"Our goal was to attract the attention of the Group of Eight leaders to the problem of global warming," Hilal Atici said.
Leaders of the world's eight leading industrialized nations will gather next week in Germany for an annual summit.
"If G8 leaders fail to react promptly, it will be too late and climate change may become irreversible," she said. "We still have time to save billions of lives and human habitat from floods, draughts and natural cataclysms."
More than 20 German and Turkish carpenters use pine to make the model of the Ark, which helped Noah save people and animals from the Great Flood according to the Old Testament. The model is 33 feet long, 13 feet wide and 13 feet high. The parts of the ship were delivered to the site by a caravan of 40 horses.
The ark, which will later become a tourist site, contains over 5,000 photos of people from around the world, the Greenpeace representative said. "They all share our concern about climate change on Earth," she said.
Before the unveiling ceremony, Greenpeace activists placed a poster on the summit of Mount Ararat, more than 3,000 miles high, which called on G8 leaders to take urgent measures to save the climate on Earth.