Board Thread:Questions and Answers/@comment-2.223.203.11-20130328203048/@comment-3412412-20130328220033

Mykdl'dy and Punk Hazard are the same, albeit Punk Hazard is a island and Mykdl'dy is a planet. Punk Hazard was half frozen and half burnt in a fight, that lasted 10 days and permantly, between two Marines (which abilities granted by items called Devil Fruits) to decide who becomes fleet admiral. Mykdl'dy was probably created the way it is or became like that after that two headed dragon arrived on the planet.

The extreme temperature differences between the ice and magma on Punk Hazard lead to an equally extreme difference in air pressure, forming massive gale-force winds. This is what is probably what is happening on Mykdl'dy that prevents the entire planet from burning.