politics because politics is one of the major things
Puffapod (if this is for Harry Potter )
The answer is - because over 90% of this biome has been converted to agriculture.
This biome has been much larger before the development of the agriculture in this part of the USA, but because this biome provided large territories with deep fertile soil and predominantly lowland areas, people started using it for agriculture because it was the most suitable for that. So little by little, the biome was declining and more and more of it was becoming agricultural land.
The Southern Oscillation is in a negative phase when pressures are higher in Darwin than in Tahiti.
The Southern Oscillation Index (SOI) is a standardized index that is derived from the observed changes in sea level pressure (SLP) between Tahiti and Darwin, Australia. This index is used to predict future weather patterns. During El Nio and La Nia events, the SOI is one measurement of the large-scale fluctuations in air pressure that occur between the eastern and western tropical Pacific. These changes can be attributed to the Southern Oscillation. In general, when time series of the SOI are smoothed, a very good correlation with variations is seen in the temperatures of the oceans throughout the eastern tropical Pacific. The negative phase of the SOI indicates that the air pressure in Tahiti is lower than normal while the air pressure in Darwin is higher than normal. Extended periods of negative Southern oscillation index values coincide with ocean temperatures over the eastern tropical Pacific that are abnormally warm (cold), which is typical of El Nio (La Nia) events.
Learn more about El Nino here :
brainly.com/question/18307318
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