A: Flowering of onions can be caused by several things, usually temperature fluctuation. An onion is classed as a biennial which means it usually takes two years to go from seed to seed. However, this condition is triggered by temperatures.
Under what conditions will the front of a glacier remain stationary? Glacial fronts remain stationary when melting and snow accumulation are equal. Glacial fronts remain stationary when friction exceeds gravity forces. Glacial fronts remain stationary when melting and snow accumulation are unequal. Glacial fronts remain stationary when gravity forces exceed friction.
This retreat and advance refers only to the position of the terminus, or snout, of the glacier. Even as it retreats, the glacier still deforms and moves downslope, like a conveyor belt. For most glaciers, retreating and advancing are very slow occurrences, requiring years or decades to have a significant effect.