Think about this for more than a second or two.
This is taken from my lessons in the Chumash.
According to the Baal Shem Tov Miriam, Moshe, and Aaron each had responsibilities for the water, food, and protection for us Jews in the 40 year journey in the desert to the Promised Land.
Miriam had the blessing of the water. Where ever we Jews went in the desert the roiling water well followed us.
Moshe had blessing of the Mana.
Aaron had the blessing of the pillar of cloud. This cloud gave us protecting from the enemy as well as the perfect temperatures of day to protect us from the heat of the day as well as the heat to keep us warm in cold desert night.