Atmospheric gasses that absorb infrared radiation
Colliding boundaries are convergent so the boundary would be convergent.
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Iraq had been severely bombed over periods of time<span />
Be more specific, in order to answer this question.
The Ice Ages shaped and sculpted the face of the Earth. Continents that were once connected by land bridges had shifted and separated during the Ice Ages. Therefore without the Ice Ages, Earth would look significantly different, and some of the natural beauties like Niagra Falls would not exist.