A Comparative Study of CO₂ Emission Forecasting in the Gulf Countries Using Autoregressive Integrated Moving Average, Artificial Neural Network, and Holt-Winters Exponential Smoothing Models

Table 5

Predicted value of CO₂ emissions (metric tons per capita) using the Holt-Winters exponential smoothing model and accuracy measures.

Year	KSA	UAE	KWT	BHR	QAT	OMAN
2015	18.9619	18.3657	28.8636	22.8149	36.9647	17.7822
2016	20.3868	18.7049	28.8068	22.4036	36.5989	17.8181
2017	19.6537	17.3906	28.5948	22.6495	33.7156	18.6483
2018	21.1172	17.6846	28.5373	22.2406	33.2341	18.6652
2019	20.3454	16.4155	28.326	22.4841	30.4665	19.5143
2020	21.8477	16.6644	28.2677	22.0776	29.8692	19.5124
2021	21.0372	15.4404	28.0571	22.3187	27.2173	20.3804
2022	22.5781	15.6442	27.9982	21.9146	26.5044	20.3595
2023	21.729	14.4653	27.7883	22.1533	23.9682	21.2464
2024	23.3086	14.624	27.7287	21.7516	23.1395	21.2067
2025	22.4208	13.4902	27.5195	21.9879	20.7191	22.1125
MSE	5.300806	457.0809	129.2720698	38.3314634	496.415161	3.796661954
RMSE	2.302348	21.37945	11.36978759	6.19124086	22.2803761	1.94850249