Analysis of the characteristics of intensity of sea waves in the Arctic Basin has been performed using the WAVEWATCH III model and results of simulations of sea ice and wind in the atmosphere with the ensemble of the CMIP5 global climate models. An assessment is made of the relative role of wind waves and swell in the total intensity of sea waves in the Arctic based on the model simulations in comparison with those obtained using reanalysis and satellite data. Estimates of possible changes in sea waves accompanying a significant decrease in the extent of sea ice in the Arctic were obtained from model simulations for the 21st century under different scenarios of anthropogenic impacts. Peculiarities of various regimes of sea waves in the Arctic Basin were revealed with an assessment of the role of wind waves, swell, their interaction, and regimes of chaotic waves like choppy waves.