Ocean Temps

[Tigertown]

Couldn't find a thread on this;apologies if I missed one.
A while back it was thought that warming had paused, only to find out that the oceans are a great heat sink and in particular, the Indian Ocean had stored 70% of the ocean heat gain. Now, everytime you look at an SST map or anomaly map, it will scare the daylights out of you, if even only you have a basic understanding of how science and weather and climate work together. If nothing else, you know  that the heat along with acidification is killing life off. Coral reefs are probably the most publicized of these. I guess there is need to make mention at least of deadly algae blooms on the rise. Besides all this, my biggest question is: How much more heat can be stored in the waters before it starts heating everything else to an even greater extent. I mean if the oceans have been a buffer up to a point, how bad would it be at the moment had that buffer not been available and how bad will it be without it when it reaches capacity or at least absorbs less heat. 95⁰ F off the coast of Florida in one place a day or two ago making a new record. There have been hot spots all over, especially the S. Pacific. Hardly makes the news until a storm passes through one of these areas and "blows" up into a monster. Enough of my input; I submit now to greater minds.

[Tigertown]

I just ran across this article from 2015.

http://e360.yale.edu/feature/how_long_can_oceans_continue_to_absorb_earths_excess_heat/2860/

[Bruce Steele]

Tigertown, I can't get your Yale /360 article link to load. Maybe you could try it again ?
Because we are a year + down the road from  2015 data I do think some of that heat has moved from the Western pacific oceans back into the atmosphere via our recent El Niño .  Also expect Western Pacific heat to rebuild until the next El Niño , my expectation anyhow.

[johnm33]

This worked for me http://e360.yale.edu/feature/how_long_can_oceans_continue_to_absorb_earths_excess_heat/2860/

[Tigertown]

Thank you johnm33 for fixing that link. I will be on the lookout for more recent research. I have read in the last couple of days that some of this warmer water is ending up in Antarctica via ocean currents and accelerating bottom melt there. As the Yale article said, the heat took years to build up and when and if heat is discharged it will take a long time.

[Tigertown]

Article here focuses mostly on the effects on sea life from oceans warming.


http://news.nationalgeographic.com/2016/09/oceans-warming-global-environment-climate/

[Tigertown]

Well, I promised to look for more updated articles concerning the oceans and heat storage. It's funny how you can google something every imaginable way and it never shows up, but then out of the blue as I was looking for something else;  VOILA!
Found this in a little'o obscure newspaper called the New York Times. That's probably why it was so hard to find.

www.nytimes.com/interactive/2016/09/12/science/earth/ocean-warming-climate-change.html?_r=0

If you want something deeper, her is where the NYT's got their info.

https://portals.iucn.org/library/sites/library/files/documents/2016-046_0.pdf

[Tigertown]

Introduction to Argo.

 

[Tigertown]

https://www.theguardian.com/environment/climate-consensus-97-per-cent/2017/mar/10/earths-oceans-are-warming-13-faster-than-thought-and-accelerating

It is these changes that affect storms, such as the deluges that have recently affected California, or which have led storms to produce “thousand year floods” as has been seen in the Carolinas with Hurricane Matthew, or the Louisiana floods in August last year, or the Houston floods in April, and so forth. This kind of knowledge and understanding has profound consequences.

[nicibiene]

Thank you, @Tigertown. The Guardian seems to be the only journal where to find news of that kind... Yesterday evening I found that only a few german papers picked the incredible CO2 denial of Priutt, and none of the few publications offered the opportunity to leave a comment or start a discussion.

Usually I like to grab into that discussions. Always nice to get some other hints when reading comments:

`In fact, the climate models underestimated the rate of sea level rise because the rapid melting of the ice sheets and glaciers was not incorporated in the last IPCC report. (It was left out because the data were not considered sufficiently robust).`
Astonishing !

[gerontocrat]

This is how I look at AGW.

 One can look at an el nino as the oceans burping out some of the excess stored heat which can then radiate out into space. A la nina can then be seen as accelerating heating of the biosphere - cool SSTs mean greater heat transfer from the atmosphere into longterm storage in the oceans. i.e. warming of the atmosphere is largely a side-effect of ocean heating.

Loss of sea ice exaggerates the effect on Arctic atmospheric temperatures, leadiing to positive feedback being even more heat captured by the oceans.

This new report on ocean heating is fairly disastrous. I guess we have to wait for the climate modellers to plug the data in.

[Cate]

Robert weighs in on that report about ocean heating here:

https://robertscribbler.com/2017/03/10/the-oceans-are-warming-faster-than-previously-though-rate-of-heat-build-up-is-accelerating/

[Tigertown]

Another RS article that applies here.
The Glowing Waters of the Arabian Sea are Killing off Ocean Life

https://robertscribbler.com/2017/03/19/the-glowing-waters-of-the-arabian-sea-are-killing-off-ocean-life/

But the human-caused climate change that is spurring the massive noctiluca blooms in the Arabian Sea is bringing on these new conditions over the mere course of a few decades.     

 The oceans beneath the noctiluca mats are now increasingly robbed of life. Oxygen levels are plummeting.

[nicibiene]

http://bigstory.ap.org/article/39cdba54f35548ffb0914094343bb0c6/growing-algae-bloom-arabian-sea-tied-climate-change 

The satellite technology has enabled scientists to link the algae to higher levels of air and water pollution in recent decades, but Bontempi said questions remain. "We know that our Earth is changing," she said. "It may be in a direction we might not like."

Scientists based at the Lamont-Doherty Earth Observatory at Columbia University trace Oman's blooms to melting ice in the Himalayas. Less ice has raised temperatures in South Asia and strengthened the Indian Ocean's southwest monsoon. As this weather front moves across the Arabian Sea every year, it churned up oxygen-poor water thick with nutrients that have fueled the rise of a 1.2-billion-year old algae called noctiluca scintillans.  [\quote]

[Tigertown]

A little area of water just south of Hainan, China seems to be the warmest ocean water in the world at this moment, at 31.8^oC. There are some other hot spots very nearby, though.

https://earth.nullschool.net/#current/ocean/primary/waves/overlay=sea_surface_temp/orthographic=-241.78,19.04,620/loc=109.963,17.377

Or not.

https://earth.nullschool.net/#current/ocean/primary/waves/overlay=sea_surface_temp/orthographic=-308.96,26.21,620/loc=58.681,24.432

[Forest Dweller]

Here is an article referencing study into kelp forests:
http://theconversation.com/underwater-health-check-shows-kelp-forests-are-declining-around-the-world-68569

[Tigertown]

There are positive SST anomalies all over. Some off the East coast of North america are as high as 7^oC and up. You can also see some negative ones that probably were caused by melting ice. The area below Greenland where the cold and warm waters meet seems to be the birthplace of a good many storms.

[wili]

https://www.theguardian.com/environment/climate-consensus-97-per-cent/2017/jun/26/new-study-confirms-the-oceans-are-warming-rapidly

New study confirms the oceans are warming rapidly

Although there’s some uncertainty in the distribution among Earth’s ocean basins, there’s no question that the ocean is heating rapidly

[oren]

 Intereting article. It sheds light on the 1940s warming that always seemed to me like some strange war-related artefact.

In the paper, we describe perhaps the three most important factors that affect ocean-temperature accuracy. First, sensors can have biases (they can be “hot” or “cold”), and these biases can change over time. An example of biases was identified in the 1940s. Then, many ocean temperature measurements were made using buckets that gathered water from ships. Sensors put into the buckets would give the water temperature. Then, a new temperature sensing approach started to come online where temperatures were measured using ship hull-based sensors at engine intake ports. It turns out that bucket measurements are slightly cooler than measurements made using hull sensors, which are closer to the engine of the ship.

During World War II, the British Navy cut back on its measurements (using buckets) and the US Navy expanded its measurements (using hull sensors); consequently, a sharp warming in oceans was seen in the data. But this warming was an artifact of the change from buckets to hull sensors. After the war, when the British fleet re-expanded its bucket measurements, the ocean temperatures seemed to fall a bit. Again, this was an artifact from the data collection. Other such biases and artifacts arose throughout the years as oceanographers have updated measurement equipment. If you want the true rate of ocean temperature change, you have to remove these biases.

[Bruce Steele]

The water temperature at Red Dog dock, Kotzebue Sound has continued to rise. It hit 47.8F today which is higher than water temperatures at Nome. The water temperatures at Red Dog dock have risen by more than 17 degrees in less than two days. Air temperatures hit 60 degrees.

http://www.ndbc.noaa.gov/station_page.php?station=RDDA2

[gerontocrat]

Thought I would revive this topic as the internet on my mobile phone showed that https://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ had updated the global heat content graphs to December 2017, showing the continuing strong upward trend, and reversing the downward blip

But lo and behold, on my PC the same website only has data to September 2017. Ho hum, try later.

[gerontocrat]

Despite not having the latest quarter's data from NOAA's NODC on Global Ocean Heat Content, I've been thinking. (Sorry)

There was a recent study in nature saying that the atmospheric response to increasing CO2 might be less prone to violent change than thought.

Thinks I, what about the oceans ? Ignored again ?

The oceans as a whole have a capacity as a heat sink some 1,000+ times that of the atmosphere.
The oceans per cubic metre have a capacity as a heat sink some 3,000+ times that of a cubic metre of atmosphere.

The oceans have been absorbing vast amounts of heat, which if released all at once (which they will not, of course) raise atmospheric temperatures to well over disaster level.

My guess is that it will be ocean heat that finally does for Arctic Sea Ice and major destruction of large parts of the Greenland and Antarctic ice sheets from below.

The oceans increased capture of excess energy seems to match the increase in CO2 ppm well, I cannot find anything on google which talks about any correlation between CO2 ppm and increasing heat in the oceans.

BUT it still seems the global warming debate is captured by the atmosphere.

- END OF COMPLAINT -

attached:- some environmental arithmetic,
Global Ocean Heat Content image
Mauna Loa graph

[gerontocrat]

PS: To get a better idea of the energy acquired by the oceans in recent years:-

ENERGY ACQUIRED BY OCEANS SINCE ABOUT 1985 in Joules            
Depth 0 to 700 metres   1.5E+23 = 41,667,000,000 Gigawatt hours   
Depth 0 to 2000 metres   2.3E+23 = 63,889,000,000 Gigawatt hours

Eon Musk's mega battery's capacity in S. Australia is 100 Megawatt hours.

[Sleepy]

2017 was the warmest year on record for the global ocean, according to an updated ocean analysis from Institute of Atmospheric Physics/Chinese Academy of Science (IAP/CAS).

https://phys.org/news/2018-01-warmest-year-global-ocean.html

[Bernard]

PS: To get a better idea of the energy acquired by the oceans in recent years:-

ENERGY ACQUIRED BY OCEANS SINCE ABOUT 1985 in Joules            
Depth 0 to 700 metres   1.5E+23 = 41,667,000,000 Gigawatt hours   
Depth 0 to 2000 metres   2.3E+23 = 63,889,000,000 Gigawatt hours

Eon Musk's mega battery's capacity in S. Australia is 100 Megawatt hours.

Also to compare with the Total Primary Energy Supply, a measure of worldwide human production/consumption of energy, all sources added. For 2013, according to WP, it was 1.575E+17 Wh, or 1.575E+8 GWh.
The above figure represent, for each year, more than 10 times the TPES (correct me if I am wrong).
https://en.wikipedia.org/wiki/World_energy_consumption

[gerontocrat]

Also to compare with the Total Primary Energy Supply, a measure of worldwide human production/consumption of energy, all sources added. For 2013, according to WP, it was 1.575E+17 Wh, or 1.575E+8 GWh.
The above figure represent, for each year, more than 10 times the TPES (correct me if I am wrong).
https://en.wikipedia.org/wiki/World_energy_consumption

Hullo Bernard, you beat me to it. By the time I thought about it I was in the pub. (table below)

Also all that additional heat has over the last 30 years raised the temperature of the oceans (average 0 to 2000 metres) by a staggering (?) 0.1 degree centigrade. (See graphs)

The next thing I fancy a look at is a comparison with energy used to melt sea ice. That should be interesting. It is all to get a handle on the context of all the data flying around.

[Bernard]

By the time I thought about it I was in the pub.

Ha! Happy to see my own computation was correct 

Meanwhile, I made another impressive one over my coffee. Given that the fusion enthalpy of ice is 333.55 J/g, 2.3E+23 J is potentially able to melt (at 0°C) 6.9E+14 tons of ice, representing about 7.7E+14 m³, or 770,000 km³ of ice. This represents a layer of about 360m thick if spread over Greenland. Or a significant 3% of the total volume of ice in Antarctica.

[gerontocrat]

By the time I thought about it I was in the pub.

Ha! Happy to see my own computation was correct 

Meanwhile, I made another impressive one over my coffee. Given that the fusion enthalpy of ice is 333.55 J/g, 2.3E+23 J is potentially able to melt (at 0°C) 6.9E+14 tons of ice, representing about 7.7E+14 m³, or 770,000 km³ of ice. This represents a layer of about 360m thick if spread over Greenland. Or a significant 3% of the total volume of ice in Antarctica.

Show off !

My random thought is that by burning fossil fuels to produce an amount of energy somewhat less than total energy production (to produce CO2) this allows at least 10 times that amount of energy to be captured by the oceans. How efficient is that! Isn't mankind clever ! A pity the energy is not really useable by mankind.

[Lord M Vader]

NOAA has updated the OHC data for the reminder of 2017. As is clearly seen, the heat release during the last El Niño has regained and is now higher than it was before El Niño 2014-2016.

[Bernard]

Show off !

Jealous !
I must confess I got a little help from an old friend
http://www.datamath.org/Sci/Galaxy/TI67Galaxy.htm
25 years old, never changed the battery 

[gerontocrat]

Show off !

Jealous !
I must confess I got a little help from an old friend
http://www.datamath.org/Sci/Galaxy/TI67Galaxy.htm
25 years old, never changed the battery 

Blasted scientists. Have you a slide rule hiding somewhere as well ?

LAST COMPARISON (I think)
COMPARING GLOBAL OCEAN HEAT CONTENT ANNUAL GAIN 1985 to 2017 WITH ENERGY USED IN ANNUAL ARCTIC SEA ICE MELT -

background - quoted from Polar Science Center- PIOMAS Arctic Sea Ice Volume Reanalysis
                    http://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/

ARCTIC SEA ICE ONLY

It takes energy to melt sea ice. How much energy? The energy required to melt the 16,400 Km3 of ice that are lost every year (1979-2010 average) from April to September as part of the natural annual cycle is about 5 x 10^21 Joules.

To melt the additional 280 km3 of sea ice, the amount we have have been losing on an annual basis based on PIOMAS calculations, it takes roughly 8.6 x 10^19 Joules.

Comparing this with annual average ocean heat gain (which is less than the current rate) produces the following results :-

RATIO OF AVERAGE ANNUAL OCEAN HEAT GAIN  TO ENERGY USED IN ANNUAL ICE MELT MARCH TO SEPT      
- 0 to 700 metres   1   
- 0 to 2000 metres   2   

RATIO OF AVERAGE ANNUAL OCEAN HEAT GAIN  TO ENERGY USED FOR ANNUAL  PERMANENT ICE LOSS       
- 0 to 700 metres   58   
- 0 to 2000 metres   89   

It is just as well not a lot of that heat gain ends up in the Arctic. Mind you, new research (often picked up by and explained by AbruptSLR) suggests that the attack of increased ocean temperatures at depth on the underside of ice shelves and glaciers at both ends of the earth is accelerating.

[Bernard]

@gerontocrat

I surrender 

The last figures you give are indeed the most interesting. It shows pretty well that the heat stored in the oceans is a time bomb which has only released a small part of its terrible potential.

As for your mean frontal attack on poor scientists 
- Although I had a quite solid scientific background, I never qualified as a "true" scientist. I taught maths during twenty years (that's not science, right?) and ended up in so-called "knowledge technologies" and "data science" (which is barely a science, either).
- But yes, I have not one, but three rule sliders (mine, my father's, and my brother's). I used them to illustrate to my students the beauty of logarithms. And will pass them to my son, who is a "true" scientist (working currently on Titan's atmosphere). Sadly I get rid of my log tables long ago.

[Bernard]

@gerontocrat

Thinking twice ... I don't surrender yet 

Of course the first thing that comes to mind is that oceans heat will help melting the sea ice, but as you mention it in your bottom line (no pun intended) warmer oceans mean also more efficient bottom melting of floating ice shelves and glaciers, and more efficient transport of latent heat through more humid atmosphere. So, the heat used to melt land ice from both Greenland and Antarctica is probably transferred more through oceans than atmosphere (just a wild guess at that point, I welcome papers about this).
Hence yet another comparison. According to https://climate.nasa.gov/vital-signs/land-ice/, the land ice lost (Greenland + Antarctica) is currently roughly 400Gt/year. With the same computation rules as above, the corresponding melting enthalpy is about 1.3E+20 Joules, a figure of similar magnitude as the one you provide for sea ice, with similar conclusions (the time bomb is just mostly ticking).

[Sigmetnow]

That “methane bomb” from rising ocean temps may have a hidden defuser.  At least for now.

Well, At Least One Catastrophic Climate Scenario Is Looking Less Likely

There’s been loads of media hype regarding the Arctic “methane bomb,” an idea that rising temperatures could cause a pulse of ancient methane, locked in permafrost and frozen hydrates on the ocean floor, to escape to the atmosphere, triggering catastrophic global warming. Well, we have some positive news for you: a new study finds little evidence to support this scenario playing out in at least one fast-warming part of the world.

The study, published this week in Science Advances, used a new radiocarbon analysis technique to parse out how much marine methane is from ancient sources versus more modern sources along a stretch of Alaska’s Beaufort Sea coastline. The authors found that ancient carbon—likely derived from methane hydrates and permafrost at the ocean floor—is indeed being released as methane into deep waters on this rapidly warming continental shelf. But those ancient sources don’t account for much of the methane near the surface, the stuff that could be making its way into the atmosphere.

The study didn’t directly investigate why, but the authors suspect seafloor methane could be getting broken down by ocean microbes before reaching surface waters. ...

https://earther.com/well-at-least-one-catastrophic-climate-scenario-is-loo-1822191077

[gerontocrat]

That “methane bomb” from rising ocean temps may have a hidden defuser.  At least for now.

Well, At Least One Catastrophic Climate Scenario Is Looking Less Likely

There’s been loads of media hype regarding the Arctic “methane bomb,” an idea that rising temperatures could cause a pulse of ancient methane, locked in permafrost and frozen hydrates on the ocean floor, to escape to the atmosphere, triggering catastrophic global warming. Well, we have some positive news for you: a new study finds little evidence to support this scenario playing out in at least one fast-warming part of the world.

The study, published this week in Science Advances, used a new radiocarbon analysis technique to parse out how much marine methane is from ancient sources versus more modern sources along a stretch of Alaska’s Beaufort Sea coastline. The authors found that ancient carbon—likely derived from methane hydrates and permafrost at the ocean floor—is indeed being released as methane into deep waters on this rapidly warming continental shelf. But those ancient sources don’t account for much of the methane near the surface, the stuff that could be making its way into the atmosphere.

The study didn’t directly investigate why, but the authors suspect seafloor methane could be getting broken down by ocean microbes before reaching surface waters. ...

https://earther.com/well-at-least-one-catastrophic-climate-scenario-is-loo-1822191077

Hullo Sigmetnow,

I think the people who did this study were looking for the bomb in the wrong place, i.e. great science looking at the wrong sample. On this forum there has been extensive debate about methane in : Forum » Cryosphere » Permafrost » Arctic Methane Release.

It is the Eastern Siberian Arctic Shelf (ESAS), a huge area of very shallow seas, that is much more likely to be the villain.

A-Team posted some super stuff on the thread from which I also include a quote. See :

https://forum.arctic-sea-ice.net/index.php/topic,12.msg133978.html#msg133978

The ESAS, especially the near-coastal regions rich in methanogenic sediment, is exceedingly shallow, much of it less than 10 m deep. Again, it's baffling why people keep referring to deep sea methane studies or inconsequential shelf areas like the Beaufort with very different histories. Sure, those bubbles will get swept aside by currents and dissolve in sea water, eventually getting metabolized before Henry's Law kicks in.

That isn't the case for over-pressurized methane in shallow water because high volume hotspot vents physically entrain seawater, bringing the methane rapidly near and to the surface where it can equilibrate with (ie raise) the currently low partial pressure of atmospheric methane.

In the interview, Shakhova says "a fraction" will inevitably reach the atmosphere, not specifying that fraction other than to say given the immense estimated methane reserves, its pressure, the erosion of permafrost lid, and beyond-linear rate of hotspot development, that this fraction is all that it would take to seriously disrupt global climate.

[SteveMDFP]

It is the Eastern Siberian Arctic Shelf (ESAS), a huge area of very shallow seas, that is much more likely to be the villain.

A-Team posted some super stuff on the thread from which I also include a quote. See :

https://forum.arctic-sea-ice.net/index.php/topic,12.msg133978.html#msg133978

The ESAS, especially the near-coastal regions rich in methanogenic sediment, is exceedingly shallow, much of it less than 10 m deep. Again, it's baffling why people keep referring to deep sea methane studies or inconsequential shelf areas like the Beaufort with very different histories. Sure, those bubbles will get swept aside by currents and dissolve in sea water, eventually getting metabolized before Henry's Law kicks in.

That isn't the case for over-pressurized methane in shallow water because high volume hotspot vents physically entrain seawater, bringing the methane rapidly near and to the surface where it can equilibrate with (ie raise) the currently low partial pressure of atmospheric methane.

In the interview, Shakhova says "a fraction" will inevitably reach the atmosphere, not specifying that fraction other than to say given the immense estimated methane reserves, its pressure, the erosion of permafrost lid, and beyond-linear rate of hotspot development, that this fraction is all that it would take to seriously disrupt global climate.

Quite right.  It's not just that deep methane seeps have farther to go to reach the ocean surface, thus more time for microbes to metabolize them.  Far more important is the *solubility* of methane in water.  At atmospheric pressure, methane is highly insoluble in water.  However, in the great pressures at depth, methane is moderately soluble in water.  Depth and pressure are massively important in determining whether methane from seeps enters the atmosphere.  Shallow seas present very little barrier to methane entering the atmosphere.

[Sigmetnow]

Gerontocrat, SteveMDFP,

Thanks for your comments.  I wasn’t trying to say the problem doesn’t exist (although admittedly the article leans that way).  Just that, as you say, there are many variables and interactions we don’t yet fully understand, and it’s nice to see there are some locations where the planet is still not trying to kill us quite yet.

[Hefaistos]

Here is the paper by Lijing CHENG and Jiang ZHU about ocean temperatures that has been quoted to, and referred to above.

[gerontocrat]

Here is the paper by Lijing CHENG and Jiang ZHU about ocean temperatures that has been quoted to, and referred to above.

Thanks, Hefaistos.

A Chinese Science Institute with access by the public!

My arithmetic tells me that if the average annual increase in Global Ocean Heat Content was applied to the atmosphere it would warm the atmosphere by 1.5+ degrees celsius every year (less radiated imto space). At the moment the oceans are protecting us - but in the longer-term it may bite us in the back of the neck.

[Shared Humanity]

Here is the paper by Lijing CHENG and Jiang ZHU about ocean temperatures that has been quoted to, and referred to above.

Thanks, Hefaistos.

A Chinese Science Institute with access by the public!

My arithmetic tells me that if the average annual increase in Global Ocean Heat Content was applied to the atmosphere it would warm the atmosphere by 1.5+ degrees celsius every year (less radiated imto space). At the moment the oceans are protecting us - but in the longer-term it may bite us in the back of the neck.

The mass of the ocean should allow it to continue to absorb energy from the atmosphere indefinitely, I would think. Acting like an enormous battery, that stored heat will keep the earth warm no matter what we do with CO2.

[Bernard]

Earth is just reinventing the hot water bottle, to keep her feet warm on future cold nights.
https://en.wikipedia.org/wiki/Hot_water_bottle

[Hefaistos]

The mass of the ocean should allow it to continue to absorb energy from the atmosphere indefinitely, I would think. Acting like an enormous battery, that stored heat will keep the earth warm no matter what we do with CO2.

CO2 and ocean heat are highly correlated, see graph.

From another article by same authors:
"This heat storage amounts to an increase of 30.4 × 1022 Joules (J) since 1960 [Cheng et al., 2017], equal to a heating rate of 0.33 Watts per square meter (W m−2) averaged over Earth’s entire surface—0.61 W m−2 after 1992. Improved measurements have revised these values upward by 13% compared with the results of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change....

But what about heat capacity over the full ocean depth? The answer requires a bit more calculation. Any increase in heat contributes to the thermal expansion of seawater and, consequently, SLR [Church et al., 2013]. Any energy added in Earth’s system also causes land-based ice to melt, further contributing to SLR by adding water to the ocean.

Studies show that taking the full ocean depth, ice melt, and other factors into account, Earth is estimated to have gained 0.40 ± 0.09 W m−2 since 1960 and 0.72 W m−2 since 1992 [Cheng et al., 2017]—18% higher than for the top 2,000-meter OHC alone."

https://eos.org/opinions/taking-the-pulse-of-the-planet

[harpy]

Most people who talk about the collapse of coral reefs don't understand that 50% of the coral reefs are now dead.  There's a lag period before the fish in the oceans start to die off relative to that amount.  I don't know what that lag time is, but it's going to be a sudden drop within a year or two. 

After that point hundreds of millions of humans will starve to death from the lack of food from the oceans.  Perhaps it will be a slow process, they wont have any protein so the humans will turn to carbohydrates for the mean time - but at some point the apes will not be able to sustain their civilization due to the lack of protein in their diets and will undergo massive die offs.

I would suspect this will happen within the next couple of years.

Large pelagic fish have life spans of many many years, but as they die off and the coral reefs no longer exist to replenish their population, the humans that require these fish to survive will all die off as well.

We're already past the pelagic fish tipping point, it's now just a waiting game for the effects of dead coral reefs to work their way up the ecosystems around the world.  Expect massive famines and death tolls across the entire globe within the next couple of years.  Civilization will likely be on the brink of collapse as a result of the collapse of coral reef ecosystems. 

It's just a waiting game at this point, and it's a matter of years, not decades.

[Bruce Steele]

Yes the coral reefs worldwide are under very severe stresses due to bleaching events and acidification. The loss of these habitats will negatively affect reef fish populations but I think you might need to link some sources before you can claim Pelagic fish will collapse as a result. Maybe that isn't your intention.
" Eastern Boundrary currents comprise .1% of the worlds oceans but contribute 20% of fish catches."
http://scor-int.org/Annual%20Meetings/2017EC/EBUS.pdf
The eastern boundary currents are not under any immediate threats .
Arctic fisheries are still relatively healthy also.
 Making radical claims about imminent threats of human starvation needs some sort of documentation .
Please source your claims !
It is more than a common courtesy on a science based blog like ASIF , it is how we communicate.
 

[Wherestheice]

Most people who talk about the collapse of coral reefs don't understand that 50% of the coral reefs are now dead.  There's a lag period before the fish in the oceans start to die off relative to that amount.  I don't know what that lag time is, but it's going to be a sudden drop within a year or two. 

After that point hundreds of millions of humans will starve to death from the lack of food from the oceans.  Perhaps it will be a slow process, they wont have any protein so the humans will turn to carbohydrates for the mean time - but at some point the apes will not be able to sustain their civilization due to the lack of protein in their diets and will undergo massive die offs.

I would suspect this will happen within the next couple of years.

Large pelagic fish have life spans of many many years, but as they die off and the coral reefs no longer exist to replenish their population, the humans that require these fish to survive will all die off as well.

We're already past the pelagic fish tipping point, it's now just a waiting game for the effects of dead coral reefs to work their way up the ecosystems around the world.  Expect massive famines and death tolls across the entire globe within the next couple of years.  Civilization will likely be on the brink of collapse as a result of the collapse of coral reef ecosystems. 

It's just a waiting game at this point, and it's a matter of years, not decades.

I agree with this post in many ways, I think collapse of a lot of things will be unfolding soon, but Bruce is right by saying you should provide some links or cited sources

[Avalonian]

I think the problems with these discussions is that we know from studying mass extinctions that collapses happen... but we don't know the exact thresholds at which they occur. At some point ecosystems are undermined past a point at which they can suddenly no longer function, but this point is hard to predict in real time.

Yes, coral is in severe trouble (as it is in every mass extinction event: in times of trouble, don't be a coral reef, marine plankton, or a land vertebrate over 25 kg). However, bleaching can be temporary if temperatures return to acceptable limits within a few months. As the temperatures rise, this rescue effect becomes less likely, of course, but it does mean that there may be a few more years delay before we lose the key reef recources from a purtely practical human perspective. For example, I don't know for sure but I would imagine that the Phillipines' reefs would be far more important for human food supply than the (severely threatened) Great Barrier is, where I believe it's mostly protected from fishing anyway. None of it's good news, but human famine as a result may be a little further away than Harpy suggests.

I have no doubt that we will see ecosystem collapses happening in real time, and soon. But I find it very hard to point to an exact date, since I've seen how ancient communities responded to environmental perturbations in the geological past... and usually, they're surprisingly robust, until suddenly they aren't. My feeling is that agricultural crises will happen before global fisheries crises, since it is much harder to switch to new crops when the weather patterns change abruptly...

After all, we can't grow jellyfish in fields, and they don't seem to struggle with high temperatures. Meet the staple fisheries resource of the future.

https://insideclimatenews.org/species/invertebrates/jellyfish
https://www.sciencedirect.com/science/article/pii/S1385110117300059

[Daniel B.]

Claims of civilization collapse and mass starvation are nothing new.  Paul Ehrlich made a similar claim with his book, Population Bomb, back in 1970.  Others have been regurgitating it since.  The issue is that every time a crisis seems imminent, people take action to stem it.  Those of us who lived through the pollution crisis back then can attest to it.

[Archimid]

Also, civilization collapse and starvation are nothing new, but being alive for a few decades in a first world country will lead to the mistaken belief that it can't happen. Climate change is just now getting started.

[Avalonian]

Indeed, Archimid; uniformitarianism taken to extremes just doesn't work. Civilisations do collapse, and so do global ecosystems, particularly when you get natural perturbations on the scale of the ones that we're making.

Comparing the '70s and '80s (I assume) pollution problems with climate change isn't really useful. Some problems can be easily solved by a concerted effort, and without harmful side-effects. Toxic sludge going into some of your rivers? Legislate to stop it, and those ecosystems soon recover. Ozone hole? Once you stop the CFC (etc.) emissions, the problem starts to resolve; it might takle a while, but it'll get there.

Climate change is a whole other ball game, because of its global scale, cumulative effects with long lag times, major built-in feedbacks, direct impacts on food propduction and water supplies, and the dependence of our economy of things being as they are until the alternatives catch up. Optimism can be useful, but not when it blinds us to how serious the problems really are, and lulls people into thinking that the problems will magically disappear when someone comes up a neat solution. There are, currently, no neat solutions that will work in time. Without the appearance of new technologies such as carbon scrubbing that can be rolled out globally, almost overnight, I don't see that a viable artificial fix is available.

[prairiebotanist]

Indeed, Archimid; uniformitarianism taken to extremes just doesn't work. Civilisations do collapse, and so do global ecosystems, particularly when you get natural perturbations on the scale of the ones that we're making.

Comparing the '70s and '80s (I assume) pollution problems with climate change isn't really useful. Some problems can be easily solved by a concerted effort, and without harmful side-effects. Toxic sludge going into some of your rivers? Legislate to stop it, and those ecosystems soon recover. Ozone hole? Once you stop the CFC (etc.) emissions, the problem starts to resolve; it might takle a while, but it'll get there.

Climate change is a whole other ball game, because of its global scale, cumulative effects with long lag times, major built-in feedbacks, direct impacts on food propduction and water supplies, and the dependence of our economy of things being as they are until the alternatives catch up. Optimism can be useful, but not when it blinds us to how serious the problems really are, and lulls people into thinking that the problems will magically disappear when someone comes up a neat solution. There are, currently, no neat solutions that will work in time. Without the appearance of new technologies such as carbon scrubbing that can be rolled out globally, almost overnight, I don't see that a viable artificial fix is available.

Could this thread be any more off topic?