how does such a volcano affect climate?
Slightly cooler-than-usual temperatures were recorded worldwide, with brilliant sunsets and intense sunrises attributed to the particulates.
Stratovolcano
 the impact of the June 1991 eruption of Mount Pinatubo was global. Slightly cooler-than-usual temperatures were recorded worldwide, with brilliant sunsets and intense sunrises attributed to the particulates; this eruption lofted particles high into the stratosphere. The aerosols that formed from the sulfur dioxide (SO), carbon dioxide (CO), and other gases dispersed around the world. The SO mass in this cloud—about 22 million tons—combined with water (both of volcanic and atmospheric origin) formed droplets of sulfuric acid, blocking a portion of the sunlight from reaching the troposphere and ground. 
what is goat rocks? It is an extinct stratovolcano in the Cascade Range. name a few peaks in its vicinity? Gilbert Peak what kind of resources can be found over there? Cobalt, copper, lead, molybdenum, nickel, and zinc, and more. what does stratovolcano mean? It is a conical volcano built up by many layers (strata) of hardened lava, tephra, pumice and ash.
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Stratovolcano [SEP] Effects on climate and atmosphere
The cooling in some regions is thought to have been as much as 0.5 °C (0.9 °F). An eruption the size of Mount Pinatubo tends to affect the weather for a few years; the material injected into the stratosphere gradually drops into the troposphere, where it is washed away by rain and cloud precipitation. A similar, but extraordinarily more powerful phenomenon occurred in the cataclysmic April 1815 eruption of Mount Tambora on Sumbawa island in Indonesia. The Mount Tambora eruption is recognized as the most powerful eruption in recorded history. Its eruption cloud lowered global temperatures by as much as 3.5 °C (6.3 °F).