The nautical decors of your room can be transformed to add certain items which can add warmth to your room. The colors and accessories you use for the room can change the cold atmosphere of the nautical room into a bit warmer one. Use dark colors for items like your blanket, towels, curtains, etc. A color like brown which indicates sand can make the room warmer and cozier during the winters.
Use a transparent vase filled with sand and attractive branches; place it at the table or on some furniture in the room. Deep blue is the color you should go for instead of light blue for your nautical room. The pillows and bed-sheets are the ones to which you can use the deep blue coloration. Golden yellow, dark red and shades of orange are some of the colors which enhance the warmth of the room and give depth to the space.