It's coming this summer -- and it'll be twice as big!

Two broods of cicadas are set to emerge this year, an event that last occurred more than 200 years ago and now has scientists, bug watchers, and fans of the loud and noisy (yet harmless) insects buzzing with anticipation.

Media coverage of this popular event put on by nature is also starting, and John R. Cooley, a cicada expert at UConn, offered his expertise on the impending emergence to MassLive:

This summer, some will get a chance to witness a phenomenon rarer — and probably louder — than Halley’s comet. For the first time in more than two centuries, two big groups of cicadas in the United States will emerge simultaneously from the ground.

Cicadas, often called “heat bugs,” make their presence known throughout the country every summer by “singing” their loud song. But some of these large, flying insects only emerge from underground every so often, depending on their group, or brood.

These “periodical” cicadas bury themselves in soil, where they spend most of their lives. This summer, millions of cicadas from broods XIX (emerging every 13 years) and XIII (every 17 years) will both crawl out from underground and fly across the south and Midwest looking for a mate, according to Cicadamania, a website dedicated to tracking the insects.

The last time these two broods popped out of the ground at the same time was in 1803, Cicadamania reported – when the U.S. bought the Louisiana Territory from France.

“You cannot possibly be unaware that periodical cicadas are out, because they’re out by the millions and millions, and they’re noisy, charismatic, active insects that are just everywhere,” John R. Cooley, an entomologist who studies cicadas at the University of Connecticut, told MassLive.

“When you got them, you know it. And that’s what you can expect to see. That’s what any normal emergence looks like,” he continued.

What folks will see are a whole lot of bugs that all look the same, as the ones that come out every decade-plus look the same as the ones that come out every year, Cooley said.

Researchers are still exploring why some cicadas emerge periodically. One common theory is that their infrequent appearance helps them avoid predators and prevents enemies from synchronizing on their life cycle.

But, Cooley said this theory is flawed since all cicadas have predators, but fewer than 10 species are periodical. Some of the cicada’s natural enemies include birds, moles and Cicada killer wasps, according to the University of California Integrated Pest Management Program.

Another theory suggests the last ice age forced cicadas to evolve to have longer periodical life cycles. But, that theory is limited as many cicadas live near glacial areas – few of which are periodical, according to nature.com.

“Science isn’t all about having the explanations,” Cooley said. “We just test hypotheses and there are a lot of hypotheses as to why these cicadas are the way they are, but none really stand up so far.”

The emerging of cicadas is always a popular and trending topic, and if you have questions or are looking to cover, then let us help.

John R. Cooley is an Associate Professor in Residence at the University of Connecticut. He is an entomologist, author, and leading authority when it comes to cicadas. Simply click on his icon now to arrange a time to talk today.