New Study: When You Account For The Oceans, Global Warming Continues Apace

There’s a new study out (and unfortunately gated) from European researchers in Nature Climate Change adding to the case that the oceans have absorbed much of the effect of global warming since 2000.

One of the more popular recent arguments among climate change deniers is that temperatures have not increased since roughly 2000, even as we’ve continued dumping carbon emissions into the atmosphere. The claim falls apart in several different ways. But one of the main ones is that it simply fails to account for the fact that the oceans are themselves part of the planetary ecological system being affected by global warming. And as Reuters reported, one of the findings of the study is that surface temperatures could begin accelerating again if that heat moves back out of the oceans:

Experts in France and Spain said on Sunday that the oceans took up more warmth from the air around 2000. That would help explain the slowdown in surface warming but would also suggest that the pause may be only temporary and brief.

“Most of this excess energy was absorbed in the top 700 meters (2,300 ft) of the ocean at the onset of the warming pause, 65 percent of it in the tropical Pacific and Atlantic oceans,” they wrote in the journal Nature Climate Change.

Lead author Virginie Guemas of the Catalan Institute of Climate Sciences in Barcelona said the hidden heat may return to the atmosphere in the next decade, stoking warming again.
“If it is only related to natural variability then the rate of warming will increase soon,” she told Reuters.

Several previous studies, including Balmaseda et al. (2013) and Nuccitelli et al. (2012) used a combination of improved data collection and new computer modeling to reach essentially the same conclusion. Furthermore, they concluded that anywhere from 30 to 40 percent of the warming over the last ten or so years has occurred in the ocean depths below 700 meters — depths that aren’t always accounted for.

On top of that, there was an unusually high level of La Niña events since 2000, which also covered up some of the warming. La Niña and El Niño are the two poles of the Southern Oscillation, a natural cyclical process that brings cold and warm water, respectively, upwelling to the surface of the equatorial Pacific Ocean. The cold waters accompanying the La Niña oscillation in 2008 were the strongest seen since 1999, and drove sea-surface temperatures as much as two degrees colder than they otherwise would be.

The Southern Oscillation: A positive index corresponds to La Niña, and a negative one corresponds to El Niño.

All told, the oceanic temperature increase accounts for much of the “missing heat” — warming that was anticipated based on the scale of carbon emissions, but that standard measurements couldn’t pick up — identified by Kevin Trenberth, one of the authors of the previous studies. It also means that, again contrary to some claims, the Earth’s climate sensitivity probably isn’t lower than previously thought. More likely, we’ll simply see less short-term warming than scientists have anticipated, but offset by greater long-term warming and more rapid sea level rise.

“Global warming is continuing but it’s being manifested in somewhat different ways,” Trenberth told Reuters, adding that the pause in surface warming could last 15 to 20 years. Meanwhile, “recent warming rates of the waters below 700 meters appear to be unprecedented.”

21 Responses to New Study: When You Account For The Oceans, Global Warming Continues Apace

  1. Ed Leaver says:

    One might suggest that “unusually high level of La Niña events” not only cover up some surface warming — they also play an important role in transferring heat from the atmosphere into the ocean. (Rate of transfer being proportional to surface temperature differential.)

  2. Jack Burton says:

    I thought that much of the last 10 years has seen unusually long events of La Nina. Like back to back events. What can we expect when the El Nino event returns? Is it not true that El Nino returns stored heat back to the atmosphere?
    It is not as if last summer in the USA was anything but blisteringly hot. Air temps were off the chart in some areas.

  3. for Earth says:

    Isn’t this bad news re methane hydrates?

  4. Mulga Mumblebrain says:

    Perhaps these are no longer best described as La Nina events. Perhaps the rapid climate destabilisation means that ENSO etc have become redundant, quite soon after we discovered them.

  5. Solar Jim says:

    This headline understates our condition. The word “apace” implies a steady rapid rate (since the new century in this study) rather than the reality of rapid acceleration.

  6. Merrelyn Emery says:

    Yes Solar Jim, language is important and should be used precisey and accurately, ME

  7. Bhan says:

    El Niño and La Niña make temperatures change from year to year. In the long run, the Earth is steadily warming.

  8. DJK says:

    Here is a great piece (with video) about related research done at Boston University:

  9. SkyHunter says:

    Depends. Warmer water temperature cold destabilize the clathrates, but as the oceans warm, they expand, and sea levels ris, so the increase in pressure could offset the increase in temperature.

  10. KK Aw says:

    Using surface air temperature as an indicator of global warming is as silly as it gets. Air temperature is moderated by the presence of water. With no water, the temperature can rise significantly during the date and falls drastically during the night. Yes, in a drought, the air temperature can rise considerably but that does not mean there is more energy in the system. In the tropics, with forested areas, the temperature is unlikely to rise above 35 degrees celsius because of evapotranspiration. Another example is that the human body can maintain a near-constant body temperature through evaporation.

    Global warming, if any, is about atmospheric energy and the energy stored in the oceans as this article is pointing out. If we want to understand our climate, we should not be using temperature as a criterion.

  11. Evan Jones says:

    Yet globally, 2012 was rather a ho-hum year.

  12. Joan Savage says:

    When Climate Progress cites a peer-reviewed study by name, I strongly prefer that CP’s hyperlink be to the peer-reviewed article.

    Leaving it to a reader to wade through an older blog or two to find the actual citations is a bit like the annoying practice that news media have of putting advertising above the banner. In academia, using a secondary source is lame.

    I far prefer Joe Romm’s usual practice of listing previous relevant blogs at the base of the article. May that practice continue, please!

  13. Superman1 says:

    You’re right; spelling ‘precisely’ correctly would be a start!

  14. Superman1 says:

    Technically, you’re correct. In myriad fields, many metrics, and metric ‘signatures’ (weighted combinations of metrics) are required to describe the phenomena completely. This is fine for communications among research specialists. However, to communicate with the general public, the other end of the spectrum is required. One metric that is part of their everyday experience may be all they can handle. For climate change, temperature is not all that bad, given we recognize its severe limitations.

  15. Alan Frederick says:

    The word “apace” actually means “rapidly”,”swiftly”. I do not believe there is any connotation of steadiness.

  16. john atcheson says:

    I’m a little confused — 9 of the ten warmest years on record have all occurred since 2000 (1998 is the exception), so I don’t think it’s accurate to talk of a “pause” in warming. It doesn’t even look like the rate of increase in warming has slowed down.

    So are we talking about a gap between projected warming vs. actual? Even that depends upon which projections you pick.

    We need to rethink how we talk about this or we’ll see headlines in WPWT taking the discussion out of context, and fueling confusion and doubt.

  17. Jim Baird says:

    In moving surface heat to the depths, Nature is doing, without benefit to us, what we should be doing to produce all of the energy we can use with OTEC.

  18. Jim Eberle says:

    Shouldn’t there be a natural increase in the frequency of La Nina’s as warming progresses? Warming has caused an intensification of the semi-permanent subtropical highs, also called “Hadley Cells”, which seasonally get stronger as summer approaches. A stronger Hadley Cell over the north Pacific would intensify the Trade Winds between the equator and 25 Degrees north latitude. This in turn would promote upwelling of cold water along the Pacific coast of Peru, Equador, and Columbia. Warm waters driven westward would intensify the Monsoon over the far western tropical Pacific. I expect a nearly permanent La Nina to evolve with time.

  19. Elizabeth Woodworth says:

    For the economy to work, people need the truth so alternatives to oil can generate jobs. This April essay (Part I) presents new and startling evidence about the three assassinations of the 1960’s, and how they have stunted our knowledge of history, and thus our wisdom in governing. The unseen forces that were at work in the sixties have never been opposed and have been retarding an effective media and citizen response to the facts about climate change.
    Part II: The whole Keystone debate has nothing to do with jobs, investigative reporting, or an informed public — and everything to do with narrow industry profits, election campaign chests, and industry-backed media fog. As this April 7 essay shows, an enormous gulf exists historically between scientific consensus on climate change and public awareness, with the media giving equal time to believers and deniers.

  20. David Lewis says:

    Balmaseda 2013 cites Levitus 2012 “World Ocean heat content and thermosteric sea level change” as a prime data source, calling it “the most recent estimate of the ocean warming”. Levitus in turn cites Kouketsu 2011, “Deep Ocean heat content changes estimated from observation and reanalysis product and their influence on sea level change“.

    Levitus is too cautious to use the Kouketsu result, saying “we simply do not have enough… data from depths exceeding 2000 m available”, but noted: “If the results of Kouketsu et al 2011 are correct, this would mean a contribution of 1.6 x 10 to the 22nd power J” that Balmaseda 2013 would have otherwise had to incorporate into their (re)analysis.

    That amount of heat, suspected to be accumulating below 2000m and not included in anyone’s calculation of the planetary energy balance, is about 8% of the total ocean heat content as described by Balmaseda 2013, or so my back of the envelope calculation indicates.

    An unaccounted for amount of heat storage of this magnitude would appear to be significant, i.e. it is more than the entire amount that is accumulating in the atmosphere.

  21. Klon says:

    Yes, oh ho hum, just the hottest La Nina year on record (or second or third, depending on how you look at it.) Move along…