One of the items of information given in the Qur'an about rain is that it is sent down to Earth in due measure. This is mentioned in Sura Zukhruf as follows;

"It is He who sends down water in due measure from the sky by which We bring a dead land back to life. That is how you too will be raised (from the dead)." (The Qur'an, 43:11)

This measured quantity in rain has again been discovered by modern research. It is estimated that in one second, approximately 16 million tons of water evaporates from the Earth. This figure amounts to 513 trillion tons of water in one year. This number is equal to the amount of rain that falls on the Earth in a year. This means that water continuously circulates in a balanced cycle, in a "measure". Life on Earth depends on this water cycle. Even if people used all the available technology in the world, they would not be able to reproduce this cycle artificially.

Every year, the amount of water that evaporates and that falls back to the Earth in the form of rain is "constant": 513 trillion tons. This constant amount is declared in the Qur'an by the expression "sending down water in due measure from the sky". The constancy of this quantity is very important for the continuity of the ecological balance, and therefore, life. ago..

Even a minor deviation in this equilibrium would very soon give rise to a major ecological imbalance that would bring about the end of life on Earth. Yet, this never happens, and rain keeps falling every year in exactly the same quantity just as revealed in the Qur'an.