A tropical rainforest without rain wouldn't be much of a rainforest.
I mean, all plants need water to grow, and without it, they shrivel up and die.
So what about the ancient Hawai'ian proverb "Hahai no ka ua i ka ulula'au," which means the rain follows after the forest?
How could that be?
Well, all land plants lose water when the pores on their leaves open up during photosynthesis, and this evaporation draws more water up through their stems.
With so much rain soaking the soil in rainforests, water is nearly unlimited, and accordingly, rainforest trees can afford to move and lose more water than other plants.
All that water vapor rising from the forest feeds moisture-laden clouds while also causing convection.
Together, these effects accelerate the formation of rain, which falls to the soil and gets taken up all over again.
This cycle — absorption, evaporation, and rain, happens everywhere there are plants.
However, super-wet soil, fast-pumping trees, and hot tropical sun make the cycle so fast in the rainforest that, unlike other biomes where clouds might form in one place and rain in another, in a rainforest, all that water stays in the same region.
