As a child growing up in Northern Germany, I vividly
remember that, if it was not raining, it was snowing. On rainy days, Mom insisted that we
play inside. My older brother and I
would spend hours upon hours sitting on the window sill of our 2nd
story bedroom longingly peering outside in hopes to catch a glimpse of the sun,
so we could once again go outside to play.
We would also look at the clouds passing overhead, and point out
familiar figures. “Look that cloud looks
like a deer. That one looks like an elephant’s
trunk.” As soon as we saw just a hint of
blue, we would run downstairs and beg Mom to let us play outside once more.
One day, I must have been seven or eight years old, I
recall, playing outside with my friends, something amazing happened. We looked up at the sky, and wonder upon
wonders, there was not a cloud in sight!
We had never experienced that before!
We ran from door to door, ringing our neighbors’ doorbells and telling
them: “Look at the sky! It looks like a picture postcard. There is no cloud from one end of the sky to
the other!” It was magic!
A few years later, my father was transferred from the cold
of Northern Germany to the warmth of Southern California. Here, it seemed the sky was blue all the
time. Rarely would we experience the
magic once more of looking the clouds and interpreting their shape.
On the first day of the school year in California, our
English teacher gave us an assignment so each student could learn something
about our classmates. We were instructed
to create a collage of magazine pictures to tell a story about an experience
that fascinates us. A few days later, we
had to go in front of the class and give a talk about our collage.
I poured over magazines and colored flyers. I cut out pictures to show the difference between
the grey skies I had grown up with in Germany, and the beautiful blue sky, and
the beautiful sunsets I had now seen in my new home, California. I was really nervous and scared to have to go
up in front of the class and tell them in my still broken English about my
collage. But, I felt, that a picture can
tell a thousand words, and mustered up all my courage to proudly stand in front
of my new classmates to share it with my class.
My enthusiasm was dampened by the reaction of my
classmates. In fact, they laughed at my
work. You see, since I did not know
enough English yet, I was unable
to digest the headlines and current event news stories in the magazines. I had simply clipped out pictures that would
contrast the grey skies vs blue skies and sunsets over the ocean.
Unfortunately, I had chosen pictures showing the grey and
sunless skies had a nuclear power plant in the foreground. The news story must have been protesting a
power plant coming online. Several of
the pictures of blue sky over Southern California scenes and brilliant sunsets
over the ocean were ridiculed too. My classmates
were quick to point out the brown layer of air pollution hovering over the city
and ocean. They matter-of-factly
informed me that the more pollution and particles were in the air, the more
brilliant the colors of the sunsets would appear. I was shattered. What I had perceived as beautiful was
regarded as despicable and ugly by my peers. In fact, I did not know at that time that just breathing the air in Los Angeles, was
equal to having a 2 pack of cigarettes a day smoking habit.
In later years, in an effort to get away from the polluted, dirty
air of Southern California, we headed for vacation spots in the Caribbean. We figured, that the air quality would be
great there: no heavy industry, no bumper-to-bumper traffic with gas-guzzling,
highly polluting cars. Well, guess
what? We were in for a new surprise.
Enter the Saharan Dust Clouds. Wait, how can that be? The Sahara is so far from the Caribbean! What is going on?
Located in North Africa, the Sahara makes up 31% of the
African continent. Its area encompasses 3,600,000
square miles (9,200,000 square kilometers) making it the world’s largest hot desert. When high-speed winds pick up tiny dry
particles from the desert surface they create dust plumes. Every summer, this natural phenomenon from
the Sahara blows off Africa and across the Atlantic Ocean. This phenomenon has been studied since the
early 1970s.
In some years, these dust plumes have not been substantial,
and have sunk into the oceans. In other
years, when they passed over the Canary Islands, the dust plume appeared like a
fog that reduced visibility and deposited a layer of dust onto everything. On January 8, 2002, the dust was so thick,
public life and transport came to a standstill. Visibility had dropped to 160 feet (50
meters) and the Tenerife South Airport was forced to close.
In other years, during a strong episode in July 2000, the
trade winds carried the thick plume across the Atlantic Ocean. In Puerto Rico alone, it was estimated that
this episode deposited one-fifth (or the equivalent of 8 million metric tonnes)
of the annual dust deposits that one month.
Twenty years later, in June 2020 the plume was so massive that it was named “Godzilla”. It has been the thickest or dustiest since records have been kept of these events. Godzilla contained 70% more dust than in a typical year. It also appeared to have traveled further than previously recorded events. The plume of dust was carried about 5,000 miles (8,000 kilometers), passing over the Caribbean islands and ending up over the southeastern United States severely affecting air quality along its path.
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Satellite data showing the Sahara dust plume nicknamed Godzilla in June 2020. (Image credit: Modified Copernicus Sentinel data (2020), processed by ESA, CC BY-SA 3.0 IGO) |
As with everything in nature, there are both positive and
negative things associated with the Saharan dust plumes.
On the positive side, according to the National Oceanic and
Atmospheric Administration (NOAA), the plumes can inhibit the formation of
hurricanes, or prevent the storm systems from becoming more powerful and
destructive.
Another positive aspect is that the plumes carry along vital
nutrients such as iron and phosphorus.
Both phytoplankton in the ocean and plants on land need these nutrients
to grow. A 2017 study found that more
than 70 percent of the iron available to the ocean’s photosynthesizing
creatures is deposited by the Saharan dust plumes.
On the negative side, the air quality across the Caribbean
reached severely hazardous conditions during these events. You see, dust clouds
are a concentrated delivery system for fine particles that harm human health,
especially resulting in respiratory distress and diseases.
Another negative has been pointed out by some sources who claim that the proliferation of Sargassum over
the past 10 years can be directly attributed to a greater than normal amount of
nutrients deposited in the Atlantic. In
the summer of 2015, these algae created a crisis in the Caribbean when
large quantities of Sargassum accumulated on the shores of the islands and the
Caribbean Coast of Mexico. This was
repeated in 2018, with 6,000 square kilometers of Sargassum coverage, which was
double the amount of the 2015 event. The last 3 years have turned out to be record years for this phenomenon, with 2023 being the worst yet.
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