运行（1991-2005 年），可以确定风速的相关系数在 0.6 到 0.9 之间，偏差范围在-1.6 到 4 ms 之间。对 RCP 2.6 进行了 11 个模型的类似分析，对 RCP 4.5 进行了 29 个模型的分析，对 RCP 6.0 进行了 10 个模型的分析，对 RCP 8.5 进行了 28 个模型的分析。使用测高仪和再分析产品的流域尺度平均值表明，对于研究区域，RCPs 2.6 和 6.0 的相关性较低，偏差较大。对历史模型运行的分析表明，HadGEM2-ES、HadGEM2-AO、HadGEM2-CC、MIROC5、GISS-E2R 和 CNRM-CM5 是研究域中表现最好的模型。研究结果表明，RCP 4.5 的风速更适合孟加拉湾地区。从更广泛的角度来看，由于气候模型输出存在各种不确定性，因此必须在多个数据源之间进行全面分析，以建立和确定满足科学需求的最佳质量数据。
