Posts Tagged ‘our amazing interconnectedness.’

What protects and feeds the earth?

Dust!

Every year, over a hundred million tons of dust is picked up from the deserts of Africa by mountain winds — picked up from the massive Bodélé Depression, the “dustiest place on Earth,” picked up from the giant old lake bed of Mega Chad, and blown across the Atlantic Ocean.

7,000 years ago, the Sahara wasn’t a desert at all, but a land of huge lakes, and the largest was Chad, bigger than all of the Great Lakes combined.

Much of the dust consists of fossilized microorganisms, diatoms, billions of diatoms that fell to the bottom of the lakes as they evaporated.

Diatoms are micro-algae. They are the only organism on the planet with cell walls composed of transparent, opaline silica. Diatoms live in houses made of glass.

So billowing clouds of desert dust — glass diatom houses — from the Sahara waft into the atmosphere, form a plume that stretches 4,000 miles — more than the size of the continental United States — and head out over the Atlantic Ocean. There, in part, the dust clouds play the role of hurricane spoiler. The dry air shreds the forming clouds.

Some of the Saharan dust falls into the Atlantic and sinks to the bottom. Full of nutrients, it feeds the phytoplankton. They in turn help create our oxygen.

Some of the dust keeps going, traveling high in the atmosphere. An estimated 27 millions of tons of Sahara dust reaches the Amazon. Water vapor in the Amazon nucleates on the dust particles, and mineral-laden rain falls — fertilizer from the sky.

This is needed. Surprisingly the Amazonian soil is poor. The heavy rains wash away its phosphorus. The Shaharan dust adds back in phosphorus, present in its microscopic diatoms.

One of the driest places on earth nurtures one of the wettest. Former lives feed current lives.

The interconnectedness of the earth is astonishing. The complexity of our ecosystem is amazing. The sequencing is first rate.

I can just imagine God working this all out ahead of time saying, “Hum, what if we solved that problem with this solution. Dust. Cool!”

Then he paused and said, “I can do a lot with dust.”