Posts tagged oceans

video link

rjzimmerman:

Trailer for a new documentary entitled, “Sonic Sea,” produced by the National Resources Defense Council (NRDC), and which will premiere on the Discovery Channel on May 19. Description of the documentary from NRDC:

Beneath the surface of our oceans lies a finely balanced, living world of sound, most of which we never hear topside. But to whales, dolphins, and other marine life, sound is survival, the key to how they navigate, find mates, hunt for food, communicate over vast distances, and protect themselves against predators in waters dark and deep.

Our oceans, though, have become vast junkyards of industrial noise — often louder than a rock concert — from commercial shipping, military sonar, and seismic blasts that test for oil and gas. The seas have become so loud, in places, that these great animals are drowning in noise that threatens their health, their future, and their very lives.

On May 19, the Discovery Channel will premiere an important new NRDC film that documents this shattering underwater peril. Sonic Sea calls on us to turn down the volume before it’s too late.

To the future of marine life worldwide, deafening noise is hardly the only threat. It is compounding the stress ocean life faces a growing litany of environmental ills.

Current fish wet biomass is about 2 billion tons, so removing them won’t make a dent either. (Marine fish biomass dropped by 80% over the last century, which—taking into consideration the growth rate of the world’s shipping fleet—leads to an odd conclusion: Sometime in the last few years, we reached a point where there are, by weight, more ships in the ocean than fish.)

https://what-if.xkcd.com/33/

The GRACE satellites are a pair of twin observing devices that orbit the Earth 137 miles from one another. The Earth’s gravitational pull on the satellites varies depending upon the mass of what is below them at a particular time — a mountain, an ocean — and so by measuring slight perturbations in the distance between the two satellites, scientists detect these mass changes. But when does the Earth’s mass change in a significant way, one that would suggest an important anomaly? Mostly, this does not happen with the ground, rocks, mountains — at least not on human time scales. But water at the Earth’s surface moves around a great deal — California’s drought has been picked up by GRACE, as has dramatic melting of the glaciers of Alaska.

https://www.washingtonpost.com/news/energy-environment/wp/2015/11/04/nasa-can-now-detect-worrying-ocean-circulation-changes-from-space/