Summer 2019 could go down as one of the hottest on record. And it's not just the temperatures that have us sweating, there's also the anxiety dredged up by the prospect of a boiling planet. Global warming is, of course, a downer, but the one constant of fashion is that, by definition, it responds to societal change, even the catastrophic kind. Case in point: this summer's hand fan trend.

The retro accessory has been popular for a couple of years now, but in recent months, fans have truly hit max cool. The object can be traced as far back as 4,000 years ago, when an ivory-handled, ostrich feather version was included among the treasures stashed in King Tut's famous tomb. Images of the fan have been depicted on Ancient Greek pottery, as well. And the collapsible or folding fan, meanwhile, has its roots in ancient Asia. After the 1500s, thanks to the crusades and the establishment of imperial trade routes, Europeans got their hands on them. Back then, as now, fans were both decorative and useful: you could swat flies and cool yourself down all while presenting yourself as a conspicuous member of the leisure class. The hand fan was exalted as "exotic," and became symbolic of wealth and good style.

So, that brings us to 2019, when seemingly every young woman in Brooklyn now has a folding, accordion-style model ready to whip out from her tote bags if faced with a smoldering hot subway platform.

The trend has reached red carpets, runways, festivals, and, naturally, Instagram. To be a "cool girl" in summer in 2019 (literally and figuratively) is to be a girl who holds a fan in her hand, as a utilitarian accessory and symbol of style.

Take Adwoa Aboah, for example, who brandished a Christopher Kane hand fan emblazoned with the word "sex."

There's also Kacey Musgraves, whose Grammy-award winning album, Golden Hour, features the country superstar holding a pink hand fan on the cover.

Then, there was Lupita Nyong'o wearing a sherbert-shaded Versace creation for the 2019 Met Gala, the theme of which was "Camp: Notes on Fashion", and holding a confectionary-colored hand fan that, when flaccid, appeared at first glance to be just a simple clutch.

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Chaka Khan made the rounds earlier this year to promote her latest album. And you know she wasn't going to forget that signature monogrammed, bamboo-handled papillon hand fan she's been carrying for years.

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RuPaul's Drag Race winner Aquaria held one on stage while performing during San Diego Pride, and Rossy de Palma has been fanning herself on red carpets all year long.

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Is the heat melting our brains, quickening our collective descent into madness? Are hand fans just another accessory, likely made of plastic or other wasteful materials, contributing to the problem they're ostensibly designed to solve? Is the trend indicative of a subconscious response to an environmental threat against humanity, or is it simply a coincidence? There are still a few weeks left in the summer, but with these rising temperatures the heat will probably bleed well into the fall. Our forecast: fans will be all over the Fashion Week street style blogs come September.

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