Posted on 05/22/2012 9:38:49 PM PDT by neverdem
Human use of water contributes markedly to rising tides.
Climate change, with its associated melting ice caps and shrinking glaciers, is the usual suspect when it comes to explaining rising sea levels. But a recent study now shows that human water use has a major impact on sea-level change that has been overlooked.
During the latter half of the twentieth century, global sea level rose by about 1.8 millimetres per year, according to data from tide gauges. The combined contribution from heating of the oceans, which makes the water expand, along with melting of ice caps and glaciers, is estimated to be 1.1 millimetres per year, which leaves some 0.7 millimetres per year unaccounted for. This gap has been considered an important missing piece of the puzzle in estimates for past and current sea-level changes and for projections of future rises.
It now seems that the effects of human water use on land could fill that gap. A team of researchers reports in Nature Geoscience that land-based water storage could account for 0.77 millimetres per year, or 42%, of the observed sea-level rise between 1961 and 2003. Of that amount, the extraction of groundwater for irrigation and home and industrial use, with subsequent run-off to rivers and eventually to the oceans, represents the bulk of the contribution.
Taikan Oki, a global hydrologist at the University of Tokyo and an author on the paper, says that he was initially astonished at how well the teams estimates of terrestrial water usage filled the deficit between the observed sea-level rise and what was accounted for by thermal water expansion and melting ice. I didnt expect that terrestrial water storage had such a big impact on sea level, says Oki. And, he adds, I didnt expect that human extraction of groundwater would matter so...
(Excerpt) Read more at nature.com ...
[eyeroll] I bet they didn’t allow for inland locations that deal with wastewater by treating it and returning it to the aquifer. Idiots.
I was thirsty! Do ya mind?
Data from tide gauges are inadequate. They are referenced to the land itself. It cannot be established reasonably that the land has not risen or fallen with respect to sea level. The only reliable sea level indicator is taken from the viewpoint of a satellite. During one decade between the 80s and 90s, these satellite-based measurements showed a 10-year rise of 3 mm (±7mm). How ludicrous is that? And how stupid to get worked up over it.
Maybe it’s all the cruise ships displacing water, or people swimming in the oceans, or more whales, etc.
Even then, is it actually possible to take measurements from miles up in space and know that the baseline or reference altitude is stable enough to trust millimeter-scale measurements either?
For the folks from Rio Linda....\s
Biomass! When it is warm more critters and trees grow, and that takes water.
The bottled water people are producing a fair amount of new water
And I forgot to mention Iced Tea
Yes - the world has never been the same since Al Gore's 67 meter rise in sea levels
inundated Greenland, Manhattan, Florida and Vanuatu.
Most subsidence is caused by settling and decomposition of sediment. Under natural circumstances these losses were replaced by continuing deposition. Build a city on a delta, and you will get New Orleans.
Anyone want to hazard a back of the envelope guesstimate as to how many acre-feet, or hectares, or gallons might be stored on "dry land" in seven billion people?
Someone's not taking their fluid pills!
If it were all dumped into the ocean, it would probably be like pouring a bucket of water into a swimming pool. If every human on Earth were to be tossed into the ocean, I doubt it would make much difference in the water levels.
The headline is very confusing with regard to the article. They added up what they thought were sources for MORE water in the oceans, but those sources (heat expansion and melting ice) did not account for all of the INCREASE of water in the oceans. So where did this EXTRA water in the ocean come from? (So the source was unknown - or “missing”)
It would seem to make sense that groundwater “locked” in the soils for hundreds of thousands of years that is pumped to the surface, used to irrigate our fields and sustain life, and then once used either goes back into the soils, evaporates, or is flushed down the drain into the rivers and oceans will, obviously, have an impact of an increase in ocean water levels.
Development of the world into a livable and useful place often includes homes and buildings, paved driveways and roads, airports, and all sorts of other useful facilities that prevents the rain water from entering the soil, so more rain water is runoff. Finding it’s way to the nearest catch basin, culvert, creek, river and ocean.
Amazing to me that such an obvious conclusion is such a big deal to them. I wonder what other HUGE SURPRISES those that do the Global Warming modelling don’t realize to put in?
“Hey Earl - I’m wondering if we should leave a line of code open and maybe put something in there about the sun or something?”
Seven tenths of millimeter? sea level measured to an accuracy of 7/10 mm.? Right. Sure. Maybe it’s all the ship’s displacing water.
We’re all gonna die!!!!!!
Stop using water if you want to live, people!
Oh ... we need water?
We’re all gonna die!!!!!!!
I dunno, I’m just having a hard time accepting that 1.7 mm is outside of the margin of error for both the magnitude of the measurement (isn’t the ocean several kilometers deep?) and the method used (can satellites from space really measure to millimeter accuracies?). It’s kind of like using a scale calibrated to kilograms to weigh out microgram quantities, IMHO. And how do those measurements account for the constant movement of the ocean? Tides surely have *some* effect on ocean depth.
And they make fun of those medieval philosophers who supposedly tried to count the number of angels that would fit on the head of pin.
How big is a pinhead?.... The head of a pin is about 2mm in diameter.
Look, this is easy. More people drinking the water equals less water in the oceans. The oceans level goes down But more people with more water equals more weight on the land. So this additional weight pushes down on the land which is floating on the oceans and displaces more water so the ocean level rises. Net effect is no gain or loss. /S
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