Greenland is the third-largest mountain range in the world and, due to its inhospitable nature, it is one of the least-studied places on Earth. Greenland’s vast size, extreme topography and its location in the Northern Hemisphere, however, means it has a significant impact on the weather and climate of Northern Europe. It influences the air flow in the local region where it plays a major part in the production of many of the weather phenomena observed in the area, including gravity wave generation, cyclogenesis, tip jets, katabatic flows and barrier winds. The Greenland Flow Distortion experiment (GFDex) is investigating the role of Greenland in defining both local weather systems and those further downstream.