## 2 Field Measurements  
The three high-rises buildings (A, B, and C) monitored in this study are approximately 500 m from the beach, as shown in Figure 1. Three buildings have plane size approximately 60 m \(\times\) 30 m. Buildings A and B are in the northern side and face the same direction; the maximum heights are 102.9 and 110.7 m, respectively. The distance between the two buildings is 20.5 m. The height of building C is 149.8 m, as shown in Figure 2b. The terrain around the building cluster is shown in Figure 1. The coordinates of the measurement point at the origin aids in illustrating the ground roughness in each incoming flow direction. It begins from north (set as 0\({}^{\circ}\)) changing clockwise to the east (set as 90\({}^{\circ}\)). There is a city with super high-rise buildings located between 0\({}^{\circ}\) and 25\({}^{\circ}\). There is a town between 25\({}^{\circ}\) and 70\({}^{\circ}\), a sea between 70\({}^{\circ}\) and 90\({}^{\circ}\), an island at 90\({}^{\circ}\)-140\({}^{\circ}\), and an ocean at 140\({}^{\circ}\)-195\({}^{\circ}\). The terrain at an interval between each wind direction within 30 km of the measurement point is categorized into three types, namely; metropolis, open land, and ocean, as shown in Figure 1a. The measured high-rises and the surrounding environments  
Figure 1: Satellite view of the measurement point and the building monitored. (**a**) Diagram of ground roughness in different directions. (**b**) Actual measurements of the building and its surrounding environment. Figure 2: Arrangement of the R.M. Young propeller anemometers. (**a**) Installation diagram and mast. (**b**) Layout plan of the building and wind direction. are shown in Figure 1b, and several low-rise buildings and a coastal highway are located between the beach and building cluster. Six low-rise buildings are located next to the building cluster, and an open land is situated in the distance. The south contains a music school and high-rises that are barely arranged in a row, a 258 m super high-rise building is 165 m away from the northern side of high-rise A. The remaining residential areas are mainly low-rise or multi-storey buildings. The terrain around the measurement location is generally flat and open, and the experimental building is not disturbed in several incoming directions. Typhoons are monitored using three R.M. YOUNG propeller anemometers (R. M. Young Company, Michigan, US) mounted on the mast on the roof of each building. The mast is installed 4.2 m above a 3 m high fence in the east corner of the roof (Figure 2a). The height difference of the anemometers is equal to the height difference of the buildings, and the distances between two buildings are approximately 80 and 130 m. The location and wind direction of each anemometer are shown in Figure 2b. The included angle between high-rise A/B and the north direction is 39\({}^{\circ}\), and that between the long side of high-rise C and the long side of high-rise A/B is 90\({}^{\circ}\). Judging from the direction of the building and the location of the anemometer, the wind fields on the roofs of high-rises A and B are less disturbed when the northeast wind is dominant. Meanwhile, the wind field on the roof of high-rise C is less disturbed when the southeast wind is dominant. As reported by the Central Meteorological Observatory, at 2:00 PM on 10 th September, 2016 (local time), Typhoon Meranti (14 th typhoon in 2016) was generated on the Pacific Northwest. Its intensity was initially that of a tropical storm, but it rapidly increased in the next few days. On 13 th September, Typhoon Meranti turned into a super typhoon with the highest wind speed of approximately 75 m/s in the centre and landed in Xiamen at 3:15 AM on 15 th September, and the distance between the experimental building and the landing point is 10.6 km.