Scientists claim that air pollution causes a decline in the world’s average air temperature. In order to prove that theory, ecologists have turned to historic data in relation to especially (1) ______ huge volcanic eruptions. They suspect that volcanoes influence weather changes that are similar with air pollution. (2) ______ One source of information is the affect of the eruption of (3) ______ Tambora, a volcano in Sumbawa, the Dutch East Indies, in April 1815. The largest recorded volcanic eruption, Tambora threw 150 million tons of fine ash into the stratosphere. The ash from a volcano spreads worldwide in a few clays and remain (4) ______ in the air for years. Its effect is to turn incoming solar radiation into space and however cool the earth. For example, (5) ______ records of weather in England show between April and November 1815, the average temperature has fallen 4.5F. (6) ______ During the next 24 months, England suffered one of the cold (7) ______ periods of its history. Farmer’s records from April 1815 to December 1818 indicate frost throughout the spring and summer and sharp decreases in crop and livestock markets. Since there was a time lag of several years between reason and effect, by (8) ______ the time the world agricultural commodity has deteriorated, no one realized the cause. Ecologists today warn that we face with a twofold menace. (9) ______ The ever-present possibility of volcanic eruptions, such as that of Mt. St. Helens in Washington, added to man’s pollution of the atmosphere with oil, gas, coal, and other polluting substances, may bring us increasing colder weather. (10) ______