When was the strongest El Niño event in history?

1997

The 1997–98 El Niño event was regarded as one of the strongest El Niño events in recorded history, which resulted in widespread drought, flooding and other natural disasters occurring across the globe.

Explanation:

the answer to the question is 1997-98

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

it's unlikely a majority of a large population would agree on issues

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