What goes down must come back up

Nov 20, 2012 by Alan Buis
A new NASA study finds that global sea level, which dipped sharply in 2010-11 due to a strong La Nina event, has recovered and resumed its long-term upward climb. Image credit: NASA/JPL-Caltech/CNES

(Phys.org)—For most of the past two decades, the NASA and European Topex/Poseidon, Jason-1 and Jason-2 satellites have tracked the gradual rise of the world's ocean in response to global warming. In August 2011, scientists at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the University of Colorado in Boulder reported that global sea level rise had hit a speed bump.

The researchers found that between early 2010 and summer 2011, global sea level fell sharply, by about a quarter of an inch, or half a centimeter. Using data from the NASA/German Aerospace Center's Gravity Recovery and (GRACE) spacecraft, they showed that the drop was caused by the very strong La Nina that began in late 2010. This periodic Pacific phenomenon changed all over our planet, moving huge amounts of Earth's water from the ocean to the continents, primarily to Australia, northern South America and Southeast Asia.

Now, a new paper published recently in the journal documents the effects of the 2010-11 La Nina on and updates the measurements. The result: as predicted, by mid-2012, global mean sea level had not only recovered from the more than 0.2 inches (5 millimeters) it dropped in 2010-11, but had resumed its long-term mean annual rise of 0.13 inches (3.2 millimeters) per year. Results of the new study are presented graphically at: http://photojournal.jpl.nasa.gov/catalog/PIA16294 .

"The water the ocean 'lost' was compensated for rather quickly," said lead study author Carmen Boening of JPL. "The newest data clearly indicate that the drop in 2010-11 was only temporary."

JPL co-author Josh Willis added that, like clockwork, the long-term rise of the ocean marches on. "The dip in global sea levels, brought to us courtesy of a major La Nina event, was little more than a pothole in the long road toward a rising ocean and shrinking coastlines," he said.

"In 2011, we detected a lot of water that was temporarily stored over land, causing severe flooding in some regions," said JPL co-author Felix Landerer. "In 2012, we have seen much of this water find its way back into the ocean."

Explore further: New signs of eruption at Iceland volcano

More information: For more information on NASA's satellite altimetry missions, visit: sealevel.jpl.nasa.gov/ . For more on GRACE, visit: www.csr.utexas.edu/grace/ .

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User comments : 26

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Mayday
3.9 / 5 (14) Nov 20, 2012
It is essential to note that the 3mm annual rise has been going on at a remarkably steady rate with remarkably small fluctuations for more than 9,000 years.
mrtea
2.7 / 5 (12) Nov 20, 2012
Not sure what your point is - AGW is accelerating the rise, which will no doubt be catastrophic for many coastal communities (where most humans live) by the end of this century.

http://www.giss.n...fig1.jpg
Mayday
3.3 / 5 (14) Nov 20, 2012
My point was that a cursory look at the chart seems to indicate something dramatic going on since the early 90s. I think it's important to appreciate that that just isn't so. Bad times may lie ahead, but the sea level rise has not yet shown evidence of the coming calamity. And I might add that the gradual nature of the indicated rise allows any prudent individual ample time to prepare.
philw1776
3 / 5 (4) Nov 20, 2012
Prudent individuals do not include Bloomberg et. al. who despite rhetoric left RR trains in yards they were warned would flood and failed to deploy known devices that could block water entry into subway tunnels. I predict even more political hot air about Climate Change but no prudent action such as that done by the Dutch to protect their nation.
Maggnus
4 / 5 (4) Nov 20, 2012
It is essential to note that the 3mm annual rise has been going on at a remarkably steady rate with remarkably small fluctuations for more than 9,000 years.


Can you link to any articles/papers that support this assertation?
Mayday
2.8 / 5 (9) Nov 20, 2012
Maggus: http://en.wikiped...vel_rise

But, with apologies; it has been more like 7,000-7,200 years. But I don't think that dramatically affects the point I was trying to make. Some will disagree. 2,000 years IS a significant typo.
Please search the issue. I'm afraid you'll find wide agreement on the consistent and steady rate of rise.
Mayday
3.2 / 5 (9) Nov 20, 2012
Looking over many charts, you'll notice that it is absolutely vital to define the level of granularity you are attaching to your hypothesis. And of course, each person will choose the granularity that supports their speculations. I certainly do. One could choose to just look back 18 months and conclude that the only sane option is to run for the hills!
Jeddy_Mctedder
2.5 / 5 (11) Nov 20, 2012
no doubt that catastrophe will occur. even if global warming didn't exist. there will always be catastrophe.
VendicarD
4 / 5 (8) Nov 20, 2012
As the following plot shows, the rate of sea level rise has been increasing.

http://www.skepti...el-1.gif

The rate of increase in the late 1800's was roughly 1.6 mm/year

Current rates of rise are over 3mm per year.
VendicarD
3.6 / 5 (9) Nov 20, 2012
The temporary decline in ocean levels was proclaimed by various denialists who post here as solid proof that the ice caps and the worlds glaciers were not melting.

They were told on multiple occasions that the temporary decline was principally caused by large quantities of rain over Australia - which caused massive flooding.

The denialists ignored the science and continued to lie about the reduction anyhow.

Public execution is the only fitting punishment for their crimes against nature and humanity.
Mayday
2.1 / 5 (7) Nov 20, 2012
I'm no denialist, far from it. but I can't see how anyone could look at that tiny window of recent data and see it at odds with the enormous and dramatic rate of sea level rise over the last 18,000 years. On the contrary, if the rise were to slow at all -- now that would be news!
VendicarD
3.2 / 5 (6) Nov 20, 2012
18,000 years ago the earth was still covered by glaciers several miles thick. Hence the lower sea level.

http://upload.wik...evel.png

"dramatic rate of sea level rise over the last 18,000 years." - MayDay

Poor MayDay. He thinks he has made some point, but in fact he has only made himself look childishly foolish.

Judgeking
3 / 5 (6) Nov 21, 2012
According to the graph, sea level is rising 1 inch every 10 years. So it will take 120 years for a 1 foot rise. Seems like plenty of time to act to me, especially since our 'contributions' to global warming have only been going on 200 years at best.
StarGazer2011
1.5 / 5 (8) Nov 21, 2012
Not sure what your point is - AGW is accelerating the rise, which will no doubt be catastrophic for many coastal communities (where most humans live) by the end of this century.

http://www.giss.n...fig1.jpg


Your link shows the exact opposite! IT shows current sea level rise as tiny compared to past rises.
kochevnik
2.7 / 5 (6) Nov 21, 2012
The last messiah was born in the age of the fish under Pisces. The new messiah newborn among us is a water-bearing god under Aquarius. Kevin Costner in Waterworld could be god.
My point was that a cursory look at the chart seems to indicate something dramatic going on since the early 90s.
Just when Waterworld released! There are no coincidences!
It is essential to note that the 3mm annual rise has been going on at a remarkably steady rate with remarkably small fluctuations for more than 9,000 years.
That would put many archeological sites from the time under water.
StarGazer2011
2.1 / 5 (7) Nov 21, 2012
The temporary decline in ocean levels was proclaimed by various denialists who post here as solid proof that the ice caps and the worlds glaciers were not melting.

They were told on multiple occasions that the temporary decline was principally caused by large quantities of rain over Australia - which caused massive flooding.

The denialists ignored the science and continued to lie about the reduction anyhow.

Public execution is the only fitting punishment for their crimes against nature and humanity.


Seriously execution?
We live in a free democratic society.
If your ideas are so strong, why are you losing so badly? Why aren't the Green party in power?
Is it possible that rather than being in the top 30% of IQ because you 'accept the science', you are actually in the bottom 30% by IQ because you 'believe politicians and the TV'?
Its also worth noting that 'climate scientists' predicted permanent drought in AUS, until falsified by the floods, then they changed their story.
Egleton
2 / 5 (4) Nov 21, 2012
Please, Mr Darwin, Please come and rid me of these fools.
9 Billion Darwin Awards!!
Oh Happy day.
TheKnowItAll
2.1 / 5 (7) Nov 21, 2012
It will take thousands of years to melt the rest of the ice no matter what we do it will happen as it is a natural cycle of the earth, and it won't be the end of the world. Also there are a multitude of factors other than the CO2 level which affect the sea level such as the shifting of tectonic plates, underground water reserves, marine ecosystems and solar cycles and so on and so on. Besides, judging from the rate at which technology is advancing I wouldn't lose sleep over this. It just annoys me to see a study done in such a narrow minded way; it makes me wonder what the reasons behind it are. Is it Monetary, Paranoia, Boredom, religious in nature or Low IQ? Which one? Help me chose an option lol
Howhot
3.5 / 5 (6) Nov 21, 2012
It will take thousands of years to melt the rest of the ice no matter what we do


No it won't. It will only take a few decades or less.

it will happen as it is a natural cycle of the earth, and it won't be the end of the world.


Another non-scientist trying to make a scientific claim. No, it will be man-made CO2 global warming (Anthropogenic) that causes the ice-caps to melt. What dumb ass school did you go to?
VendicarD
3.4 / 5 (5) Nov 22, 2012
"It will take thousands of years to melt the rest of the ice no matter what we do it will happen as it is a natural cycle of the earth" - KnowNothingAtAll

Astonishing that the denialist claims that the melting of the polar ice caps is a natural cycle when they are melting at a time when the true natural cycle would be expanding them in the transition to the next ice age.

Here is an interesting graphic...

https://docs.goog...4dUgzdVE

Note the natural "cycle" of cooling temps followed by the unnatural non-cycle of anthropogenic warming.
VendicarD
3 / 5 (4) Nov 22, 2012
Inevitable execution for crimes against nature and man.

"Seriously execution?" - StarGazer

"We live in a free democratic society." - StarGazer

Is that what fools call the current corporate cleptocracy these days?

"If your ideas are so strong, why are you losing so badly?" - StarGazer

Lemmings.

VendicarD
3 / 5 (4) Nov 22, 2012
Poor StarTard. He presents the rise in ocean levels as the earth ended it's last period of glaciation as if it is in any way similar to the current ongoing rise during an industrial period, outside of a period of glaciation that is resulting from the melting of the polar ice caps, and the thermal expansion of ocean water.

"IT shows current sea level rise as tiny compared to past rises." - StarTard

There is really no material difference between criminal insanity and criminal stupidity.

VendicarD
3 / 5 (4) Nov 22, 2012
Best estimates are 1m over the next 100 years or so.

Where do you intend to put the 161 million people currently living in Bangladeshe who will be displaced due to that rise in ocean level?

Do you have a spare bedroom to offer?

"So it will take 120 years for a 1 foot rise." - JudgeJudy
Lurker2358
2 / 5 (8) Nov 23, 2012
It will take thousands of years to melt the rest of the ice no matter what we do it will happen as it is a natural cycle of the earth.


The rate of melting is non-linear, which means it accelerates, and the rate of acceleration is itself accelerating. Over the period of several hundreds to perhaps a few thousand years, this acceleration is limited primarily by the curvature of the Earth and it's maximum potential change in albedo.

As far as I can tell, the rate of melting should keep increasing right up until Greenland is totally melted, and then the excess heat budget afterwards will be transported to the Southern Hemisphere, where it will accelerate the melting of Antarctica that much faster.

Some parts of the N.H. will likely gain an additional month or two worth of annual melting days in the next 50 years alone.

it won't be the end of the world.


Bubonic Plague and the Spanish Flu weren't the "end of the world" either. Would anyone like to repeat them? Hardly.
Lurker2358
2 / 5 (8) Nov 23, 2012
Now if you want to know how important a change of 1 additional average annual melting day is in GW, it's about as important in the short term as a turnover is in football or basketball...which is to say in football a turnover makes as much as a 14 point difference in the final score...

...except in GW an extra melting day sticks with you each year and keeps adding to the score...

So if you're gaining 1 average annual melting day per year, as most of the NH above 60N is doing for the past few decades, then it doesn't take long to add up...

1
2
3
4
5
6
7
8
9
10

Sum that and you get 55 total extra melting days in a 10 year period, or a little over half of one entire winter lost, but it gets worse, because the next 10 years are thrice as bad.

11
12
13
14
15
16
17
18
19
20

Sum of that is 155 additional total melting days gained in a 10 year period, or roughly two whole winters lost.

Not only is an extra melting day equal to extra ice you lose, it's also ice you didn't gain back!
PinkElephant
3.7 / 5 (3) Nov 24, 2012
@Mayday,
It is essential to note that the 3mm annual rise has been going on at a remarkably steady rate with remarkably small fluctuations for more than 9,000 years.
Assuming this is the chart you were focusing on:

http://en.wikiped...evel.png

Then let's do some simple math. At a steady 3 mm per year, you get 3 m rise per millennium. Over 9,000 years that would total up to 27 m. Over your later-corrected 7,000 years, that's still 21 m. Now glance back at that chart. It shows ~3 m over the last 7,000 years. That makes your assertion of "steady" inaccurate by about a factor of 7x.

So, with the above highly complex calculus in mind, could you please explain one more time what point you were trying to make? Much obliged...