1 In some months, the Ides is on the 15th, and in others, it is the 13th. 2  It's supposed to be on the day of the full moon. [See Roman Calendar.]. 3  March's Ides marked the beginning of the consular year: The two annually-elected Roman consuls took office on the Ides from c. 220 B.C. to 153.
In the case of Mount Pinatubo, the result was a measurable cooling of the Earthâs surface for a period of almost two years. Because they scatter and absorb incoming sunlight, aerosol particles exert a cooling effect on the Earthâs surface.The Pinatubo eruption increased aerosol optical depth in the stratosphere by a factor of 10 to 100 times normal levels measured prior to the eruption.ecause they scatter and absorb incoming sunlight, aerosol particles exert a cooling effect on the Earthâs surface. The Pinatubo eruption increased aerosol optical depth in the stratosphere by a factor of 10 to 100 times normal levels measured prior to the eruption.
The second-largest volcanic eruption of this century, and by far the largest eruption to affect a densely populated area, occurred at Mount Pinatubo in the Philippines on June 15, 1991.The eruption produced high-speed avalanches of hot ash and gas, giant mudflows, and a cloud of volcanic ash hundreds of miles across.hen even more highly gas charged magma reached Pinatubo's surface on June 15, the volcano exploded in a cataclysmic eruption that ejected more than 1 cubic mile (5 cubic kilometers) of material. The ash cloud from this climactic eruption rose 22 miles (35 kilometers) into the air.