Inland waters, such as lakes and reservoirs, have been recognized as hot spots for carbon emissions in recent years, in which the diffuse release of greenhouse gases (GHGs), such as carbon dioxide (CO₂) and methane (CH₄), occurring at the air-water interface, is the primary pathway of carbon emissions. The water-air gas exchange coefficient (KL) is the key factor to calculate the fluxes of GHGs diffusion. The wind speed is usually regarded as the key driver of turbulence at the water surface of lakes and reservoirs, and is also the main factor determining the value ofKL. Most of the quantitative relationships between GHGsKL and wind speed are established based on field observation data of tracer gases such as sulfur hexafluoride (SF₆), which may be disturbed by other factors. However, there is still a lack of experimental research on the influence of wind speed on the GHGsKL, such as CO₂ and CH₄, which leads to uncertainty in the quantitative assessment of the GHGs diffuse release. The experiment of investigating the CO₂ and CH₄ concentrations changes and diffusion pattern in water under different wind speeds was conducted. The results show that the values of k₆₀₀ for CO₂ and CH₄ (i.e.,KL at a Schmidt number of 600) increase with increasing wind speed since the wind will enhance turbulence on the water surface. Additionally, wind-generated surface waves can increase the gas-liquid contact area, thereby promoting water-air interface exchange. Comparing the k₆₀₀ of CO₂ and CH₄ under the same wind speed, it is found that the average k₆₀₀ value of CH4 is about 1.29 times that of CO₂. It indicates that in addition to differences in molecular diffusion, factors such as microbubble transport flux caused by varying gas solubility also affect the water-air interface exchange. Furthermore, the differences in water-air interface exchange among gases are influenced by water turbulence. Based on the experimental results, the formulae for k₆₀₀ of CO₂ and CH₄ under different wind speeds was established. A comparison of flux calculation using measured CO₂ and CH₄ concentration data from Chinas Three Gorges Reservoir with the empirical formulae for GHGs k₆₀₀ in freshwater reservoirs recommended by the International Hydropower Association (IHA) was conducted. The results indicate that the flux calculations obtained from different formulae show a good trend of consistency, the CO₂ and CH₄ fluxes calculated in this study are 0.55 times and 0.72 times the mean values of the fluxes calculated using the recommended formula, respectively. It is suggested to adopt the results from multiple calculation formulae for comparative analysis to reduce the resulting bias caused by the artificial selection of different formulae. This study provides key insights into the patterns and mechanisms of greenhouse gas exchange across the water-air interface in aquatic systems. These findings will inform more accurate assessment models for carbon emissions from lakes and reservoirs.