If you take a look at the rest of the planets in our solar system, you quickly realize that the Earth is unique. Earth, after all, is the “water planet” with nearly 75% of its surface covered in beautiful, blue water and glistening white icecaps.
Life as we know it depends solely on water. Without it, we don’t survive.
Where Did Earth’s Water Come From?
When trying to find out more ourselves we look at a number of things; family history, public records, DNA, census info, etc. So, when scientists are studying the Earth’s water sources, they do the same thing; they look at a number of sources. Since there is no “recorded history” of the Earth’s water, this is the only way to find data. Much like a forensic investigation of a crime scene.
Heat Made the First Drops of Earth-Water Possible
Earth’s water chemistry is simple: Two hydrogen atoms stuck with one oxygen atom. That’s the H2O molecule we’ve all come to know as water.
Hydrogen came about very soon after the Big Bang. Oxygen took a little more work to get going, though. And it needed stars to help get it started.
Fast forward about a billion years after the Big Bang.
The cosmos was full of stars, both interior and exterior stars. Inside of the interior stars, there were more complex elements being fused together because of the immense heat.
Oxygen was one of these elements.
When stars die, they go “supernova”. They explode and throw these elements with great force outward.
That’s where the chemistry comes in: The hydrogen of the Big Bang runs into the oxygen from supernova stars being thrown together by the force of the explosion.
How Can Scientists Be Sure Water Came to Earth rather than Already Be Present?
Based upon what scientists know about Earth’s history, they know that the planet went through long stretches of extreme climates, extreme temperatures, and no protective atmosphere. That would have caused water molecules already present on Earth to evaporate back into space.
That’s why scientists believe that water we have now was actually cooled and formed in space and as our planet cooled, it developed into the atmosphere we enjoy now.
Everyone and everything that has lived on Earth since then has enjoyed the water. From the earliest microorganisms and the dinosaurs to our grandparents and our grandchildren.
Although 73% of the Earth is covered in water, only 2.5% is actually freshwater. And as we know already from Earth’s hydrologic cycle, the amount of water on the planet doesn’t change, only the form.
The Water We Have Access to is Precious
That means we only have easy access to a fraction of the world’s water. Although there is 2.5% available, most of that freshwater is locked up in frozen form within glaciers, deep underground, or ice caps.
With climate change, the ice caps and glaciers are melting at a very accelerated rate. Satellites allow scientists to see the “big picture” and collect all of the data they need to determine what is going on with Earth’s climate on a global scale.
Rain is Life
Most of the freshwater that we have access to is via precipitation. Since 1997, NASA satellites have been measuring and monitoring rainfall around the globe. In 1997, the NASA Tropical Rainfall Measuring Mission (TRMM) was launched. TRMM continued it’s mission for 17 years until it was decommissioned in 2015.
During those 17 years, TRMM helped us tremendously in understanding climate, weather, and even helped technology determine when a tropical storm will become a hurricane.
The Water Circle of Life
The hydrologic cycle is a wondrous thing. The next time you get a chance to drink water or wash your face, give some thought into the fact that the water you’re using was more than likely raindrops just a week or so prior. Municipal reservoirs are just a very large scale of rainwater harvesting.