Europa Has Plate Tectonics


“Plate tectonics” – “Plate” a geologic term for large slab of rock, and “Tectonics”, part of the root in Greek for “to move” – put them together – suddenly ocean currents, weather patterns, and an average global temperature of 54 degrees Fahrenheit start to make sense. Science accepts the theory of moving plates of rock – 7 major and over a dozen minor plates, making up the Lithosphere. A 100 Kilometer deep  (give or take, here and there) outer crust  floating about on hot layers of  upper mantle.

Tectonic plates couldn’t exist without water. As our world took shape billions of years ago – water was the single factor capable of setting life in motion – accretion settled down, planet Earth announced she was here to stay – it was water that set our unique set of circumstances in motion. There’s a lot of it beneath the surface – perhaps as much as an entire ocean – pooled, saturating, running and generally messing around with otherwise solid stone. Our planet was precisely the proper size to form and cool – not too fast, not too slow, but just right. Mars tried to develop tectonics, science speculates it had an atmosphere and magnetic shield for a cosmic blink, but ultimately proved too small (hence cooled to fast) to make it in the long run.

Plate tectonics are tricky – on Earth they are credited with formation of mountain ranges (the Andes and Himalayas for instance), geographic barriers responsible for trapping moisture, continental drifts and collisions (Antarctica separating from Australia – hence redirection of ocean currents) or volcanic eruptions which released trapped carbon dioxide gas leading to global warming.

Plate tectonics are the reason we have earthquakes – ever drifting sections of the planet grind against each other, exert unimaginable pressure as one plate attempts to overtake another – inevitably very bad days follow. Earthquakes, volcanic eruptions, monsoons, hurricanes – all products of our unique tectonic designation. I could write pages about Earthly tectonics, but ask  you trust me when I tell you – they are the reason we exist. At the moment, I have Europa on my mind.

Europa is the 6th closest of Jupiter’s 63 moons. It caught Galileo’s attention in 1610 (a ponder in itself – why this moon Galileo?). Of interest to NASA since the early 70’s, modern science suspects Europa’s smooth icy surface hides a liquid ocean – data from the Hubble telescope indicate “plumes” of water vapor spewing from a suspected underground source. Earlier this week, researchers S.A. Kattenhorn and L. M. Procter published findings culled from Hubble images indicating tectonic movement on Europa. Using images from Hubble, they concluded Europa’s surface appeared to move about, much like our own – a conclusion with only one explanation – plate tectonics.

Plate tectonics rely on water, water is the one and only constant needed to support life. We’ve long believed Earth was unique regarding tectonics and the ramifications of liquid water  in relation to supporting any form of life. Pondering Europa as a planetary body with plate tectonics means it’s possible life exists beneath the surface.

http://www.scientificamerican.com/article/jupiter-s-moon-europa-has-plate-tectonics-like-earth-s/

NASA’s Jet Propulsion Laboratory has conceptualized a mission dubbed “Europa Clipper”, with an optimistic launch in the next 10 years. Despite a daunting 2 billion dollar price tag, NASA is asking the scientific community to submit suggestions by October 17, 2014 for instrumentation or investigative approaches to determine once and for all if Europa has what it takes to support life.

“Life” is complicated. Plate tectonics  may be tricky, yet one thing remains unshakeable – life exists on Earth due to tectonics – we owe it to ourselves to investigate that possibility on Europa.

Why Pole Ice Matters


Melting ice caps mean a whole lot more than rising ocean levels. Arctic Tundra, thawing permafrost, diminished ice packs – seemingly insignificant, yet crucial on a global scale. I found and linked to this wordpress site, one able to explain the balance far better than I could.

http://wildtracks.wordpress.com/world-ecosystems/tundra-ecosystems/arctic-tundra-ecosystem/

As critical as the Arctic might be, it’s Antarctica that has me pondering. Would you believe me if I told you Antarctica is responsible for global weather? How about being the source of ocean currents responsible for maintaining ocean temperatures within a degree of average at all times?

Hovering at a consistent minus 110 degrees Fahrenheit during the total darkness of six month winters (43 degrees Fahrenheit colder on average than the Arctic) Unprotected by land masses, pummeled by constant 100 mph winds courtesy the “polar jet” ( a product of warm tropical air colliding with cooler south pole air masses – a conflict producing massive storms up to 4000 miles across). Polar winds, fed by earth’s rotation produce upper atmosphere winds of 200 mph. At the same time, churning water around Antarctica all the way to the ocean floor.

This is where it gets interesting. At 29 degrees Fahrenheit water begins to freeze, accounting for Antarctica more than doubling in size during “winter”.  As sea water freezes, salt separates becoming dense, heavy “brine”. Billions of briny gallons slowly fall to the sea bed – an unseen ocean waterfall, flowing away from Antarctica and over the continental shelf, coming to rest several miles below.  Thanks to raging “Polar jet” circulation, brine barely has time to catch its breath before the “screaming 60s” (below 60 degrees latitude, the roughest seas in the world), send it packing for warmer waters.

Urged by relentless circular motion, dense brine begins to move. Finding warmer water towards the Equator,  it starts to rise, taking along rich nutrients and minerals from the ocean floor. Flows of deep sea brine follow prevailing winds – in a nutshell, regulating ocean temperature, providing nutrients for plankton blooms and acting as the global barometer keeping weather in check. Joining other ocean currents, rising, falling, becoming diluted on the way up – the coldest, densest water known to man regulates average ocean temperature within a degree.

Ponder this irrefutable fact – without Antarctica and the polar jet, we have absolutely no way of regulating weather. Everything we take for granted – seasons, tropical monsoons, snow pack maintaining glaciers – without exception, the result of ocean circulation patterns. Antarctica protects the world from wild swings in temperature, end of story.

http://oceanservice.noaa.gov/education/kits/currents/06conveyor2.html

My simplified  explanation of the process can’t begin to convey the importance of polar ice. Antarctica in particular plays a role vital enough to be called crucial to our way of life. We need to stop dickering over who or what is to blame and start grasping it won’t matter once the ice is gone.

A link to the state of Arctic ice….

http://nsidc.org/arcticseaicenews/

 

Global Wind Map


Every so often I stumble upon an app or site capable of reducing me to a child cut loose in a toy store. OK, so I’m a weather nut, no shame in that. Nor surprising my toy store is an interactive map of global winds and ocean currents.

Weather is humbling – despite technology, scientific advances and satellite tracking – we’re powerless to stand between our lives and a bad storm. Rarely given the respect it deserves, blissfully unaware nature doesn’t care who you are or where you live, blinded by a bloated sense of entitlement – weather resides in the land of local forecasts and grade school felt board representations. Smiley suns, puffed blowing cheeks of grumpy looking clouds – weather reduced to robotic statistics following sport reports.

Weather can’t be dismissed as “local” or “national” – weather is global, an intricate symphony of cause and affect. The top ten feet of oceans hold as much heat as the entire atmosphere. Ocean currents move and redistribute heat. Hurricanes form only when surface water reaches 79 degrees Fahrenheit – the tipping point where evaporation meets rotation of the earth – unstoppable, inevitable and indiscriminate.

Wind carries upwards of 200 million tons of “mineral dust” from the Sahara into the atmosphere every year.  Transported thousands of kilometers in the upper atmosphere, mineral dust deposits fuel plankton blooms (resulting in increased fish) reduction of ocean temperatures (fewer hurricanes), rejuvenated Amazon rainforests, and stunted growth of coral reefs in the Caribbean. Unpredictable, impossible to anticipate – at the mercy of natural forces we can only stand back and witness.

When I stumble upon a tool to observe nature in all her glory I go slightly bonkers. The first link below is to a page highlighting the virtues of an interactive global wind map. You can watch global wind or ocean currents, adjust settings for specific countries, atmospheric height or chuck wind and focus on ocean currents. The second link takes you directly to the interactive site – one I hope you find time to play with after wetting your appetite on the overview.

http://io9.com/this-real-time-global-wind-map-will-completely-devour-y-1482867032

http://earth.nullschool.net/#2014/06/23/0600Z/wind/surface/level/orthographic=-91.64,46.36,256

earth.nullschool.net