Annual Sahara wind brings a chill

For a few weeks each year, the shifting winds roil southward out of the Sahara Desert, drying West Africa’s air and darkening its skies with sandy grit. The wind grounds planes, coats palm trees in yellow dust and sends inhabitants accustomed to blustery equatorial weather huddling together against an uncommon nighttime chill.

The Saharan wind, known as the harmattan, is an annual event. No long-term records exist that measure its severity, but Nigerians say this year is the worst in more than a decade.

“It’s the worst since 1994. That year, you couldn’t even see your hand in front of your face. Thankfully it didn’t last as long as this year,” said Joseph Lau, a 56-year-old deputy keeper at the Maiduguri Zoo in northern Nigeria.

At the zoo, employees shipped in extra rocks for the amphibians -- providing more spots for the snakes to warm their blood after one of the long, cold nights the harmattan brings. Zookeepers exercise the elephants each morning to ward off the chill.

For many along the West African coast, the harmattan is a nuisance that fills lungs with dust and blows in illnesses.

But for others it’s a business opportunity. Charcoal vendors move their product to buyers seeking nighttime warmth. Secondhand clothing sellers hawk knit-wool hats and ski parkas. Boys bang dust out of customers’ rugs with broomsticks. For car washers, it’s a bull market.

“I love the harmattan. It’s from Allah and it’s good for business,” says Umar Mohammed, 46, the manager of Super Car Wash in Maiduguri. As his workers remove a layer of flour-like dust from customers’ cars, he says, “It may be cold, but not for us. We’re working and we’re warm.”

The harmattan, which is caused by shifting weather patterns, derives its name from the word for “tears your breath apart” in the West African language, Twi. The wind has rated mention in European history and literature -- including Herman Melville’s “Moby Dick.” Its effect can be felt as far away as South America.

Along with the Saharan sand that darkens daytime like a maritime fog, only with the heat of a blast furnace, the harmattan brings much cooler nights: desert weather. In Kano, the main northern city, average nighttime temperature during the harmattan is about 55 degrees, versus 75 degrees in the hotter seasons.

Across West Africa, the harmattan also brings respiratory problems, as the silt enters lungs and nostrils. Farmers take advantage of the weather to burn areas for cultivation, sending great billows of smoke into the sky and compounding the breathing problems.

Nigeria’s cities are notoriously polluted, with poorly maintained vehicles and diesel generators spewing blue smoke into streets. The harmattan complicates matters, according to scientific studies.

Airborne particles can be four times heavier during the harmattan compared with the rainy season. Carbon monoxide levels are higher during the harmattan, as the wind blows southward over densely populated areas, instead of from the less-polluted ocean.

NASA satellite imagery during the harmattan season shows a heavy brown cloud squatting over tropical West Africa.

Nigerians’ attitudes toward the harmattan vary, underscoring the vast differences between Africa’s southern, coastal peoples and the northern, inland pastoralists who roam the southern edge of the Sahara and are accustomed to harmattan-like conditions.

In predominantly Muslim northern Nigeria, herd boys wander across vast plains of scrubland just below the Sahara -- an area known as The Sahel. Here, the weather is normally dry and dusty, with hot days and cooler nights, so it occasions fewer lifestyle changes than farther south.

Even in the north, though, this harmattan’s length and severity has occasioned comment this year.

Only one main airline services Maiduguri, a city of about 1 million people near Nigeria’s border with Chad, and its plane has repeatedly been unable to land due to poor visibility, stranding travelers for days.

Motorcycle drivers wear cloths, including upside down airplane eye masks, over their mouths and noses to keep out the sand. With the sun unable to warm the ground during the day, the nights have been unusually cold.

In the south, the soil is rich, water is plentiful, the countryside lush and the weather humid for much of the year. The cold and dry harmattan weather is a shock for many. The green fronds of palm trees turn yellowy-white with dust.

The city of Lagos turns a dingy gray, its vibrant colors obscured under a layer of ocher, awaiting long-sought rains.

At night, when the humidity and temperature drop, Lagos residents cram together around fires. They wear ski parkas and woolen hats sent to West Africa from cold northern countries -- even though people from those climes would find Lagos sweltering now.

Few southerners find the harmattan season as uncomfortable as the young men who harvest sand from the lagoon in Lagos. As dark falls, they sail their boats out into the enormous lake, then dive to the bottom to bring up buckets of sand, which is sold to construction companies for concrete.

“Every day is like one big cloud and at night it’s too painful and cold,” says Michael Bayo, 28, a sand digger who has never traveled far from his home in Lagos, a city of 14 million people. “It’s so cold, like it must be in Europe.”