Monday, July 24, 2017

The deep, dark ...

Among the things we know the least about -- the deep, dark ocean depths.  Important but missing pieces of our understanding will be found there, at least for scientists.

Deep ocean currents are simplistically understood, but we've never been there. Ocean currents circle the globe and deep segments take centuries to finish the trip.  They move more than just water - the energy transfer by ocean currents is greater than all the wind and storms and heat absorbed by the atmosphere.

Recent discussions about climate change have focused on atmospherics and greenhouse gas accumulations with associated temperature change, but ... the oceans absorb much more energy than the air does.

Around 90% of excess (over-balance) heat from recent decades is now stored in the ocean.  Around 60% of it settled in the upper ocean, the top 700 meters or so.  Another 30% resides much deeper.  "Though the atmosphere has been spared from the full extent of global warming for now, heat already stored in the ocean will eventually be released, committing Earth to additional warming in the future." (ref)

The problematic part is that ocean currents are mechanical constructs, they are energy-driven conveyer belts that happen to stabilize our climate.  Now, though, their patterns and rates will change as the currents adjust to additional (over-balance) energy.  Notice how currents carry the climate to northern Europe and to Central and North America, and from the western Pacific and Indian Ocean down to Antarctica.  Climate is beginning to reflect the newly energized conveyer belt and we'll have to adapt.  Crops will need to be altered eventually, energy needs will change, and the rules for life will adjust.

While the doom-cryers warn of drought and melting ice, we can expect the ocean scientists to bring us some missing pieces, perhaps soon.

The newly deployed Deep ARGO sensor suite can, now for the first time, reach the ocean floor.  A clever fleet of automated devices, they descend and measure along the way, drifting with the currents, then once a month, they surface and report their data.
We've known for some time that the deep ocean is changing, but the data on temperature and chemistry is sparse.  The information emerging, particularly from Deep Argo, will broaden our understanding of what is actually happening.
While there is much discussion about global warming's cause, the important reality is perhaps in front of us.  Heat energy added to our oceans now affects us.  Heat conveyed from the warmest zones will melt polar ice and will warm the glacial land regions.  Rain patterns will change.  Forests will migrate, and arable regions will morph.  There's no comprehensive model yet to tell us where the changes will be most significant, only that it is on the table to be addressed, and that our children and grandchildren will see the effects which, once begun, will persist for centuries..
While we live our high-speed, short-attention-span lives with wind and weather in view, the greatest energy accumulation will continue to be in the oceans, and the greatest effect on climate will be driven from there.  It won't happen overnight, but it will happen over decades, perhaps just a few.

We dump about 14 billion pounds of trash - most of it plastic - in the ocean every year. Industrial, agricultural, roadway and residential runoff have changed the ocean's chemistry.  About 1.2 million barrels of oil are spilled into the ocean each year from pipelines and transport vessels.  Such things along with the 90% of over-balance heat don't just disappear.  The balance of life, heat, and motion in the oceans has changed, and we will live with the effects for centuries.  I expect the oceans will be the finale to our inquiry.  Reasonable discussion regarding objective facts will help, of course.

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