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Sea Level Dropped 2010-2011 due to Australia


EdEarl

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A newly published study details how three atmospheric patterns came together in 2010 and 2011, driving so much precipitation over Australia that the world’s ocean levels dropped measurably.

Unusual weather caused flooding in Australia in 2010 and 2011, and the water was soaked up by the dry soil. As a result, the sea level dropped a bit, but since then it has continued to rise by 10 mm (0.4 inches) a year, which is an increase from rising 0.13 inches per year previously.

 

 

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Are you aware of any general trends in sea levels around the world, Ed, seeing your post made me ponder the question of what is happening - only generallly speaking - out there?

Yes, sea levels are rising everywhere because the oceans are a single body of water, and as glaciers melt in mountains, on Greenland, and Antarctica the sea is rising.

 

http://en.wikipedia.org/wiki/Current_sea_level_rise

http://ocean.nationalgeographic.com/ocean/critical-issues-sea-level-rise/

http://oceanservice.noaa.gov/education/pd/climate/factsheets/issea.pdf

http://www.nasa.gov/topics/earth/features/glacier-sea-rise.html

 

ABC news:

TED Talk:

 

and many more

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Although this is from Nov. 2008 it is an interesting NASA article on ocean levels and the difficulties that are confounding the researchers.

http://earthobservatory.nasa.gov/Features/OceanCooling/

 

Quote: The two main causes of sea level rise are melting of Earth’s frozen landscapes—ice sheets, ice caps, and glaciers—and thermal expansion. Water expands when it absorbs heat. If you add the amount of thermal expansion to the amount of melting, it should equal the observed sea level rise, but somehow, it never did.

 

Here's another,

What we found was that ocean heating was larger than scientists previously thought, and so the contribution of thermal expansion to sea level rise was actually 50 percent larger than previous estimates.”

 

So they know what these input values are, but the sea level rise is 50% higher than estimates would suggest.

 

The ocean expansion is what is being observed. It does not equal the rise when added to the melt.

And one more.

“In this analysis, we focused on 1961-2003 because it is the time period highlighted as being an important, unresolved issue in the last IPCC report [intergovernmental Panel on Climate Change Fourth Assessment Report],” said Domingues, “but also because the problems with the newest Argo data—the problems that Josh Willis found as well as other problems we have identified—haven’t been totally solved. For the most recent years [2003-2007], the sea level budget once again does not close. Our team is still working on that problem.”

 

“One thing we found was that climate models that do not include volcanic forcing tend to overestimate the long-term change, and their simulated decadal variability is not in agreement with the observations. On the other hand, the models that include volcanic forcing are more realistic in terms of decadal variability, but they tend to slightly underestimate the long-term warming,” she says. “This kind of result tells us volcanic forcing is important, but that we don’t totally understand it yet.”

 

"Over estimate" and "is not in agreement" vs "more realistic and slightly underestimates".

 

Hmmmm. Maybe the deep ocean has another heat source.

 

The article is worth reading.

 

Here's something else that is related;

ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat05.pdf Warming of the world ocean, 1955–2003
S. Levitus, J. Antonov, and T. Boyer
National Oceanographic Data Center, NOAA, Silver Spring, Maryland, USA
Received 22 September 2004; revised 24 November 2004; accepted 8 December 2004; published 22 January 2005.
Thus, a mean temperature change of 0.1 C. of the world ocean would correspond roughly to a mean temperature change of 100 C. of the global atmosphere if all the heat associated with this ocean anomaly was instantaneously transferred from the ocean to the atmosphere. This of course will not happen but this computation illustrates the enormous heat capacity of the ocean versus the atmosphere.

 

Wow, the ocean looks like it is the dominant thermal content around here. Except for that it is 1/22,000 thousandths of the terrestrial mass of the Earth.

 

So using the NOAA example above, what would a similar 0.1 C mean change in the Earth's volumetric heat capacity (VHC) do to the ocean? Make it phase change into something like Venus?

 

So this unaccounted 50% expansion in the deep ocean could be a vary vary vary small natural variation in the Earth's VHC manifesting through ocean hydro-thermal and volcanic systems. happy.png

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Only the surface of the Earth's land mass is affected by Solar radiation, the interior temperature of the Earth is determined by processes in the core.

 

Ground temperature as a function of season, location and depth is given here. The geothermal gradient is explained here.

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Only the surface of the Earth's land mass is affected by Solar radiation, the interior temperature of the Earth is determined by processes in the core.

 

Ed, your Wikipedia link states 45 - 90% is the result of radioactive decay in the crust.

Much of the heat is created by decay of naturally radioactive elements. An estimated 45 to 90 percent of the heat escaping from the Earth originates from radioactive decay of elements concentrated in the crust.

 

I think this is a pretty reliable link. smile.png

http://newscenter.lbl.gov/news-releases/2011/07/17/kamland-geoneutrinos/

 

This article is about the Kamioka Liquid-scintillator Antineutrino Detector (KamLAND), and states, of the 44 trillion watts of heat that continually flows from Earth's interior into space, 50 percent of the heat is due to radioactive decay and other sources, and primordial heat left over from the planet's formation must account for the rest.

 

The research says radioactive decay of uranium, thorium, and potassium in Earth's crust and mantle is a principal source of the 20+ trillion watts. But where does the other slightly more than half come from.

 

Stuart Freedman who is a member of Berkeley Lab's Nuclear Science Division and a professor in the Department of Physics at the University of California at Berkeley and who is also leading the participation of the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), says in the article; "One thing we can say with near certainty is that radioactive decay alone is not enough to account for Earth's heat energy". "Whether the rest is primordial heat or comes from some other source is an unanswered question."

 

"All models of the inner Earth depend on indirect evidence. Leading models of the kind known as bulk silicate Earth (BSE) assume that the mantle and crust contain only lithophiles (”rock-loving” elements) and the core contains only siderophiles (elements that “like to be with iron”). Thus all the heat from radioactive decay comes from the crust and mantle – about eight terawatts from uranium 238 (238U), another eight terawatts from thorium 232 (232Th), and four terawatts from potassium 40 (40K)."

 

Ed, the other "unaccounted" half is undetermined. It could be any of the following from your link or maybe something else not yet understood. eyebrow.gif

 

  • Heat of impact and compression released during the original formation of the Earth by accretion of in-falling meteorites.
  • Heat released as abundant heavy metals (iron, nickel, copper) descended to the Earth's core.
  • Latent heat released as the liquid outer core crystallization at the inner core boundary.
  • Heat may be generated by tidal force on the Earth as it rotates; since rock cannot flow as readily as water it compresses and distorts, generating heat.
  • There has been speculation that nuclear fission might occur.
  • There is no reputable science to suggest that any significant heat may be created by electromagnetic effects of the magnetic fields involved in Earth's magnetic field, as suggested by some contemporary folk theories.

In the http://earthobservatory.nasa.gov/Features/OceanCooling/page1.php article the researchers are stymied by unaccounted ocean temperature variation and it's physical manifestation: ocean expansion.

 

"Although he has “caused a stir” among his colleagues in the past by criticizing models’ inability to simulate how ocean heat storage varies on short-term time scales," he stresses, “I have said from the beginning that the fact that the long-term trends in models and observations do agree so well is what is most important.”

“My point is just that we need to remain open-minded because it may be that it is possible for the ocean to gain heat and lose it more rapidly than we think. There may be other phenomena [similar to El Niño] operating on different time scales that can explain interdecadal increases and decreases,” says Levitus.

 

Interdecadal is short term, literally between decades. That is the same Mr Levitus of the National Oceanographic Data Center, NOAA, Silver Spring, Maryland, USA and the before mentioned mean temperature change of 0.1 C. temp anomaly transfer example.

 

The article states: "We need theories about how the parts of the Earth system are related to each other so that we can make sense of observations. And we need models to help us see into the future".

 

Nobody is considering models unrelated to solar thermal forcing. confused.gif

Edited by arc
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I think this is a pretty reliable link. smile.png

http://newscenter.lb...d-geoneutrinos/

I agree Arc. My post was a reaction to

 

Wow, the ocean looks like it is the dominant thermal content around here. Except for that it is 1/22,000 thousandths of the terrestrial mass of the Earth.

Which seems like you include the entire Earth mass compared to the Oceanic mass. I was only trying to clarify that only the surface of the Earth and soil to a fairly shallow depth is heated by light from the Sun, while the Earth's interior is heated by other sources.

 

According to Wikipedia (I know not an authority) the mean surface temperature of the moon at the equator is supposed to be -53.15 C (-63.67 F); thus, perhaps some of the interior heat from the Earth may affect Surface temperature, but it would not account for seasonal and daily temperature variations.

 

On the other hand, we know from climate studies that the greenhouse effect is increasing the Earth's temperature; thus, the Earth's surface is warmer than the moon because of its atmosphere.

 

IDK the amount contributed from interior heat vs atmosphere.

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I agree Arc. My post was a reaction to

Which seems like you include the entire Earth mass compared to the Oceanic mass. I was only trying to clarify that only the surface of the Earth and soil to a fairly shallow depth is heated by light from the Sun, while the Earth's interior is heated by other sources.

 

According to Wikipedia (I know not an authority) the mean surface temperature of the moon at the equator is supposed to be -53.15 C (-63.67 F); thus, perhaps some of the interior heat from the Earth may affect Surface temperature, but it would not account for seasonal and daily temperature variations.

 

On the other hand, we know from climate studies that the greenhouse effect is increasing the Earth's temperature; thus, the Earth's surface is warmer than the moon because of its atmosphere.

 

IDK the amount contributed from interior heat vs atmosphere.

 

Ed, sorry about the misunderstanding. My point that I am trying to make on this is whenever I read or hear about ocean levels I know from that NOAA article that there are anomalies in the estimates, especially the short term interdecadal. And as the article shows, these are smoothed out in the adjustments. I just wanted to express a point that most people do not think about. That using the example below can give a person a new perspective.

 

Thus, a mean temperature change of 0.1 C. of the world ocean would correspond roughly to a mean temperature change of 100 C. of the global atmosphere if all the heat associated with this ocean anomaly was instantaneously transferred from the ocean to the atmosphere. This of course will not happen but this computation illustrates the enormous heat capacity of the ocean versus the atmosphere.

 

The atmosphere is a little over a millionth (0.000 001) or 1/1,200,000 of one Earth mass. The ocean is 1/22,000 or 0.022 of one earth mass. These two thermal contents add up to practically nothing when compared to the Earths entire thermal content. Most of the heat content in these two systems is at their boundary with each other. But most of the ocean is actually substantially colder. Deep ocean is just above freezing.

 

While on the other hand the mantle constitutes about 84% of Earth's volume with temperatures that range between 500 to 900 °C (932 to 1,652 °F) at the upper boundary with the crust to over 4,000 °C (7,230 °F) at its inner boundary. Next is the outer core; a billion trillion tons of molten iron that has temperatures estimated between 4400 °C (7952 F.) in the outer regions to 6100 °C (11000 F.) near the inner core, of which may have a temperature as high as the Sun's surface, at around 5430 °C (9806 F.).

 

Taking into consideration the atmosphere and ocean facts that include the mean temperature change example above, one can see that the Earths heat content could erase the ocean and atmosphere without losing a degree of content.

 

So why would we think that the terrestrial Earth with such a massive heat content would not vary infinitesimally in content over time. It would now seem unlikely that it wouldn't. Why would we think that an entire planet, one with a magnetic field generator that varies in output would not produce a small thermal variable? Probably a cycle. How much of a minuscule variation would it take to cause the ocean to expand the unaccounted amount? Easily small enough that it would go unnoticed.

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Arc, I should have quoted the line I was quibbling over. NP, we have improved our posts and understanding of the process.

 

You make a good point. I have no idea how much NOAA knows about undersea volcanos and how they contribute to ocean temperature. I know they used a cold war sonar sensor array, SOund SUrveillance System (SOSUS), to monitor the oceans, and others.

 

Since 1991, NOAA has successfully used these arrays to detect submarine volcanic eruptions in the northeast Pacific and blue whale movements in the same area. The range of the system is such that volcanic tremors from south of Japan have been successfully detected and located using SOSUS arrays deployed off the coasts of Oregon and Washington. Access to SOSUS is restricted, both in the sense that the data are classified and can only be used in a secure facility. The arrays also do not cover the entire world's oceans as they are deployed only in areas of military need. The cabled nature of SOSUS allows real-time acquisition of the acoustic data, but at a high cost; the total investment in SOSUS is estimated at more than $16 billion.

They aren't ignorant of the processes, obviously. I have not heard news reports of exceptional undersea volcanic events, but that is not particularly surprising. Wikipedia says:

 

Scientists still have much to learn about the location and activity of underwater volcanoes. The Kolumbo underwater volcano in the Aegean Sea was discovered in 1650 when it burst from the sea and erupted, killing 70 people on the nearby island of Santorini. More recently, NOAA's Office of Ocean Exploration has funded exploration of submarine volcanoes, with the Ring of Fire missions to the Mariana Arc in the Pacific Ocean being particularly noteworthy. Using Remote Operated Vehicles, scientists studied underwater eruptions, ponds of molten sulfur, black smoker chimneys and even marine life adapted to this deep, hot environment.

 

Many submarine volcanoes are seamounts, typically extinct volcanoes that rise abruptly from a seafloor of 1,000 - 4,000 meters depth. They are defined by oceanographers as independent features that rise to at least 1,000 meters above the seafloor. The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea.[2] An estimated 30,000 seamounts occur across the globe, with only a few having been studied. However, some seamounts are also unusual. For example, while the summits of seamounts are normally hundreds of meters below sea level, the Bowie Seamount in Canada's Pacific waters rises from a depth of about 3,000 meters to within 24 meters of the sea surface.

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Ed, I think this is more simple than even volcanoes. The ocean seems to all of us as an immense body. But as shown previously it is 22 thousand times less then the terrestrial mass. The deep ocean is in direct contact with over 64% of the Earth's crustal surface, this being the ocean crust. These areas have deep penetration by ocean waters. This boundary deep in the crust is where the planets thermal content and the crushing pressures of the deep ocean meet. Water is a hydraulic liquid, a small decadal thermal movement and expansion in this location would produce an immediate surface elevation response.

 

http://earthobservatory.nasa.gov/Features/OceanCooling/

In the past 50 years, sea level rose about 1.8 (plus or minus 0.3) millimeters a year. Satellite observations since 1993 indicate the pace has accelerated to about 3 millimeters per year. What’s driving the acceleration? How much and how fast will sea level rise in the future? In trying to answer these questions, scientists repeatedly tried to balance the sea level budget, and they repeatedly came up short.

 

In the article the sea level budget was corrected but not completely.

 

Since the revision, says Willis, the bumps in the graph have largely disappeared, which means the observations and the models are in much better agreement.

 

Levitus agrees that the interdecadal variability is substantially decreased, but it isn’t totally gone. He argues that before anyone assumes that the observations must be wrong, they should remember that the amount of variability they are talking about is probably less than the amount of heat gained and lost during the intense El Niño in 1997-98. “Climate models don’t reproduce El Niño events very well either,” he says, but no one doubts they are real.

post-88603-0-61430900-1377836870_thumb.png

Original graph (Blue elements) by Robert Simmon, NASA's Goddard Space Flight Center. Red elements by this author.

 

Could Earth's terrestrial thermal content vary in slow interdecadal periodicities? It is now hard to imagine it wouldn't.

Edited by arc
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