If the earth's rotation axis was tilted by 45 degrees instead of 23.5 degrees, how would that affect the climate of the earth? would the seasons be more or less extreme? why?

Changing the tilt of the axis from 23 degrees to 45 degrees would dramatically change the seasons. They would be more extreme. Increasing the tilt angle means a larger section of the earth would experience one season for a longer period. There would be longer and colder winters and likewise hotter and longer summers. 

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