41. The amount of sulfur dioxide is comparable to the 20 million tonnes of the 1991 eruption of Mount Pinatubo . 42. The eruption of Mount Pinatubo on June 14, 1991 caused much havoc to Guagua and its neighboring municipalities. 43. Much of the damage in Luzon centered around the provinces surrounding Mount Pinatubo , a volcano which erupted in 1991. 44. Clark was closed by U . S . authorities because of extensive damage during the 1991 eruption of Mount Pinatubo . 45. The haze was particularly bad in 1991, when the eruption of Mount Pinatubo added extra ash to the atmosphere. 46. Troops were searching Mount Pinatubo for Navy Lt . Scott Alan Washburn of Celina, Ohio, by ground overnight. 47. The 1991 eruption of Mount Pinatubo is the world's second-largest terrestrial eruption of the 20th century. 48. Notable lahars include those at Mount Pinatubo and Nevado del Ruiz, the latter of which killed thousands of people. 49. Mount Pinatubo and the other volcanoes on this volcanic belt arise due to magma occlusion from this subduction plate boundary.50. She assisted in Operation Fiery Vigil, the evacuation of civilians from the Philippines during the eruption of Mount Pinatubo .
