Answer:
A jet stream that alternates between hot and cool periods.
Explanation:
Winds typically travel at the very same latitudes, but Rossby waves occur when winds shift it into hurricane pattern. The Rossby waves go in a north-south direction and then return again. Whenever the Rossby waves' breezes swing up, they transport warm air first from tropical to the northern, while when they swing down, they transport cold air from either the Arctic to the south, resulting in alternating warm and cold spells.
Answer:
This is showing that the universe is growing and is possibly going to continue to grow or grow and collapse on itself creating a new universe.
Explanation:
Answer: Disease (economic disruptions) Also keep in mind that bacterica, cancer, tumors etc. were not brought up till the 1980's - 2000's
Explanation: Look at my comment because it got cencored for some reason
D. high and low levels of silica in the different type of lava.
Explanation:
The volcanoes have different types of explosions. Some tend to be highly explosive, some less explosive, some don't have explosions at all, while some have combinations of different eruptions. The reason for this diversity in the eruption types is mostly the composition of the magma, or rather how high is the silica content in it.
Basically, the higher the silica level in the magma the higher the explosiveness, and the lower the silica level the lower the chances of explosiveness. This is the case because the higher amount of silica makes the magma thicker, so the gasses are trapped and they explode, while when the lower silica content makes the magma less thick, so the gasses are not trapped and explosions are lacking.