In January, 2006 a 200 lb chunk of ice landed in the back seat of a red Ford Mustang, totaling the pony car. Later, in April of that year a huge ball of ice fell out of the sky and left a sizeable hole in the ground at an Oakland, California park. ABC News, 4/10/06. In fact there have been at least 50 such icefalls recorded since 2000, ranging in size from one lb to a 400 lb monstrosity that crashed through the roof of a Mercedes Benz factory in Brazil.

Typically these events occur under clear skies. And no, these ice chunks were clear, free from urine, feces and blue disinfectant that would indicate a septic discharge from an airplane. So where did they come from?

Incident in Spain Causes Planetary Scientist to Seek Answer

During January, 2000, hunks of ice weighing up to 6.6 lbs. rained on Spain over the course of ten days, all under cloudless skies. Planetary geologist Jesus Martinez-Frias became intrigued by the incident and formed a team that continues to investigate the phenomenon. Frias named the ice chunks megacryometeors. He includes the term ‘meteor’ not in the more common sense of an object from space, but because he is convinced that the objects are meteorological phenomenon, originating near the tropopause, the border between the troposphere and the stratosphere.

The troposphere is the lowest region of the atmosphere, extending from earth to an average altitude of 6.8 miles, or 36,080 feet. It is the only layer of the atmosphere in which weather occurs. Frias’s hypothesis is that megacryometeors form when an ice crystal is repeatedly tossed about by strong turbulence through regions rife with cold water vapor. Eventually, they will acquire sufficient mass to overcome the atmospheric turbulence and fall to earth.

Frias believes that both turbulence and water vapor have increased at the tropopause due to climate change, specifically warming of the troposphere and concomitant cooling of the stratosphere, interacting to make the tropopause colder, wetter, and subject to more extreme updrafts and wind shears. If this is the case, incidents of falling ice could become more common. That prediction cohabits with the smash landing of a microwave-sized ice ball in Douglasdale, South Africa on July 10, 2007, the first suspected megacryometeor recorded on that continent.

Megacryometeors Have Much in Common with Hail, but Without the Thunderstorms

Parts of ice chunks have been studied by the Frias group and others. Reportedly, they share the same textural features and composition as large hailstones. After examining a chunk of ice that fell near Madrid, Frias concluded: “The water in the megacryometeor is clearly tropospheric.” Chemical Science, 2/26/08. Scientists are in agreement in doubting an extra-terrestrial origin. Though they concede that there are pieces of comets out there, “it’s extremely unlikely” for a cosmic hunk of ice to make it to earth’s surface, “mainly because of the shockwaves it encounters as it’s entering the atmosphere.” Ryan Diduck, Chabot Space and Science Center.

Yet Frias’s theory raises some confounding questions. Why don’t megacryometeors fall during extreme, hail-producing weather, when the turbulence in the troposphere should be at its most violent? And monster hailstones forming in a cloudless sky defies more than a century of research on hail formation. Even Frias admits: “I’m worried that great blocks of ice are forming where they shouldn’t exist.” Why also would giant hail-like chunks fall singularly, unlike hail which arrives in pelting fusillades?

A Simple Answer

Meteorologists have had a hard time wrapping their heads around the Frias hypothesis. A vocal detractor has been Roy W. Spencer, PhD, University of Alabama at Huntsville. He is convinced that the big chunks are falling from aircraft, though not the washroom. Freshwater systems aboard these planes may leak, forming layer by layer a big chunk of clear ice that eventually disengages itself and falls to earth. Of the Oakland incident, Ron Wilson, aviation consultant for KGO TV in San Francisco, said that the icefall could have come from a plane if a freshwater valve leaked at high elevation. “That sometimes leaks, and will build and build and form a good chunk of ice.”

Questions Remain

Freshwater from an airplane would be chlorinated, and that would show up in a chemical analysis, and thus far analysis of the ice shows it matches the composition of the rain for the region it fell on. Frias and his team also claim that reports of falling ice date back at least to the 19th century, before there were airplanes. Dr. Spencer, for one, would demand clear and convincing evidence of such claims. As of yet, there are no hypotheses that have universal acceptance from scholars.

Still, big icefalls have punched holes in the roofs of houses, smashed through car windows, and whizzed past people’s heads. At least one scholar is keeping an open mind. Bernd Michael Rode, professor of theoretical chemistry at the University of Innsbruck in Austria said: “The (Frias) team’s work shows that our atmosphere still provides surprising and unresolved problems.”