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Monday, July 1, 2019

Typical Summer Hailstorm Causes Climate Change Hysteria

By Chris Martz | July 1, 2019



Did you hear about the hailstorm that just recently hit Guadalajara, Mexico (Figure 1)? 

Figure 1. Hail cleanup in Mexico.
You likely did and while impressive in photos, it was nothing out of the ordinary for the region. It's once again, wacky journalism and scientific illiteracy that has you all hyped up and in panic mode. Numerous articles have surfaced, like this one from CBS News describing how "6 feet of hail fell on Guadalajara, Mexico" (Figure 2).¹ Please note that I have nothing against CBS News, I'm just pointing out the simple fact that the article is a bit misleading...

Figure 2. Freak hailstorm dumps up to 6 feet of ice on Guadalajara, Mexico - CBS News.
Social media (i.e. Twitter) started to jump on the bandwagon train after articles like this were published, and it didn't take long before people began to blame global warming, climate change, the ecological breakdown, climate crisis, global heating, global change, or whatever they call it nowadays on the "freak" hailstorm. 

The governor of the Mexican state Jalisco, Enrique Alfaro, suggested that climate change may be the cause of the hailstorm.¹ The entire problem with that mindset is that climate change — regardless of the main cause — does not actually cause [extreme] weather events. Climate change itself may amplify or reduce extreme weather intensity or frequency to a degree, but it most certainly does not cause extreme weather to occur. It is unknown whether or not a certain weather event would occur in a warmer or colder world, considering that events like hailstorms have occurred for as long as we know.

What Causes Hail?

Hail itself is a common occurrence during summertime, as they form from frozen water droplets that collide with supercooled water droplet suspended in the air by thunderstorm updrafts.² ³  The stronger an updraft is, the longer the hailstone stays in the air colliding with more supercooled water droplets, and as a result, the larger the hailstone grows.² ³  Eventually, it along with other hailstones become too heavy, and fall to Earth's surface from the thunderstorm updraft.² ³ ⁴ (See Figure 3).


Figure 3. Hail formation - original image from Brad Panovich.
Hailstorms in NW Mexico Are More Common Than You Think

Like hail, lightning is a good indicator of thunderstorms. The map below (Figure 4) shows the average annual number of lightning strikes per square kilometer across the globe.² As you can see, western, mountainous Mexico — where Guadalajara is located  sees a high number of lightning strikes per year, as compared to other areas.² This is a good indicator of frequent hailstorms.


Figure 4. Lightning flashes per year.
A 1977 study of North American Hail by Stan Changnon Jr. found that hail is most likely to occur during the Spring and Summer months in the Central Plateau and high mountains of Mexico, while simultaneously less common around coastal mexico and the Yucatan Peninsula.²  Moreover, mountainous regions experience on average, four or more "hail days" annually.² 

While average annual lightning strikes — as previously stated — are a potential indicator of more hailstorms as Dr. Marshall Shepherd noted, it's certainly not applicable to all locations. For instance, Florida has the most annual number of thunderstorms in the U.S., but at the same time less hail than Colorado, Nebraska, and Wyoming — commonly referred to as "hail alley."² Those three states on average have seven to nine hail days per year according to NOAA.² The reason for this is because the freezing level in the atmosphere — where temperatures fall to freezing — is closer to the ground due to mountainous terrain as compared to Florida's flat terrain.² The same can be said about Guadalajara, which sits at an elevation of 5,138 feet.² ⁶ This high elevation, once again means that the atmosphere's freezing level is closer to the ground, thus it should be to no surprise that hailstorms are a somewhat common occurrence.

Meteorologist Dr. Roy Spencer, of University of Alabama Huntsville (UAH), found this hand-drawn map (Figure 5) of global hail frequency from a 1973 study. The map clearly shows that Guadalajara receives a great number of hail days per year. Somehow, journalists completely omitted this.


Figure 5. Global hail frequency.
What About That "6 Feet of Hail?"

This simply didn't happen. Six feet of hail did not fall out of the sky onto Guadalajara. When major hailstorms occur, heavy rain is often present, and as we know, heavy rain causes flooding.⁷ This flooding causes currents of water to flow through streets, in which hail becomes deposited into large, scattered piles.⁷ 

The Summary of It All

It should be eye-opening to you that people actually think every weather event is this existential crisis. It should also be eye-opening to you that people think every weather event that occurs has "never happened before." Perhaps it's just me, but I have seen a frightening rise in this mindset among people, that's politically motivated. 

As I have been saying for quite some time now, it's very important that people take a step back and look at the mechanisms and causes, rather than assuming it's climate change at work. This narrow view of catastrophic climate change continues to advance down a very dark path that needs to have it's brakes applied on immediately.


REFERENCES

[1] Brito, Christopher. "Freak hailstorm dumps up to 6 feet of ice on Guadalajara, Mexico." CBS News. July 1, 2019. Accessed July 1, 2019. https://www.cbsnews.com/news/mexico-hail-storm-up-to-6-feet-of-ice-dropped-guadalajara-north-mexico-city-in-summertime-freak-hail-storm-sunday/.

[2] Shepherd, Marshall. "Why Caution is Needed With Those Hail Pictures in Mexico." Forbes. July 1, 2019. Accessed July 1, 2019. https://www.forbes.com/sites/marshallshepherd/2019/07/01/why-caution-is-needed-with-those-hail-pictures-in-mexico/#759936502cf5.

[3] "How Does Hail Form?" NASA Precipitation Education. Accessed July 1, 2019. https://pmm.nasa.gov/education/content/how-does-hail-form.

[4] "Thunderstorm Hazards - Hail" NWS JetStream. Accessed July 1, 2019. https://www.weather.gov/jetstream/hail.

[5] Changnon, Stanley. "The Scales of Hail." Journals of Applied Meteorology. April 22, 1977. Accessed July 1, 2019. https://journals.ametsoc.org/doi/pdf/10.1175/1520-0450%281977%29016%3C0626%3ATSOH%3E2.0.CO%3B2.

[6] "Guadalajara." Wikipedia. June 23, 2019. Accessed July 1, 2019. https://en.wikipedia.org/wiki/Guadalajara.

[7] Spencer, Roy. "The 'Freak' Guadalajara Hailstorm wasn't So Freakish." July 1, 2019. Accessed July 1, 2019. http://www.drroyspencer.com/2019/07/the-freak-guadalajara-hailstorm-wasnt-so-freakish/.

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