Abstract: Pingtan Island is located of the eastern coast of China’s Fujian Province, which is one of the typical coastal dunes in China, well-known for its typical shape, volume, and limited human disturbance. The island was severely impacted by a group of three typhoons (Nepartak, Meranti, and Megi) during summer 2016. Field investigations were conducted on the island before and after the typhoon group landed almost a year, with using high-precision RTK GPS technology and surveying methods. We analyzed morphological change of coastal climbing dunes after the typhoon group. The results indicated that: (1) The maximum height change among coastal climbing dunes was 1.43 m, and dune volume decreased slightly by 0.13%; the changes in height differed between climbing dune sites, for example, the maximum height changes at the trailing edge of climbing dunes varied because of the destruction of vegetation. (2) Coastal climbing dunes showed no cumulative effects in their responses to the typhoon group, despite an individual typhoon showing obvious impacts on coastal dune morphology. (3) The basic morphological change of coastal climbing dunes after typhoon was comprised of increases in volume and height. Especially, the front part of climbing dunes has obvious change rule. (4) In general, the morphological change of coastal climbing dunes were mainly due to the typhoon intensity and quantity, to dune type and previous morphology, vegetation density, beach type, the trend of the coastline, the surrounding environment, and so on. The morphological recovery and change of climbing dune after typhoon group are similar to its formation and development factors, among which the supplies of beach sands and wind condition play a critical role.

Key words: Pingtan Island, coastal climbing dunes, typhoon group, dune morphology