Glaciers affect global circulation by cooling
the air around them. Two major physical systems
cause our weather:
1-- Our planet spins as we orbit the sun which
causes the air masses to move and
2-- Warmer air masses rise while cooler air masses
Air at the equator is usually much warmer
because it is being heated by the direct sun rays.
Air at our poles is much cooler. The
temperature of the air masses changes how they
move and mix.
Glaciers are very cold so they cool the air that
flows over them. Sometimes very large glaciers
even have their own regulated miniature weather
Without the glaciers cooling the air around them,
the air currents in that area would change.