Areas near the volcano will undoubtedly be subject to inundation by mudflows for several more years. The Effects of the 1991 Eruption Plate tectonics around Pinatubo As you can see from the map , the Phillipine Plate is colliding with the Eurasia Plate. This causes pressure in the mantel that must be released in the form of earthquakes and volcanoes. In the case of the Phillipines, the pressure was released by the explosion of Mt. Pinatubo. When the pressure builds up again, Mt Pinatubo might erupt again sometime in the future.
Volcanic eruptions are responsible for the global cooling.
When the volcanoes erupt, they blast huge clouds of particles and gases, including sulfur dioxide into the atmosphere. Millions of tons of sulfur dioxide gas can reach the stratosphere from a major volcano. These sulfate particles reflect energy coming from the sun, thereby preventing the sun's ray from heating the Earth. Global cooling often has been linked with major volcanic eruptions. The June 1991 eruptions of Pinatubo is an example.