5 ms·

Today's North Atlantic Sea Surface Temperature (4.8 Sigma)

66 points by myshpa 3y ago

myshpa 3y ago
4 sigma is once every 43 years (twice in a lifetime) 4.5 sigma is once every 403 years (once in the modern era) 5 sigma is once every 4776 years (once in recorded history)
- ttymck 3y ago
  How do you derive these? Edit: probability for daily event, see here: https://en.m.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule https://en.m.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_r...
- myshpa 3y ago
  https://www.abc.net.au/news/2023-07-24/antarctic-sea-ice-levels-nosedive-five-sigma-event/102635204 https://www.abc.net.au/news/2023-07-24/antarctic-sea-ice-lev... "The consensus statement at the moment would be that this is largely anthropogenic forces that have caused the ocean to warm, for the atmosphere to be highly disturbed and to affect the sea ice," Dr Heil said. ... Either way, she fears a further change in the balance could trigger a tipping point from where it's difficult to reverse the trajectory. ... "I think a lot of people have the time line too long out, saying this won't affect them. I'm pretty convinced that this is something my generation will experience."
  - atkailash 3y ago
    [dead]
roflyear 3y ago
Totally insane. The water by me is 82'. The highest it has ever been before this year was 78ish.
llamaLord 3y ago
Is the frog boiling yet? Can we start doing something about all this now please?
- pstuart 3y ago
  [flagged]
  - llamaLord 3y ago
    Honestly this is the thing that scares me the most, for non-trivia portion of the population the apocalypse isn't necessarily something to avoid, its almost equivalent to their "endgame".
    - pstuart 3y ago
      Yeah, me too. And that same craziness extends all the way up the stack to so much more day to day pain and suffering.
- fbrncci 3y ago
  Do what, exactly?
  - gary_0 3y ago
    It's December 7, 1941. The Japanese have just attacked Pearl Harbor. Suddenly, most people realize the status quo has changed. The economy needs to make a major transition. Things need to be built at an unprecedented rate. Sacrifices will need to be made at every level because survival is on the line. Victory is possible but it will be a long and difficult fight. Do we throw up our collective hands and say "it's too hard, the job is too big, not enough people are willing, we surrender"? Or do we shut up and get to work? The transition away from a carbon-emitting economy can be done if we have the will, and we will come out of it stronger than ever. We just need to stop saying we can't, and start building.
    - 3y ago
freedryk 3y ago
What's really astonishing about this is that to increase sea surface temperature by 1.5 degrees C, you need to heat the whole ocean mixed layer, which in summer is around 50 meters deep. E = c_p * rho * h * dT ~ (4e3 J / kg K) * (10e3 kg / m^3) * (50 m) * (1.5 K) = 3e8 J / m^2. So over the whole North Atlantic, this is about a (4e14 m^2) * (3e8 J / m^2) = 1.2e23 Joules of energy that have been added to the North Atlantic. That's about the same amount of energy that the whole Earth absorbs from the sun in a month.
JumpCrisscross 3y ago
Do we have sea temperature data from before 1982? Like, thousands of years'?
- bandushrew 3y ago
  https://www.smithsonianmag.com/blogs/national-museum-of-natural-history/2018/03/23/heres-how-scientists-reconstruct-earths-past-climates/#:~:text=The%20true%20heavyweights%20for%20reconstructing,have%20an%20exquisite%20fossil%20record https://www.smithsonianmag.com/blogs/national-museum-of-natu.... "The true heavyweights for reconstructing ancient seawater temperatures are the microorganisms. Foraminifera, single-celled organisms roughly the size of the period ending this sentence, occur nearly everywhere in the oceans and have an exquisite fossil record."
- freedryk 3y ago
  We have reasonably accurate sea surface temperature data from 1945 to present, about 78 years. We have less accurate measurements back to the 1880s. Finally, we have proxy records going back thousands of years, based on isotope fractionation ratios and other paleoclimate data.
  - sounds 3y ago
    I located https://www.epa.gov/climate-indicators/climate-change-indicators-sea-surface-temperature https://www.epa.gov/climate-indicators/climate-change-indica... Especially Figure 2 on that page, a map showing the change in Sea Surface Temperature, was interesting. Do you have more information on what changed around 1945? (I mean, I could probably guess. I was wondering if you're looking at different sources than I am.)
  - hulitu 3y ago
    On how many points ? The ocean is big, you know.
deleted 3y ago
[deleted]

66 points by myshpa 3y ago

4 sigma is once every 43 years (twice in a lifetime) 4.5 sigma is once every 403 years (once in the modern era) 5 sigma is once every 4776 years (once in recorded history)

ttymck 3y ago
How do you derive these? Edit: probability for daily event, see here: https://en.m.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule https://en.m.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_r...
myshpa 3y ago
https://www.abc.net.au/news/2023-07-24/antarctic-sea-ice-levels-nosedive-five-sigma-event/102635204 https://www.abc.net.au/news/2023-07-24/antarctic-sea-ice-lev... "The consensus statement at the moment would be that this is largely anthropogenic forces that have caused the ocean to warm, for the atmosphere to be highly disturbed and to affect the sea ice," Dr Heil said. ... Either way, she fears a further change in the balance could trigger a tipping point from where it's difficult to reverse the trajectory. ... "I think a lot of people have the time line too long out, saying this won't affect them. I'm pretty convinced that this is something my generation will experience."
- atkailash 3y ago
  [dead]

roflyear 3y ago

Totally insane. The water by me is 82'. The highest it has ever been before this year was 78ish.

llamaLord 3y ago

Is the frog boiling yet? Can we start doing something about all this now please?

pstuart 3y ago
[flagged]
- llamaLord 3y ago
  Honestly this is the thing that scares me the most, for non-trivia portion of the population the apocalypse isn't necessarily something to avoid, its almost equivalent to their "endgame".
  - pstuart 3y ago
    Yeah, me too. And that same craziness extends all the way up the stack to so much more day to day pain and suffering.
fbrncci 3y ago
Do what, exactly?
- gary_0 3y ago
  It's December 7, 1941. The Japanese have just attacked Pearl Harbor. Suddenly, most people realize the status quo has changed. The economy needs to make a major transition. Things need to be built at an unprecedented rate. Sacrifices will need to be made at every level because survival is on the line. Victory is possible but it will be a long and difficult fight. Do we throw up our collective hands and say "it's too hard, the job is too big, not enough people are willing, we surrender"? Or do we shut up and get to work? The transition away from a carbon-emitting economy can be done if we have the will, and we will come out of it stronger than ever. We just need to stop saying we can't, and start building.
  - 3y ago

freedryk 3y ago

What's really astonishing about this is that to increase sea surface temperature by 1.5 degrees C, you need to heat the whole ocean mixed layer, which in summer is around 50 meters deep. E = c_p * rho * h * dT ~ (4e3 J / kg K) * (10e3 kg / m^3) * (50 m) * (1.5 K) = 3e8 J / m^2. So over the whole North Atlantic, this is about a (4e14 m^2) * (3e8 J / m^2) = 1.2e23 Joules of energy that have been added to the North Atlantic. That's about the same amount of energy that the whole Earth absorbs from the sun in a month.

JumpCrisscross 3y ago

Do we have sea temperature data from before 1982? Like, thousands of years'?

bandushrew 3y ago
https://www.smithsonianmag.com/blogs/national-museum-of-natural-history/2018/03/23/heres-how-scientists-reconstruct-earths-past-climates/#:~:text=The%20true%20heavyweights%20for%20reconstructing,have%20an%20exquisite%20fossil%20record https://www.smithsonianmag.com/blogs/national-museum-of-natu.... "The true heavyweights for reconstructing ancient seawater temperatures are the microorganisms. Foraminifera, single-celled organisms roughly the size of the period ending this sentence, occur nearly everywhere in the oceans and have an exquisite fossil record."
freedryk 3y ago
We have reasonably accurate sea surface temperature data from 1945 to present, about 78 years. We have less accurate measurements back to the 1880s. Finally, we have proxy records going back thousands of years, based on isotope fractionation ratios and other paleoclimate data.
- sounds 3y ago
  I located https://www.epa.gov/climate-indicators/climate-change-indicators-sea-surface-temperature https://www.epa.gov/climate-indicators/climate-change-indica... Especially Figure 2 on that page, a map showing the change in Sea Surface Temperature, was interesting. Do you have more information on what changed around 1945? (I mean, I could probably guess. I was wondering if you're looking at different sources than I am.)
- hulitu 3y ago
  On how many points ? The ocean is big, you know.

deleted 3y ago

[deleted]