A large cyclone passed over the Rub' al Khali desert -

A massive stretch of unbroken sand also called “the empty quarter.”

It usually looks like this.

But after the cyclone, it looked like this.

Lakes had formed between the dunes.

The desert was filled with water for the first time in twenty years.

Then, 5 months later, it happened again.

Another cyclone hit.

Over the next year, powerful cyclones kept coming out of the Arabian sea, at a frequency not seen in decades.

It caused catastrophic flooding in normally dry areas across the region.

But especially here, in East Africa.

Today, the flood waters have receded,

but they left behind a different type of disaster:

"Millions of locusts..."

"A plague of biblical proportions."

"The worst in 70 years."

"Their impact, devastating."

"...unprecedented threat to food security."

"There's no end in sight."

This is a desert locust.

It's a type of grasshopper that lives across this area,

from Northwest Africa to Western Asia.

Typically, desert locusts spend most of their time alone, in what's called their “solitary” phase.

They really only meet with others to mate.

But if the weather starts to shift – that can lead to a transformation.

If a normally dry area becomes unusually lush with vegetation,

as it would after heavy rains,

these insects will start to congregate.

That sudden crowding triggers a hormone – and the locust starts to change, both physically and mentally.

It starts with a color shift, from a muddled brown color, to a bright yellow.

Its body shrinks and its endurance increases, which optimizes it for flight.

Its brain grows, and so does its appetite.

This is called the “gregarious phase."

They eat, and breed – leaving their eggs in the damp soil.

When they hatch, they form what are called “hopper bands”:

swarms of tens of thousands of non-flying but voracious insects that move together as a unit.

Eventually, they develop wings.

And once they take flight, it's almost impossible to stop them.

Locust swarms ride the wind, which allows them to travel up to 150 km a day.

A single swarm can contain up to 150 million insects per square kilometer.

Each one consumes its body weight in vegetation daily.

In 24 hours, a swarm of that size eats more food than 35,000 people.

Since late 2019, East Africa has been experiencing its worst locust outbreak in decades.

In 2020, the area has seen swarms as large as 2,400 square kilometers.

That's a swarm of insects over 3 times the size of New York City,

capable of eating as much food as tens of millions of people.

The swarms of bugs are so thick that airplanes have been forced to divert their course.

Billions of ravenous insects sweep through areas, decimating acres of farmland,

and threatening already food-scarce regions with famine.

"There's nothing left to harvest. There's nothing else that I know how to do."

And they're spreading. In February, Pakistan declared a state of emergency.

By late May, the swarms had reached parts of Northern India for the first time since 1962.

And the biggest factor in all of this is the weather.

Locusts reproduce exponentially when the weather is in their favor.

With every new generation, the population increases 20-fold.

So if a normally dry area stays wet for a long time,

the population will explode.

And that's what researchers think happened, starting with the 2018 cyclone.

The unusual amount of rain led to an unusual amount of vegetation,

which led to an unusual number of new locusts.

Swarms formed here, in the unusually wet desert, and made their way into surrounding areas,

including East Africa, which itself had just experienced historic flooding in late 2019,

from heavy rains caused by an unusually warm Indian Ocean.

A single “perfect storm” isn't enough to bring in swarms of locusts of this size.

It takes a series of them;

something that used to be really rare in this area.

But unfortunately, extreme weather that used to be really rare suddenly becoming more common

is one of the hallmarks of climate change.

That could mean a future with more cyclones in the desert,

more greenery where there once was sand,

and more breeding grounds for locusts.

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