And one of them, for sure, is the precision with which we can measure things, even remotely.
The tandem satellites, which are usually 137 miles apart, are sensitive to regional changes in the Earth’s mass and gravitational pull caused by the distribution of water and ice on the planet.
When the lead satellite flies over an area of increased mass, it will sense the increase in gravity and pull slightly away from the trailing satellite. Researchers can detect changes of just one micron between the two satellites …
How much is a micron? A millionth of a meter. Or put another way, the thickness of a human hair is about 100 microns.
So, we're detecting a difference of one one-hundredth the width of a human hair, on a scale of 137 miles, between two things whizzing 500 km overhead at 27,000 km/hr. (300 miles overhead at 17,000 mph, in American.)
You know what Randall would say.
In conclusion, this proves that global warming is a hoax.
(pic. source: NASA/the GRACE mission)