Doraemon: Nobita and the Kingdom of Clouds 1992

Doraemon launches its ecological adventure to save Earth from a terrible threat with Nobita and his whole gang. This time Doraemon used his inventions to create, along with Nobita, his own world in the sky, a giant cloud. During their journey to the cloud are alien beings who seek to destroy civilization to chasten humans for their lack of commitment to the environment. Doraemon and the gang must find allies and convince the people of the clouds on Earth that there are people who fight for nature. In his adventure, meet good friends, raffled countless dangers, will encounter prehistoric animals and will give everything to defend our planet.