14 DAY TRIAL // A new scientific study shows that, during heavy storms, the smaller droplets of water falling from the sky are actually traveling faster than others, and also faster than they should be able to. The find, which scientists say is like discovering the meteorological equivalent of breaking the light-speed barrier, could ultimately help weather experts establish new rain patterns, as well as get a better understanding on how large thunderstorms operate.
The thing that annoys researchers the most is the fact that the small rain drops behave in a manner that is inconsistent with the laws of physics. That is to say, by all accounts and purposes, the heavier droplets should fall to the ground faster, because they have more mass, which allows them to better overcome wind resistance. However, for quite some time now, meteorological observers have known that the smaller droplets sometimes reach the ground at the same time as larger ones.
In a groundbreaking new research, experts from the Michigan Technological University (MTU) in the US, and the National University of Mexico in Mexico City, have finally managed to establish for a fact that the previous readings were not the result of some faulty instrument reading, but a very accurate phenomenon. ScienceNow reports that the science team analyzed the falling patterns of more than 64,000 rain droplets falling in New Mexico over the past few years. However, not all rains were analyzed, but only those that occurred in calm weather, when the wind was not an important factor.
Results revealed that some of the droplets fell faster than their terminal velocity, which is basically a speed limit of sorts that is reached when the accelerative force of gravity – pulling objects down – is finally counteracted by air friction. When this limit is achieved, the rain drop, or any other object, continues to fall to the ground with a constant speed and stops accelerating. The researchers were especially interested in superterminal drops, which are created when larger drops collide while falling. This sends a plume of speeding droplets around them, and their proportion decreases as they get closer to the ground. At the same time, the proportion of speeding droplets increases.
“What surprised us was not so much seeing the superterminal drops, but seeing the deeper, compelling patterns. [The find is] consistent with the notion that large drops break up to produce a swarm of speeding satellite droplets. Weather forecasting models depend on simplified theories of how raindrops grow, [so] the more we understand about the interactions between drops, the more we can improve our ability to predict whether it will rain on tomorrow's picnic,” explained MTU physicists Raymond Shaw, who is also the co-author of a new study detailing the find, published in the journal Geophysical Research Letters.