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Earth Stats Science

Past Measurements May Have Missed Massive Ocean Warming 423

An anonymous reader writes "Previous estimates of global ocean warming have been significantly underestimated due to historically sparse temperature data from the Southern Ocean, new research has found. From the article: "Earth's oceans have absorbed more than 90% of the warming caused by greenhouse gases, researchers estimate, with the stored heat showing up as warmer seawater. But a new analysis suggests scientists may have underestimated the size of the heat sink in the upper ocean—which could have implications for researchers trying to understand the pace and scale of past warming."
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Past Measurements May Have Missed Massive Ocean Warming

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  • by wvmarle ( 1070040 ) on Monday October 06, 2014 @05:22AM (#48071701)

    I wonder what happens to all the heat that's being taken up by the oceans. Is any of it released - and if so, how? Evaporation and heat needed to melt polar ice come to mind as possibilities. Or is it going to stay there, forever warming the oceans, and the oceans increasing in temperature forever.

    The next thing is of course the question of how it affects the deeper oceans. Are those layers also warmed up - for example thanks to ocean currents mixing the water of the world's oceans?

    • by jellomizer ( 103300 ) on Monday October 06, 2014 @06:07AM (#48071811)

      The ice caps which are melting are taking some of the heat. Evaporating water will cool it down too. The currents moving the water to cooler areas will go to warm up the cold areas. That it is called global climate change. Not global weather change the whole system is changing from the imbalance.

    • I wonder what happens to all the heat that's being taken up by the oceans.

      Ah - the only intelligent comment on this issue on /. so far, on this fine morning. This is very likely what climatologists are thinking about too; heat, being energy, doesn't disappear, so it must be somewhere. My guess is that it isn't perhaps so much about where the heat went as it is about by how much the temperature increase has been underestimated - IOW, that the water was somewhat colder before than what we guessed. That is of course one of our problems: when we don't have enough observations, we hav

    • Re: (Score:3, Informative)

      by Sqr(twg) ( 2126054 )

      Evaporation increases exponentially with temperature, so even with a lot of extra heat going into the oceans, the change in surface temperature will not be that large. Since water vapor is lighter than air, the extra evaporation will also increase air circulation above the sea, cooling it even further.

      So, don't expect to notice any difference in tempearture when you go swiming. The only change that you might notice is melting polar caps, and a massive increase in tropical hurricanes.

      • With such temperature changes measured in the tenth of degrees, I don't expect to suddenly have a sea warm enough to swim in during winter time :)

      • Re: (Score:2, Interesting)

        by danbert8 ( 1024253 )

        Ahh yes, we've just established that the oceans have been warmer than we expected. And just around the same time we've had a recent minimum of severe hurricanes. Climate change or not, you cannot predict severe weather patterns. Anti-deniers like to attribute every negative event to climate change and none of the positive events. Maybe a warmer planet will have less severe weather if the air temperature is closer to the water temperature as it is the differential that causes severe weather.

        • by wbr1 ( 2538558 )
          An interesting question. Perhaps hurricane formation is down because the temperature gradient between areas of the ocean is decreasing? Maybe it is not warm water only, but the difference between the hot and cold areas that are a large factor in development/strength of large storms?
        • by Sqr(twg) ( 2126054 ) on Monday October 06, 2014 @09:15AM (#48072579)

          And just around the same time we've had a recent minimum of severe hurricanes.

          By which you mean that we had no category five hurricane last year? That's just a consequence of the fact that there is less than one per year on average, and the number must be integer. (If you do the count per decade, then 2000-2009 had the highest number (8) of category five hurricanes in recorded history, but this number is still too small to draw any statistically significant conclusions from.)

          There is more information in the data on category four hurricanes. I found this table of category 4 hurricane statistics on wikipedia [wikipedia.org]

          Period Number Number per year
          1851–1900 13 0.26
          1901–1950 29 0.58
          1951–1975 22 0.88
          1976–2000 24 0.96
          2001–2012 19 1.6

          • Interestingly, you randomly choose years to fit your criteria.1851-1900 = 49 years. 1901-1950 = 49 years, 1950-1975 = 25 years, 1976-2000=24 years, 2000-2012 = 12 years ...

            See the problem yet? Of course not, the problem doesn't fit the narrative, so we ignore the problem .

            • by thrich81 ( 1357561 ) on Monday October 06, 2014 @11:28AM (#48073625)

              Actually I don't see any problem in the OPs statistics as stated. If you combine the 1951-1975 entries and the 1976-2000 entries you get a 50 year period, just like the two periods before. And its total number of cat 4 hurricanes is 46, well over the totals for the 50 year periods before, which perfectly fits his narrative. It isn't uncommon to reduce the intervals in statistical aggregations when things start changing more rapidly. In this case the OP did it such that we can easily recreate equal sized bins. By the way, those periods he used are 1851 to 1900 = 50 years, 1901 to 1950 = 50 years, 1951 to 1975 = 25 years, 1976 to 2000 = 25 years, not 49, 49, 25, 24 as you stated. The statistics here are pretty simple, not much room to manipulate or complain about them. Looks like a trend to me.

            • by Sqr(twg) ( 2126054 ) on Monday October 06, 2014 @12:59PM (#48074287)

              I did not chose the years. This was a quick copy-paste from Wikipedia. I suppose they picked the intervals so that the number of observations in each bin would be about 20, which implies a standard deviation uncertainty of about 4.5 hurricanes in each interval.

              But since you didn't like that table, here's one just for you:

              1851–1900 13 0.26
              1901–1950 29 0.58
              1951–2000 46 0.92

              (Each of the above intervals is 50 years, not 49. I haven't found any statistics on the correlation between being a climate change skeptic and being unable to do simple math, but I'm sure it would be interesting.)

              Now, if you really wanted to raise a valid objection, you would point out that weather satellites did not exist until the 1960:s, and that the number of severe hurricanes might have been underestimated prior to that.

        • by dywolf ( 2673597 )

          Actually no. You completely misstated it.

          The scientific viewpoint is that "No single weather event can be definitively tied to climate change", because the causal link has not yet been made definitively. But at the same time, weather events are happening more often. The phrase is "“statistically speaking, we’re seeing more extreme weather events, getting even more extreme over time”. And weather "seasons" are changing in duration; some starting earlier and lasting longer, others starting l

        • by dywolf ( 2673597 )

          essentially we're tlaking about playing the game of "what if?".
          as in, "what if X was different? would Y have still have happened?", and that's a difficult link to make.

      • The cycle continues. Heat rises with evaporation but the air saturates with moisture rather quickly. Cloud formation results and slows the radiation, Heat gets trapped by the clouds. Wind moves both the clouds and moisture away, over land someones parade or wedding gets ruined or if lucky framing gets it's rain. It's a rather large heat engine the cycles itself continuously day and night. Speaking of night, with longer winter night facing means more time for radiation. Summer has more time for energy absorp
      • Re: (Score:3, Insightful)

        " and a massive increase in tropical hurricanes."

        They have been saying this for YEARS now, and there hasn't been a major hurricane in how many years?

        It is predictions and statements like this that have people like me scratching our heads. None of the predictions of doom have happened. Polar Bears are not drowning either. When people are caught lying, repeatedly, people stop believing them. This is what happens when people stop reading fairy tales and start creating them using "Science" as a backdrop.

    • New research suggests that the upper layer of the ocean has warmed more than had been thought previously while the deeper ocean has cooled rather than warmed in recent years.

      http://judithcurry.com/2014/10... [judithcurry.com]

  • 90% ? (Score:3, Informative)

    by ishmaelflood ( 643277 ) on Monday October 06, 2014 @05:48AM (#48071763)

    So given that conventional atmosphere models have ignored this to date, if the oceans are storing 90% of the excess heat, why aren't the conventional models showing temperature rises 10 times as great as what is observed, say 5-10 deg C?

    Either the summary or the article are slack in the extreme.

    • by mwvdlee ( 775178 )

      Because oceans have ALWAYS been storing excess heat.
      This finding impacts the ocean's heat storage behaviour throughout it's entire existance, not just since humanity.
      It's the interpretation of the summary and article that is slack in extreme.

    • So to explain more fully. I looked at the article and didn't see a mention of any atmospheric model. Which is not a surprise because atmospheric models haven't been used for prediction for years - if ever. GCM models certainly take into account ocean heat absorption and indeed the 90% is the current estimate - oceans are expected to absorb 90% of the warming. The article suggests this estimate is low ( and hence the estimate of s sensitivity is low ) but it could not be an order if magnitude out (as you imp
    • by Bengie ( 1121981 )
      There may be 10x more energy coming in than we expected, but there's a heck of a lot more mass absorbing the extra energy than expected. We're not seeing a large temperature increase because of the huge mass of the ocean, which (Mass of Ocean * specific heat)/(Mass of Atmosphere * specific heat) = ~66. The extra energy isn't enough to increase the temperature much, but it is still a lot of energy, meaning more stuff like hurricanes or ice melts.
  • they estimate past heat tallies were 48% to 152% too low

    I still don't understand if this discovery is a good or a bad thing ... but can someone please explain to me how you can estimate that a value is more than 100% "too low"?

    I would assume that you would measure heat absorbtion in BTU or Watts, or something that can't go negative (ie, not in degrees Farenheight, which is a temperature, not a measure of stored heat)

    • but can someone please explain to me how you can estimate that a value is more than 100% "too low"?

      48-150% too low means you have to multiply the old answer by between 1.48 and 2.50 in order to get the correct answer.

      IOW you have to increase the old answer by 48% to 150%. Or, colloquially, the old answer was too small. By 48% to 150%.

    • "The results suggest that previous estimates of the heat stored in the upper 700 meters of the ocean since 1970 have been too low. In the Southern Ocean in particular, they estimate past heat tallies were 48% to 152% too low." Let's start with the 48% number. What do we need to get the new estimate from the old estimate? Multiply the old estimate by 0.48 and add that to the old estimate. Simplified, just multiply the old estimate by (0.48 +1). For the 152% number, it would be a factor of 2.52.

  • This is very confusing. Did they find evidence that this is happening? Or did they find something that "MIGHT" "SUGGEST" that something has happened?

    Because if the former... great. I love it when science figures something out.

    If not... then while that is still good that they're looking into these things... it does literally nothing for the public debate about AGW. A "might" "suggest" gets us no where until that is refined into something more definite.

From Sharp minds come... pointed heads. -- Bryan Sparrowhawk