Fr. Daniel J. McNamara, S.J.
September 1, 2015
Let me tell you about something so common you will wonder why I bother to talk about it. It is so common we of course take it for granted. But it is the basis of the current discussion about the environment. Especially the environment as something that is changing for the worse; the famous Climate Change issue. So do I mean carbon dioxide? No, more common than even that. In fact it is worse than carbon dioxide in this debate about what is causing the climate to change. It is water vapor.
Yes the stuff in the air that makes us say, “Why is it so hot today?” We are feeling the moisture in the air holding in the heat from our bodies, the same way it holds in the heat from the earth as it tries to escape into space. This same water vapor forms the clouds in the troposphere many of which are responsible for holding in the heat of our planet.
But the story of water vapor is actually more comprehensive than just that. Water in all its forms is first of all limited in supply. There is only so much water on the planet and it is not renewable. What we have, we have. It is recycled in the ordinary course of the processes of the living planet. The water you drink today from the water fountain may contain exactly the same water molecules drunk by Napoleon on the isle of Elba during this 19th century exile.
Secondly water is known to go through cycles. It falls from the clouds where it is formed from vapor by processes we do not totally understand. It is absorbed by the planet where it supplies energy to the living structures of the planet by processes not totally understood. And it is emitted into the atmosphere by, you guessed it, processes not totally understood.
Consider the first of these not well understood steps consists in trying to get the water vapor to condense so as to form droplets which can become rain. This is usually taken to be my means of ice crystals which form first in the very high atmosphere and then fall turning to drops on the way down. How many water molecules does it take to make the smallest possible ice crystal? Around 275. [Sept.21, 2012, PHYSICS WORLD] Yes this scientific study says “around” 275, not exactly 275 or precisely 275 for the simple reason modern science cannot arrive at such precise information for this so common element we call water vapor. Water in other words defies simple explanation.
So you can see if even this first step is not understood than what about the other processes in the making of “ordinary” rain? They too require more research and knowledge base buildup.
All of which leads me to see better the wisdom of Pope Francis’ Laudato Si’. It is true we must respect God’s creation as a gift from Him before we can cast it in our own image. Or as the Pope says, before we make the Father’s creation into a system made in our own image.
Fr. Daniel J. McNamara, S.J., holds a PhD in Astro-Geophysics (University of Colorado) and was former Director of the Manila Observatory. At present, he is Rector of the Jesuit Community in Ateneo de Davao University.