5 ms·

Low-latitude oceans have become greener in the past 20 years: study

50 points by myshpa 3y ago

thechao 3y ago
Hah! What if Homer's "wine-dark seas" really were wine-dark!?
- layer8 3y ago
  Maybe it’s more indicative of the wine color at the time than the sea color. ;)
  - twoodfin 3y ago
    My guess is that it’s about drawing contrast with the crystal-blue seas near the Greek shore. The difference between the Mediterranean as experienced along the shoals of a beach vs. out among the waves is night and day. Not unlike the difference between a glass of water and a glass of (surely murky in the era) wine.
  - bitwize 3y ago
    Hackernews told me it's because the Greeks couldn't see the color blue -- and neither could anyone else until we invented a word for it.
    - sidlls 3y ago
      That’s physically impossible. The color receptors in our eyes are unlikely to have spontaneously gained the ability to process blue wavelength light only after a word was invented for it. More likely is that people simply didn’t use a separate word to distinguish colors of wavelengths between green and violet.
      - Tenoke 3y ago
        While likely still wrong, Sapir-worf doesn't state that you developed the receptors at the same time but rather that things were processed/compressed/remembered differently when/if there was a single word for e.g. blue and purple. It's closer (if we steelman a bit) to how if I think of different shades of purple as just purple I might not notice a difference between 2 objects while someone else would immediately tell that one is lavender and the other wisteria.
        thechao 3y ago
        Your latter example (but with green) is a testable hypothesis, with some weak support for being true! The rest of S-W is popsci garbage.
      - adrian_b 3y ago
        There are many languages where there is a single word for green and blue, but Greek was not one of those languages. Since the earliest texts, Greek had distinct words for blue and green, even if many modern authors have confused them, because they did not compare enough texts to be able to understand the correspondences between words and colors. Ancient Greek was not uniform, there were many dialects, so there are many authors who use different words for colors. Blue was frequently described as the color of the pigment ultramarine blue or more rarely as the color of the sky. For green there were more words, some of whom have uncertain meaning, like "chloros", which is used in many modern terms for green, but which might have meant something else in Greek. The words whose meaning is certain describe green as the color of grass or as the color of emeralds or as the color of leek.
      - ralferoo 3y ago
        Reminds me of this old image (can't find the original link, but it's the same picture) that jokes about the difference between men and women with names for colours: https://cdn.psychologytoday.com/sites/default/files/styles/article-inline-half-caption/public/field_blog_entry_images/color_differences.jpg https://cdn.psychologytoday.com/sites/default/files/styles/a... Oh, and of course the xkcd follow-up: https://blog.xkcd.com/2010/05/03/color-survey-results/ https://blog.xkcd.com/2010/05/03/color-survey-results/
        bitwize 3y ago
        Fuchsia was named after a botanist named Leonhard Fuchs. To remember its spelling I think of Fred Fuchs, aka Fred Fucks from the AVGN videos, and then add -ia.
    - adrian_b 3y ago
      This is a myth generated by people with little knowledge of chemistry and mineralogy, which prevented them to understand the Greek words that they were reading. Already in Homer, the Greek word for blue was frequently used: "cuaneos", which means "the color of cuanos". "Cuanos" is a word borrowed by the Greeks from Anatolia and which initially designated the blue pigment now named "ultramarine blue", which was imported from Afghanistan. Later, the same word was also applied to other cheaper blue pigments used as a substitute for the expensive ultramarine blue, like azurite and the Egyptian blue. English has the word "cyan", which is derived from the Greek word for blue, but which is now erroneously used with the meaning of blue-green. The Greeks and the Romans described blue-green as the color of the beryls, or of turquoise, or of the littoral sea. They never used "cuaneos", i.e. "cyan", for blue-green. Unfortunately there are many dictionaries with erroneous explanations for Greek words referring to chemical substances, minerals, animals or plants, because the philologists who have worked at the dictionaries have not consulted experts in the other sciences.
      - ano-ther 3y ago
        Yes. The flag of Greece also suggests some fondness for blue (as does its architecture). https://en.m.wikipedia.org/wiki/Flag_of_Greece https://en.m.wikipedia.org/wiki/Flag_of_Greece
      - diogenes4 3y ago
        This would have been an excellent argument had the word been evidenced in use contemporaneously with the Iliad. We have no such evidence of this.
        daveguy 3y ago
        The translation of the Iliad used in the Gutenberg Project[0] refers to deep blue seas twice. [0] https://www.gutenberg.org/files/2199/2199-h/2199-h.htm https://www.gutenberg.org/files/2199/2199-h/2199-h.htm
        diogenes4 3y ago
        You seem to have linked a translation—that is not useful here. Start here instead: https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.01.0133 https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1...
    - tremon 3y ago
      I prefer this reading: https://www.laphamsquarterly.org/sea/winelike-sea https://www.laphamsquarterly.org/sea/winelike-sea > Rather than being ignorant of color, it seems that the Greeks were less interested in and attentive to hue, or tint, than they were to light. As late as the fourth century BC, Plato named the four primary colors as white, black, red, and bright, and in those cases where a Greek writer lists colors “in order,” they are arranged not by the Newtonian colors of the rainbow [..] but from lightest to darkest. > The phrase “winelike,” then, had little to do with color but must have evoked some attribute of dark wine that would resonate with an audience familiar with the sea [..] such as the glint of surface light on impenetrable darkness, like wine in a terracotta vessel. (located at about 70% of the text. Ctrl-F "Plato" for the impatient)
layer8 3y ago
It would be nice to see some before-after pictures.
wilg 3y ago
Is lightening the albedo of the sea helping reflect light and reducing global warming? I know this is a thing with, for example, forests which absorb more heat versus desert.
- daveguy 3y ago
  Greening would be a darkening of the albedo, compared to the light blue of Caribbean waters, helping to absorb light and increase global warming... wouldn't it?
  - pshirshov 3y ago
    Should be no significant difference: https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Solar_spectrum_en.svg/280px-Solar_spectrum_en.svg.png https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/So...
    - daveguy 3y ago
      Excellent response! But I'd like to point out that the curve around the lower wavelengths in the absorbance spectrum is less than 1 W/m^2/nm whereas in the middle of the spectrum it is closer to 1.3 W/m^2/nm (according to your source) ... I would say a 30% increase is significant. To be clear I wasn't saying anything about the net impact to global warming. I'm sure the CO2 capture by increased algae is also significant (maybe/likely more). I was only referring to the electromagnetic absorbance variable.
  - nomel 3y ago
    It’s a system, so you can’t just look at one parameter in isolation. 50% of our oxygen comes from the ocean, which also means it’s the single largest carbon sink on the planet [1]. Darker, but also an improvement to one of the primary drivers for why CO2 is near the lowest it’s ever been [2]. [1] https://www.weforum.org/agenda/2020/10/oceans-absorb-carbon-seas-climate-change-environment-water-co2/ https://www.weforum.org/agenda/2020/10/oceans-absorb-carbon-... [2] http://earthguide.ucsd.edu/virtualmuseum/images/CO2History.html http://earthguide.ucsd.edu/virtualmuseum/images/CO2History.h...
petermcneeley 3y ago
>Generally, waters that are deep blue reflect very little life, whereas greener waters indicate the presence of ecosystems, and mainly phytoplankton—plant-like microbes that are abundant in upper ocean and that contain the green pigment chlorophyll. The pigment helps plankton harvest sunlight, which they use to capture carbon dioxide from the atmosphere and convert it into sugars. This is a negative feedback on global warming?
- wseqyrku 3y ago
  How did you come up with that connection?
  - petermcneeley 3y ago
    I was quoting from the reference article https://phys.org/news/2023-07-ocean-consequence-climate.html https://phys.org/news/2023-07-ocean-consequence-climate.html
- emmelaich 3y ago
  Negative as in reducing global warming, yes. Phytoplankton are an enormous carbon sink. I don't know why we'd "fear" a greener ocean. It's probably a return to the colour of 200 years ago.
  - myshpa 3y ago
    The seas are not greener because we have more phytoplankton. Also, there are many species of phytoplankton, some even harmful, so it may mean changes in their biodiversity. https://www.scientificamerican.com/article/phytoplankton-population/ https://www.scientificamerican.com/article/phytoplankton-pop... Phytoplankton Population Drops 40 Percent Since 1950 https://www.pnas.org/doi/10.1073/pnas.2019591118 https://www.pnas.org/doi/10.1073/pnas.2019591118 Phytoplankton biodiversity is more important for ecosystem functioning in highly variable thermal environments https://www.nature.com/articles/s41467-021-25699-w https://www.nature.com/articles/s41467-021-25699-w We find that the rate of turnover in the phytoplankton community becomes faster during this century, that is, the community structure becomes increasingly unstable in response to climate change. Combined with alterations to phytoplankton diversity, our results imply a loss of ecological resilience with likely knock-on effects on the productivity and functioning of the marine environment.
formvoltron 3y ago
article says "we predicted it" but.. "we don't know what is causing it... " eh?
- HocusLocus 3y ago
  The paper ( https://www.nature.com/articles/s41586-023-06321-z.pdf https://www.nature.com/articles/s41586-023-06321-z.pdf ) seems to be written in "whistling in the dark" mode where coastal pollution and algae blooms, which covered ~8.6% of the ocean surface in 2020 ( https://www.worldatlas.com/oceans/study-reveals-why-coastal-algae-blooms-now-cover-over-8-6-of-total-ocean-surface-area.html https://www.worldatlas.com/oceans/study-reveals-why-coastal-... )... are studiously unmentioned. They have to tie it all instead somehow to 'warming' and more distantly to CO2 in atmosphere and be professionally 'mystified' by any other causes, to unlock the funding achievement to use the term Climate Change in their paper and make it citeable. If they don't know what may be causing it, they might browse the lines of their own computer model that predicted it and see what they say.

50 points by myshpa 3y ago

thechao 3y ago

Hah! What if Homer's "wine-dark seas" really were wine-dark!?

layer8 3y ago
Maybe it’s more indicative of the wine color at the time than the sea color. ;)
- twoodfin 3y ago
  My guess is that it’s about drawing contrast with the crystal-blue seas near the Greek shore. The difference between the Mediterranean as experienced along the shoals of a beach vs. out among the waves is night and day. Not unlike the difference between a glass of water and a glass of (surely murky in the era) wine.
- bitwize 3y ago
  Hackernews told me it's because the Greeks couldn't see the color blue -- and neither could anyone else until we invented a word for it.
  - sidlls 3y ago
    That’s physically impossible. The color receptors in our eyes are unlikely to have spontaneously gained the ability to process blue wavelength light only after a word was invented for it. More likely is that people simply didn’t use a separate word to distinguish colors of wavelengths between green and violet.
    - Tenoke 3y ago
      While likely still wrong, Sapir-worf doesn't state that you developed the receptors at the same time but rather that things were processed/compressed/remembered differently when/if there was a single word for e.g. blue and purple. It's closer (if we steelman a bit) to how if I think of different shades of purple as just purple I might not notice a difference between 2 objects while someone else would immediately tell that one is lavender and the other wisteria.
      - thechao 3y ago
        Your latter example (but with green) is a testable hypothesis, with some weak support for being true! The rest of S-W is popsci garbage.
    - adrian_b 3y ago
      There are many languages where there is a single word for green and blue, but Greek was not one of those languages. Since the earliest texts, Greek had distinct words for blue and green, even if many modern authors have confused them, because they did not compare enough texts to be able to understand the correspondences between words and colors. Ancient Greek was not uniform, there were many dialects, so there are many authors who use different words for colors. Blue was frequently described as the color of the pigment ultramarine blue or more rarely as the color of the sky. For green there were more words, some of whom have uncertain meaning, like "chloros", which is used in many modern terms for green, but which might have meant something else in Greek. The words whose meaning is certain describe green as the color of grass or as the color of emeralds or as the color of leek.
    - ralferoo 3y ago
      Reminds me of this old image (can't find the original link, but it's the same picture) that jokes about the difference between men and women with names for colours: https://cdn.psychologytoday.com/sites/default/files/styles/article-inline-half-caption/public/field_blog_entry_images/color_differences.jpg https://cdn.psychologytoday.com/sites/default/files/styles/a... Oh, and of course the xkcd follow-up: https://blog.xkcd.com/2010/05/03/color-survey-results/ https://blog.xkcd.com/2010/05/03/color-survey-results/
      - bitwize 3y ago
        Fuchsia was named after a botanist named Leonhard Fuchs. To remember its spelling I think of Fred Fuchs, aka Fred Fucks from the AVGN videos, and then add -ia.
  - adrian_b 3y ago
    This is a myth generated by people with little knowledge of chemistry and mineralogy, which prevented them to understand the Greek words that they were reading. Already in Homer, the Greek word for blue was frequently used: "cuaneos", which means "the color of cuanos". "Cuanos" is a word borrowed by the Greeks from Anatolia and which initially designated the blue pigment now named "ultramarine blue", which was imported from Afghanistan. Later, the same word was also applied to other cheaper blue pigments used as a substitute for the expensive ultramarine blue, like azurite and the Egyptian blue. English has the word "cyan", which is derived from the Greek word for blue, but which is now erroneously used with the meaning of blue-green. The Greeks and the Romans described blue-green as the color of the beryls, or of turquoise, or of the littoral sea. They never used "cuaneos", i.e. "cyan", for blue-green. Unfortunately there are many dictionaries with erroneous explanations for Greek words referring to chemical substances, minerals, animals or plants, because the philologists who have worked at the dictionaries have not consulted experts in the other sciences.
    - ano-ther 3y ago
      Yes. The flag of Greece also suggests some fondness for blue (as does its architecture). https://en.m.wikipedia.org/wiki/Flag_of_Greece https://en.m.wikipedia.org/wiki/Flag_of_Greece
    - diogenes4 3y ago
      This would have been an excellent argument had the word been evidenced in use contemporaneously with the Iliad. We have no such evidence of this.
      - daveguy 3y ago
        The translation of the Iliad used in the Gutenberg Project[0] refers to deep blue seas twice. [0] https://www.gutenberg.org/files/2199/2199-h/2199-h.htm https://www.gutenberg.org/files/2199/2199-h/2199-h.htm
        diogenes4 3y ago
        You seem to have linked a translation—that is not useful here. Start here instead: https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.01.0133 https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1...
  - tremon 3y ago
    I prefer this reading: https://www.laphamsquarterly.org/sea/winelike-sea https://www.laphamsquarterly.org/sea/winelike-sea > Rather than being ignorant of color, it seems that the Greeks were less interested in and attentive to hue, or tint, than they were to light. As late as the fourth century BC, Plato named the four primary colors as white, black, red, and bright, and in those cases where a Greek writer lists colors “in order,” they are arranged not by the Newtonian colors of the rainbow [..] but from lightest to darkest. > The phrase “winelike,” then, had little to do with color but must have evoked some attribute of dark wine that would resonate with an audience familiar with the sea [..] such as the glint of surface light on impenetrable darkness, like wine in a terracotta vessel. (located at about 70% of the text. Ctrl-F "Plato" for the impatient)

layer8 3y ago

It would be nice to see some before-after pictures.

wilg 3y ago

Is lightening the albedo of the sea helping reflect light and reducing global warming? I know this is a thing with, for example, forests which absorb more heat versus desert.

daveguy 3y ago
Greening would be a darkening of the albedo, compared to the light blue of Caribbean waters, helping to absorb light and increase global warming... wouldn't it?
- pshirshov 3y ago
  Should be no significant difference: https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Solar_spectrum_en.svg/280px-Solar_spectrum_en.svg.png https://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/So...
  - daveguy 3y ago
    Excellent response! But I'd like to point out that the curve around the lower wavelengths in the absorbance spectrum is less than 1 W/m^2/nm whereas in the middle of the spectrum it is closer to 1.3 W/m^2/nm (according to your source) ... I would say a 30% increase is significant. To be clear I wasn't saying anything about the net impact to global warming. I'm sure the CO2 capture by increased algae is also significant (maybe/likely more). I was only referring to the electromagnetic absorbance variable.
- nomel 3y ago
  It’s a system, so you can’t just look at one parameter in isolation. 50% of our oxygen comes from the ocean, which also means it’s the single largest carbon sink on the planet [1]. Darker, but also an improvement to one of the primary drivers for why CO2 is near the lowest it’s ever been [2]. [1] https://www.weforum.org/agenda/2020/10/oceans-absorb-carbon-seas-climate-change-environment-water-co2/ https://www.weforum.org/agenda/2020/10/oceans-absorb-carbon-... [2] http://earthguide.ucsd.edu/virtualmuseum/images/CO2History.html http://earthguide.ucsd.edu/virtualmuseum/images/CO2History.h...

petermcneeley 3y ago

>Generally, waters that are deep blue reflect very little life, whereas greener waters indicate the presence of ecosystems, and mainly phytoplankton—plant-like microbes that are abundant in upper ocean and that contain the green pigment chlorophyll. The pigment helps plankton harvest sunlight, which they use to capture carbon dioxide from the atmosphere and convert it into sugars. This is a negative feedback on global warming?

wseqyrku 3y ago
How did you come up with that connection?
- petermcneeley 3y ago
  I was quoting from the reference article https://phys.org/news/2023-07-ocean-consequence-climate.html https://phys.org/news/2023-07-ocean-consequence-climate.html
emmelaich 3y ago
Negative as in reducing global warming, yes. Phytoplankton are an enormous carbon sink. I don't know why we'd "fear" a greener ocean. It's probably a return to the colour of 200 years ago.
- myshpa 3y ago
  The seas are not greener because we have more phytoplankton. Also, there are many species of phytoplankton, some even harmful, so it may mean changes in their biodiversity. https://www.scientificamerican.com/article/phytoplankton-population/ https://www.scientificamerican.com/article/phytoplankton-pop... Phytoplankton Population Drops 40 Percent Since 1950 https://www.pnas.org/doi/10.1073/pnas.2019591118 https://www.pnas.org/doi/10.1073/pnas.2019591118 Phytoplankton biodiversity is more important for ecosystem functioning in highly variable thermal environments https://www.nature.com/articles/s41467-021-25699-w https://www.nature.com/articles/s41467-021-25699-w We find that the rate of turnover in the phytoplankton community becomes faster during this century, that is, the community structure becomes increasingly unstable in response to climate change. Combined with alterations to phytoplankton diversity, our results imply a loss of ecological resilience with likely knock-on effects on the productivity and functioning of the marine environment.

formvoltron 3y ago

article says "we predicted it" but.. "we don't know what is causing it... " eh?

HocusLocus 3y ago
The paper ( https://www.nature.com/articles/s41586-023-06321-z.pdf https://www.nature.com/articles/s41586-023-06321-z.pdf ) seems to be written in "whistling in the dark" mode where coastal pollution and algae blooms, which covered ~8.6% of the ocean surface in 2020 ( https://www.worldatlas.com/oceans/study-reveals-why-coastal-algae-blooms-now-cover-over-8-6-of-total-ocean-surface-area.html https://www.worldatlas.com/oceans/study-reveals-why-coastal-... )... are studiously unmentioned. They have to tie it all instead somehow to 'warming' and more distantly to CO2 in atmosphere and be professionally 'mystified' by any other causes, to unlock the funding achievement to use the term Climate Change in their paper and make it citeable. If they don't know what may be causing it, they might browse the lines of their own computer model that predicted it and see what they say.