The Reef Ain't Dead

[Reefmagnet]

Originally Posted by GordMay

The graph https://www.giss.nasa.gov/research/b...en_15/fig1.gif came from:
“Earth's Climate History: Implications for Tomorrow” ~ by James E. Hansen and Makiko Sato — July 2011
➥ https://www.giss.nasa.gov/research/briefs/hansen_15/

You may want to do a little more reading., including, but not limited to:
“Paleoclimate Implications for Human-Made Climate Change” ~ by James E. Hansen & Makiko Sato [2012]
“... We conclude that Earth in the warmest interglacial periods of the past million years was less than 1°C warmer than in the Holocene. Polar warmth in these interglacials and in the Pliocene does not imply that a substantial cushion remains between today's climate and dangerous warming, but rather that Earth is poised to experience strong amplifying polar feedbacks in response to moderate global warming. Thus goals to limit human-made warming to 2°C are not sufficient — they are prescriptions for disaster. Ice sheet disintegration is nonlinear, spurred by amplifying feedbacks. We suggest that ice sheet mass loss, if warming continues unabated, will be characterized better by a doubling time for mass loss rate than by a linear trend. Satellite gravity data, though too brief to be conclusive, are consistent with a doubling time of 10 years or less, implying the possibility of multi-meter sea level rise this century. Observed accelerating ice sheet mass loss supports our conclusion that Earth's temperature now exceeds the mean Holocene value. Rapid reduction of fossil fuel emissions is required for humanity to succeed in preserving a planet resembling the one on which civilization developed.
➥ https://link.springer.com/chapter/10...-7091-0973-1_2

➥ https://www.giss.nasa.gov/research/news/20111208/

Yeah, maybe so. But it doesn't exactly reinforce the "reef never bleached before 1980" theory.

[BigBeakie]

Reefmagnet;

It correlates via the Milankovitch cycle. You do know what that is, don't you? If not, then there are many, many easy references to learning why the Earth goes through long term cycles of cooling & warming on the timescales your graph illustrate.

The short version is:
1 The orbit of the Earth changes between circular and elliptoid.
2 The tilt of the earth changes.
3 The Earth "wobbles" on its axis.
All of these affect the amount of energy the Earth receives from the Sun.


We are not talking about warming on geological timescales. We are discussing a timescale of a couple of HUNDRED years, and specifically an effect of coral bleaching observed since the 1980's, i.e. 40 years.

Got it?

[BigBeakie]

Raymond;

You have an incorrect concept of how corals grow. Corals ( ie hard corals) lay down a substrate "skeleton" of calcium Carbonate that their tissue uses for support. They lay down this skeleton continuously. As far as we know, they do not die, they are immortal and will keep growing and multiplying when conditions are suitable > available food, available sunlight for the algae, suitable water temperature and composition.

When hard corals bleach from high water temperature, they will die after awhile, after the algae have been ejected. When they die, that's it, they are dead. They do not spring back to life. The white skeleton is left for other species of algae to invade and grow, the green-brown stringy stuff.

It is possible coral larvae may settle on the dead skeleton and start a new colony, but probably won't be the same species that died.

[Reefmagnet]

Originally Posted by BigBeakie

Reefmagnet;

It correlates via the Milankovitch cycle. You do know what that is, don't you? If not, then there are many, many easy references to learning why the Earth goes through long term cycles of cooling & warming on the timescales your graph illustrate.

The short version is:
1 The orbit of the Earth changes between circular and elliptoid.
2 The tilt of the earth changes.
3 The Earth "wobbles" on its axis.
All of these affect the amount of energy the Earth receives from the Sun.


We are not talking about warming on geological timescales. We are discussing a timescale of a couple of HUNDRED years, and specifically an effect of coral bleaching observed since the 1980's, i.e. 40 years.

Got it?

By the sounds of things, I know a lot more than you do.

[BigBeakie]

Originally Posted by Reefmagnet

By the sounds of things, I know a lot more than you do.

Some suggested viewing:

https://www.youtube.com/watch?v=y50i1bI2uN4

https://www.youtube.com/watch?v=pOLmD_WVY-E

[Reefmagnet]

Originally Posted by BigBeakie

Some suggested viewing:

The short version is:
1 The orbit of the Earth changes between circular and elliptoid.
2 The tilt of the earth changes.
3 The Earth "wobbles" on its axis.
All of these affect the amount of energy the Earth receives from the Sun.

Regardless of variation in eccentricity and axial tilt of the Earth's orbit, the total energy received from the Sun falling on the Earth is pretty much the same regardless of these variations over the course of one orbit.

Ok so the GBR is really, really old and the first widespread mass bleaching events are noted in that looooong time span for the first time in the 1980's, and of that the events are somewhat spread out with years between events, but they are getting:
more intense,
are involving more reefs around the world,
are increasing in frequency to the point where now we have 3 events within a 5 year period.....

Based on your statement above, and transferring it to extrasolar planets, it could be stated:

• The universe is really, really old and there were no extrasolar planets noted prior to 1992
• More and more extrasolar planets are appearing, especially smaller ones.
• More and more stars are getting extrasolar planets.
• The frequency of extrasolar planets appearing is rapidly increasing.
• Our solar system can expect additional planets to appear.

Or, perhaps it's simply a case of

"If a tree falls in a forest and no one is around to hear it, does it make a sound?"

[BigBeakie]

"Regardless of variation in eccentricity and axial tilt of the Earth's orbit, the total energy received from the Sun falling on the Earth is pretty much the same regardless of these variations over the course of one orbit."

Sigh....sorry, but "pretty much the same" and "over the course of one orbit" indicates you really don't get it.

At the risk of feeding the trolls and providing basic high school level information, please note the following simplified explanation of the Milankovitch cycle influence on Earths climate cycles and glaciation. Note the timescales involved & how that would relate to "one orbit".

https://climate.nasa.gov/news/2948/m...arths-climate/

[Reefmagnet]

Originally Posted by BigBeakie

"Regardless of variation in eccentricity and axial tilt of the Earth's orbit, the total energy received from the Sun falling on the Earth is pretty much the same regardless of these variations over the course of one orbit."

Sigh....sorry, but "pretty much the same" and "over the course of one orbit" indicates you really don't get it.

At the risk of feeding the trolls and providing basic high school level information, please note the following simplified explanation of the Milankovitch cycle influence on Earths climate cycles and glaciation. Note the timescales involved & how that would relate to "one orbit".

https://climate.nasa.gov/news/2948/m...arths-climate/

It's obvious physics isn't your strong suite.


Let me quote your statement once more...

The short version is:
1 The orbit of the Earth changes between circular and elliptoid.
2 The tilt of the earth changes.
3 The Earth "wobbles" on its axis.
All of these affect the amount of energy the Earth receives from the Sun.

[StuM]

Originally Posted by BigBeakie

g
The short version is:
1 The orbit of the Earth changes between circular and elliptoid.
2 The tilt of the earth changes.
3 The Earth "wobbles" on its axis.
All of these affect the amount of energy the Earth receives from the Sun.

None of those variations affect the mean solar distance.
Ergo they do NOT affect the amount of energy the Earth receives over a year. Earth receives the same annual insolation every year regardless of those oscillations.

The only affect they have is on the relative insolation at various latitudes and the seasonal variations from the mean insolation for those latitudes.




.

[StuM]

Originally Posted by BigBeakie

Sigh....sorry, but "pretty much the same" and "over the course of one orbit" indicates you really don't get it.

No, you clearly don't get it.

At the risk of feeding the trolls and providing basic high school level information, please note the following simplified explanation of the Milankovitch cycle influence on Earths climate cycles and glaciation. Note the timescales involved & how that would relate to "one orbit".

https://climate.nasa.gov/news/2948/m...arths-climate/

So kindly point out where that link suggests that annual insolation varies at all over the timescales involved in the cycles..

The crux of the theory, which you apparently do not understand, is in these quotes:

Milankovitch combined the cycles to create a comprehensive mathematical model for calculating differences in solar radiation at various Earth latitudes along with corresponding surface temperatures. ...Milankovitch assumed changes in radiation at some latitudes and in some seasons are more important than others to the growth and retreat of ice sheets. In addition, it was his belief that obliquity was the most important of the three cycles for climate, because it affects the amount of insolation in Earth’s northern high-latitude regions during summer .

i.e Nothing about changes in total insolation whether over 1 year or over a cycle. just changes in when and where the insolation occurs over a year.

[RaymondR]

Originally Posted by BigBeakie

Raymond;

You have an incorrect concept of how corals grow. Corals ( ie hard corals) lay down a substrate "skeleton" of calcium Carbonate that their tissue uses for support. They lay down this skeleton continuously. As far as we know, they do not die, they are immortal and will keep growing and multiplying when conditions are suitable > available food, available sunlight for the algae, suitable water temperature and composition.

When hard corals bleach from high water temperature, they will die after awhile, after the algae have been ejected. When they die, that's it, they are dead. They do not spring back to life. The white skeleton is left for other species of algae to invade and grow, the green-brown stringy stuff.

It is possible coral larvae may settle on the dead skeleton and start a new colony, but probably won't be the same species that died.

Fully aware that gazillions of polyps get together and excrete a calcium carbonate exoskeleton which turns into a coral reef.

According to Mr Google the polyps don't live forever.

Whilst the polyps may die when subjected to excessive heat this tends to be a transient phenomenon and the barren areas are fairly quickly recolonized by a new spawning.

There was one a few days ago on the reef.

[BigBeakie]

So what is the meaning of this statement in the NASA document?

" These cyclical orbital movements, which became known as the Milankovitch cycles, cause variations of up to 25 percent in the amount of incoming insolation at Earth’s mid-latitudes (the areas of our planet located between about 30 and 60 degrees north and south of the equator).

The Milankovitch cycles include:

The shape of Earth’s orbit, known as eccentricity;
The angle Earth’s axis is tilted with respect to Earth’s orbital plane, known as obliquity; and
The direction Earth’s axis of rotation is pointed, known as precession.

[BigBeakie]

"Fully aware that gazillions of polyps get together and excrete a calcium carbonate exoskeleton which turns into a coral reef.

According to Mr Google the polyps don't live forever.

Whilst the polyps may die when subjected to excessive heat this tends to be a transient phenomenon and the barren areas are fairly quickly recolonized by a new spawning.

OK, they aren't immortal. But some Diploria species are very large, as in 8 meters diameter, and the coral grows perhaps 0.5 cm/yr. So isn't that, like 8,000 years old, maybe more? I was told they may well be the oldest living organisms on Earth.

Well they were, until they died in a bleaching event.......

I think you are confusing the death of the coral polyp (the animal) with the ejection of the of the zooxanthellae ( the plant cell that produces the food for the polyp). The polyp ejects the coloured zooxanthellae during bleaching event, then the exoskeleton is white. IF conditions improve, the polyp colony can be be re-colonized by other zooxanthellae, and continue to live and grow.

But if the period of zooxanthellae ejection goes on for too long, the coral polyp dies. As in dead forever. There are no coral Lazarus's.

Now it's possible the dead exoskeleton can have a coral larva from the spawn resettle on it, and a new colony grows, but as far as I'm aware it is most unlikely it would be by the same species of coral polyp. That would be just chance, and there are over 400 species of coral on the GBR.

More likely the gooey, stringy algae takes over on the exoskeleton, which makes re-settlement of spawn larvae less likely, which is what all those photos of vast areas of brown green algae are.

[Reefmagnet]

Originally Posted by BigBeakie

So what is the meaning of this statement in the NASA document?

" These cyclical orbital movements, which became known as the Milankovitch cycles, cause variations of up to 25 percent in the amount of incoming insolation at Earth’s mid-latitudes (the areas of our planet located between about 30 and 60 degrees north and south of the equator).

The Milankovitch cycles include:

The shape of Earth’s orbit, known as eccentricity;
The angle Earth’s axis is tilted with respect to Earth’s orbital plane, known as obliquity; and
The direction Earth’s axis of rotation is pointed, known as precession.

The variations are caused by Milankovitch cycles, that is true. The variation is relative to any fixed range of latitude because the maximum insolation point (ie when the sun is directly overhead) shifts across latitudes at varying intensity between seasons at different phases of the cycle. Then, depending on the intensity and the geography of the location(s), the theories of positive and negative feedback come into play due to land vs water vs ice vs clouds vs currents vs winds and such.


In all cases, however, the average annual energy striking the Earth from the Sun remains constant because the average distance of the Earth to the Sun doesn't change.

[BigBeakie]

So therefore if what you are saying is true, there is no delta in the solar energy, and therefore there are never any glacial periods and inter- glacial periods, right? It's a steady state, energy wise, right?