Ocean oxygen levels are on the decline

[CubsFan]

Sprinkler heads everywhere? Otherwise nothing would grow?
I’m confused. Are you in someone’s back yard?

 

[Scrubber_steve]

"How did life in the ocean survive, & how were calcifying organisms able to produce major reef building episodes
when CO2 was on average 5,000 ppm (12.5 times present levels) & global temperatures was on average 8C warmer than now???"

Let me try. because the reef evolved in those temps over a long time period. The ocean warning we see today is unprecedented in history and the corals can not adapt fast enough?

It is not unprecedented at all. The ocean was warmer by about 0.7C during the Holocene maximum.

 

[Scrubber_steve]

the energy needed to warm the atmosphere by 100C would only warm the ocean by 1C, because of the heat capacity of the ocean is so much larger.

Error. That should have read -
'the energy needed to warm the
atmosphere by 1000C would only warm the ocean by 1C, because of the heat capacity of the ocean is so much larger.

 

[Scrubber_steve]

"How did life in the ocean survive, & how were calcifying organisms able to produce major reef building episodes
when CO2 was on average 5,000 ppm (12.5 times present levels) & global temperatures was on average 8C warmer than now???"

Let me try. because the reef evolved in those temps over a long time period. The ocean warning we see today is unprecedented in history and the corals can not adapt fast enough?

The main point I am making is, CO2 was 5,000ppm, yet calcifying organisms were able to produce major reef building episodes - the pH of the oceans wasn't affected - ocean acidification did not occur - ocean surface pH is not controlled by atmospheric CO2 levels, its controlled by upwelling from the deep ocean.

 

[Scrubber_steve]

I stopped reading magazines like this because there is no science in them anymore.

there's plenty of pseudo-science in them.

 

[CubsFan]

The main point I am making is, CO2 was 5,000ppm, yet calcifying organisms were able to produce major reef building episodes - the pH of the oceans wasn't affected - ocean acidification did not occur - ocean surface pH is not controlled by atmospheric CO2 levels, its controlled by upwelling from the deep ocean.

https://www.climate.gov/news-featur...ate/climate-change-atmospheric-carbon-dioxide
I think this article disputes your assertion that atmospheric co2 has no effect on ocean acidification. I might be mistaken. It’s worth a read.

 

[WVNed]

I am sure the property belonged to someone. The sprinkler heads where in a grid pattern up in the hills behind commercial property.
I was in Temecula Ca

 

[Steve_Skullsplitter0]

there's plenty of pseudo-science in them.

I get my science education from Rick N Morty. Theres more facts involved.


Seriously though by the time the ocean O2 levels drop enough to make noticable impact we will have been wiped out by Yellowstone super volcano, some random meteor, nukes, AI, ET, zombies or Godzilla.

 

[Ardeus]

Phytoplankton declines being observed all over the globe may contribute to this. In places like the arctic (where temperature is increasing 3 to 4 times faster than the rest of the globe), it has collapsed by almost 90% since the 1950's.

On the other hand the increase in CO2 levels is not only caused by increased emissions. Carbon sinks (like phytoplankton and forests) are failing and unable to remove as much CO2 as they would normally.



Increased temperature of the ocean also plays a part in the O2 content of water.

 

[Scrubber_steve]

https://www.climate.gov/news-featur...ate/climate-change-atmospheric-carbon-dioxide
I think this article disputes your assertion that atmospheric co2 has no effect on ocean acidification. I might be mistaken. It’s worth a read.

OK then, explain how organisms were able to calcify when ocean surface pH was 5,000 ppm?

here's one example of natural pH fluctuation where atmospheric CO2 would have had no effect, certainly prior to the 1950s onwards

Decadal variability in seawater pH in the West Pacific: Evidence from coral δ 11 B records
Wei et al 2015


Abstract
Long-term seawater pH records are essential for evaluating the rates of ocean acidification (OA) driven by anthropogenic emissions. Widespread, natural decadal variability in seawater pH superimposes on the long-term anthropogenic variations, likely influencing the OA rates estimated from the pH records. Here, we report a record of annual seawater pH estimated using the δ11B proxy over the past 159 years reconstructed from a Porites coral collected to the east of Hainan Island in the northern South China Sea (SCS). By coupling this time series with previously reported long-term seawater pH records in the West Pacific, the decadal variability in seawater pH records and its possible driving mechanisms were investigated. The results indicate that large decadal variability in seawater pH has occurred off eastern Hainan Island over the past 159 years, in agreement with previous records. The Qiongdong upwelling system, which controls nutrient supplies, regulates surface water productivity, and is driven by the East Asian summer monsoon, is the primary control of this decadal variability, while terrestrial inputs appear not influence significantly. Meanwhile the impacts of the Pacific Decadal Oscillation (PDO) and the El Nino and Southern Oscillation (ENSO) systems on seawater pH off eastern Hainan Island is likely limited. In contrast, the PDO is the main factor to influence the decadal seawater pH variability offshore the East Australia, while the mechanism controlling the decadal seawater pH variability in Guam is not clear yet. Meanwhile, The rate of decrease in seawater pH estimated from coral records are significantly different in different regions and over different time spans, which may reflect a combination of natural decadal variability in seawater pH and long-term variations. Therefore, understanding the mechanisms driving natural variability in seawater pH is important for improving estimates of ocean acidification rates driven by anthropogenic emissions. end.
https://www.researchgate.net/public...st_Pacific_Evidence_from_coral_d_11_B_records

The carbon atom from atmospheric co2 entering the oceans surface is used to build tissue mass, firstly through photosynthesis, predominantly by phytoplankton. It is eaten by other organisms, & so on, recycled over and over again. This is why aquariums with effective algae filtration don't have pH issues.
After hydration, co2 becomes bicarbonate & carbonate. Other organisms, such as macro algae & coral, convert the bicarbonate back into co2 for photosynthesis. Calcifying organisms take up the carbonates, along with calcium to build structures locking up the carbon. This regulates ocean surface pH. The more co2, the greater the photosynthesis.

Below a certain depth, referred to as the pH horizon (from memory) the pH is far lower because these organisms all die, & release the carbon back into the water. It is this lower pH water that upwells to the surface changing the pH level over time, while atmospheric co2 levels remain static.

 

[Scrubber_steve]

Phytoplankton declines being observed all over the globe may contribute to this. In places like the arctic (where temperature is increasing 3 to 4 times faster than the rest of the globe), it has collapsed by almost 90% since the 1950's.

NASA don't contribute the decline in phyto to temperature, but to a lack of nutrients, which would be a natural variation -
"The phytoplankton can run out of nutrients," said Rousseaux, which is what they observed in the nutrient levels essential to diatoms reported by the model. Why the mixed layer shallowed is still uncertain. One possibility is changes in winds, which cause some of the churning", she said.
And further -
"The diatom decline, while statistically significant, is not severe"

On the other hand the increase in CO2 levels is not only caused by increased emissions. Carbon sinks (like phytoplankton and forests) are failing and unable to remove as much CO2 as they would normally.

There is no data at all to support your assertion that the Earths natural carbon sinks are becoming less efficient.

 

[Fourstars]

It is not unprecedented at all. The ocean was warmer by about 0.7C during the Holocene maximum.

I'm in way over my head. but didn't the holocene optimum occur over a few thousand years and not over a century like current temperature rise?

 

[CubsFan]

OK then, explain how organisms were able to calcify when ocean surface pH was 5,000 ppm?

here's one example of natural pH fluctuation where atmospheric CO2 would have had no effect, certainly prior to the 1950s onwards

Decadal variability in seawater pH in the West Pacific: Evidence from coral δ 11 B records
Wei et al 2015


Abstract
Long-term seawater pH records are essential for evaluating the rates of ocean acidification (OA) driven by anthropogenic emissions. Widespread, natural decadal variability in seawater pH superimposes on the long-term anthropogenic variations, likely influencing the OA rates estimated from the pH records. Here, we report a record of annual seawater pH estimated using the δ11B proxy over the past 159 years reconstructed from a Porites coral collected to the east of Hainan Island in the northern South China Sea (SCS). By coupling this time series with previously reported long-term seawater pH records in the West Pacific, the decadal variability in seawater pH records and its possible driving mechanisms were investigated. The results indicate that large decadal variability in seawater pH has occurred off eastern Hainan Island over the past 159 years, in agreement with previous records. The Qiongdong upwelling system, which controls nutrient supplies, regulates surface water productivity, and is driven by the East Asian summer monsoon, is the primary control of this decadal variability, while terrestrial inputs appear not influence significantly. Meanwhile the impacts of the Pacific Decadal Oscillation (PDO) and the El Nino and Southern Oscillation (ENSO) systems on seawater pH off eastern Hainan Island is likely limited. In contrast, the PDO is the main factor to influence the decadal seawater pH variability offshore the East Australia, while the mechanism controlling the decadal seawater pH variability in Guam is not clear yet. Meanwhile, The rate of decrease in seawater pH estimated from coral records are significantly different in different regions and over different time spans, which may reflect a combination of natural decadal variability in seawater pH and long-term variations. Therefore, understanding the mechanisms driving natural variability in seawater pH is important for improving estimates of ocean acidification rates driven by anthropogenic emissions. end.
https://www.researchgate.net/public...st_Pacific_Evidence_from_coral_d_11_B_records

The carbon atom from atmospheric co2 entering the oceans surface is used to build tissue mass, firstly through photosynthesis, predominantly by phytoplankton. It is eaten by other organisms, & so on, recycled over and over again. This is why aquariums with effective algae filtration don't have pH issues.
After hydration, co2 becomes bicarbonate & carbonate. Other organisms, such as macro algae & coral, convert the bicarbonate back into co2 for photosynthesis. Calcifying organisms take up the carbonates, along with calcium to build structures locking up the carbon. This regulates ocean surface pH. The more co2, the greater the photosynthesis.

Below a certain depth, referred to as the pH horizon (from memory) the pH is far lower because these organisms all die, & release the carbon back into the water. It is this lower pH water that upwells to the surface changing the pH level over time, while atmospheric co2 levels remain static.

I cited an article. I've heard differently from what you stated, so I did a google search. You'd have to ask the good people at NOAA your question. I'm not much for these discussions that go no where and I would hate to give anyone the idea that I think I'm an expert on the subject.

Bryce Harper to the Phillies? 13 years? The state of free agency in baseball? Now there's a discussion worth having.

 

[Dr. Dendrostein]

This is grade A global warming alarmism.
Declining O2 levels or not, it is not proof of warming, let alone man made warming.

Did you know that the energy needed to warm the atmosphere by 100C would only warm the ocean by 1C, because of the heat capacity of the ocean is so much larger.

Between 2005 and 2017, the global network of thousands of Argo floats have measured an average temperature increase of the upper half of the ocean of 0.04 deg. C.
That’s less than 0.004 C/year, an inconceivably small number.

How did life in the ocean survive, & how were calcifying organisms able to produce major reef building episodes
when CO2 was on average 5,000 ppm (12.5 times present levels) & global temperatures was on average 8C warmer than now???



https://en.wikipedia.org/wiki/Coral_reef#History

Times of maximum reef development were

A. The Middle Cambrian 513–501 million years ago (CO2 over 5,000 ppm, average temperature 8°C above present

B. The Devonian 416–359 million years ago (CO2 3,000 to 4,000 ppm, average temperature 8°C above present

C. The Carboniferous 359–299 million years ago (CO2 at present level, temperature range 6°C above present to 10°C below present

D. Late Cretaceous 100–66 million years ago (CO2 1,000 ppm, average temperature 8°C above present

E. And all Neogene 23 million years ago to present), owing to order Scleractinia corals. (CO2 above, to well below present levels, temperature range 5°C above present to 10°C below present.


As seen in the graph calcareous reefs in one form or another have evolved & persisted through all the extremes of ocean & atmospheric temperatures ranges, & carbon dioxide level fluctuations imaginable.
CO2 levels from over 5,000 ppm to 150 ppm. Average high temperatures of 10°C above present to 10°C below present. And seal levels that have fluctuated by more than 300 metres, possibly more than 400 metres, over geologic time.

And yet they have persisted. And although reefs that existed during the Middle Cambrian period (513–501 million years ago) resulted from calcareous algae and archaeocyathids, they were still calcifying organisms like corals are today. What was the pH of the ocean at that time when atmospheric CO2 was over 5,000 ppm? 12.5 times higher than today, in water far warmer than now?

Very simple the dodo bird gone because of man, messenger pigeon gone because of man. I can't go to the grocery store and buy fresh abalone, abalone!!! Let alone in 15 ounce can.

 

[Righteous]

I didn’t realize the article would start such a brew haha

I definitely don’t want to get into any political stuff, but there’s a lot of bad or lack of science understanding in this thread.

For instance, yes the Holocene had warming like today, however it was over thousands of years, also not a global event. Also that doesn’t refute any inpact or data about today’s warming.

Anyway, just for the record in case people are looking for some scientifically accepted data:

https://grist.org/series/skeptics/

 

[Scrubber_steve]

OK then, explain how organisms were able to calcify when ocean surface pH was 5,000 ppm?

error. that should have read - explain how organisms were able to calcify when atmospheric co2 was at 5,000 ppm?

 

[Scrubber_steve]

I'm in way over my head. but didn't the holocene optimum occur over a few thousand years and not over a century like current temperature rise?

Yes. But the oceans haven't warmed up by 0.7C either.
And don't be led into the realm of pseudo-science where it is asserted that any ocean warming is proof of anthropogenic influence. :)

 

[wesman42]

Thought this was pretty cool on another note:
https://www.independent.co.uk/news/...ty-melbourne-dorna-esrafilzadeh-a8798031.html

 

[Scrubber_steve]

I didn’t realize the article would start such a brew haha

I definitely don’t want to get into any political stuff, but there’s a lot of bad or lack of science understanding in this thread.

For instance, yes the Holocene had warming like today, however it was over thousands of years, also not a global event. Also that doesn’t refute any inpact or data about today’s warming.

The Holocene was global, & warmer than today. The Roman & Medieval warming were also global & warmer than the present. There are numerous studies that prove this.
This argument, that these periods were just regional changes, & global temps were on average no different, or cooler than today is propaganda pushed because co2 levels at these times were not fluctuating, & only at 280ppm & the alarmists want people to believe that climate cannot change unless co2 is changing.

 

[Fourstars]

Yes. But the oceans haven't warmed up by 0.7C either.
And don't be led into the realm of pseudo-science where it is asserted that any ocean warming is proof of anthropogenic influence. :)

Ok, I will do more reading instead of just taking everything I see on the latest documentary as fact, or the only causation. I watch one (don't remember the title) on the 2016 coral bleaching on the GBR last weekend and have been very depressed all week. First time I was moved to tears in years.