In an effort to fight climate change, the Sahara Desert could
be going green… literally. Plans are being made to terraform
the entire Sahara desert; changing it from a dry, barren
landscape to a lush green space. If successful, the
transformation could remove 7.6 billion tons of atmospheric carbon yearly. How could we change the nature
of such a vast, isolated landscape? This is WHAT IF, and here’s what would happen
if we terraformed the Sahara Desert. The Sahara desert is 8.6 million km²
(3.32 million mi²) in size. It’s roughly the size of America — if you filled America with sand
and took away all of the trees. Terraforming an area this
massive wouldn’t be easy, in fact, it would cost about $2 trillion a year, and unfortunately, the price tag would
be just the beginning of our obstacles. What kind of environmental
domino effect would this create? Plants and trees are
the lungs of the Earth, and right now we could use a lot more of them. A single hectare of trees can absorb the same amount of
carbon dioxide you would produce by driving a car for 100,000 kilometers
(62,000 miles). If we could successfully terraform the Sahara, it would result in millions of hectares of trees being added to the battle
against climate change. That all sounds great, but what are the odds
we could pull this kind of transformation off? Believe it or not, we already have,
just on a smaller scale. China’s Kubuqi Ecological Restoration
Project saw the successful greening of one-third of the Kubuqi Desert with 70 different plant species
over a 30-year timespan. How could we scale that up for
the largest hot desert on Earth? One idea is to plant
crops and trees, and then pump desalinated water from the coast
of the Sahara to irrigate them. To prevent evaporation, the water would be carried by underground
pipes to reach the roots directly. The ideal things to plant would be
eucalyptus trees since they’re hardy, and they do well in hotter climates. Plus, they grow quickly and could
be economically beneficial for the region. As the trees began to root and stabilize, the soil would be replenished
with needed nutrients, rainfall amounts would increase, and the overall temperature of the
Sahara would cool by 8°C (14.5°F). Ok, so with time running out in
our fight against climate change, why aren’t we moving faster on
such a significant potential solution? Well first off, did we mention that
it would cost $2 trillion a year? Have fun getting international
governments to pitch in on that, especially if it’s just for the
greater good of humanity. But even if we could afford it, terraforming the Sahara Desert would
come with its fair share of issues. As the region becomes wetter as a
result of millions of new trees being planted, the risk of locust plagues increases. Yeah that’s right, locusts: the swarming pests best known
for their biblical associations. Wait, locusts can’t be that bad, can they? Well, a small swarm eats more than
what 2,500 people can eat in a day, so yeah, they can be that bad. However, the biggest problem
with terraforming the Sahara would be the environmental
domino effect it would create. The Sahara’s sand gets carried
in the air by wind power and is deposited in South America
after crossing the Atlantic Ocean. The dust picks up moisture during its journey,
and when it falls from the sky – rain comes along with it. This dust and rain combo
falls on the Amazon rainforest, helping to fertilize it and providing
the ecosystem the water that it needs. No Sahara could potentially mean
no more Amazon rainforest unless someone else steps in
with a plan to avert that crisis. So even though a green Sahara
would lower our carbon emissions, would it be worth potentially
destroying another part of the planet? Maybe instead of terraforming
one giant location, we should spread our
greening out around the world, but that’s a topic for another WHAT IF.