Tuesday, December 17, 2013

New paper shows climate models have exaggerated ocean warming by 66,590 Hiroshima bombs per day

An erratum published today in Climate Dynamics shows that climate models have exaggerated heat accumulation of the oceans by about 66,590 Hiroshima bombs per day vs. observations over the past ~50 years. That's indeed a travesty of a lot of "missing heat."

According to the corrected 700 meter heat content data below, observations show about 54% less heat accumulated than predicted by climate model simulations. Observations show the global oceans have warmed only 0.09C over the past 55 years, which demonstrates the IPCC has exaggerated the effect of CO2 on the climate by a factor of at least 5 times.

According to the authors, "the historical [model] simulations still overestimates the heat content trend over this last time period [1970-2005], which could be related to the too large climate sensitivity" to CO2.

Math:
  • Observations [red line in graph below] show a heat content increase of ~13e+22 J from 1956-2004
  • Models [black line in graph below] historical simulation predicted a heat content increase of ~20e+22 J from 1956-2004
  • Models therefore exaggerated heat increase by ~7e+22J [54%]
  • One Hiroshima bomb = 6e+13 J
  • 7e+22/6e+13 = 1,166,666,666 extra Hiroshima bombs exaggeration by models over past 48 years, or 66,590 excess Hiroshima bombs per day
  • It is left to the reader to work out the number of kitten sneezes this exaggeration equates to



In Fig. 3 of the published version, the heat content was integrated down the 200 m only in the model simulations, thereby biasing the comparison with the data, which are themselves integrated down to 700 m. The new figure shows the heat content integrated down to 700 m both in the simulations and in the data. This correction generally improves the comparison of the model simulations with the observations of heat content for the most recent period, especially in the Atlantic basin.

Corrected Fig. 3: Heat content from Levitus et al. (2009) with slight recent improvements in red (cf.http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT), from the nudged simulations in blue and from historical simulations in black expressed in 1022 J. a for the global ocean, b over 30–70°N in the Atlantic. The reference period is 1961–1990, and a 3-year running mean has been applied to all the data. The error bar for historical and nudged simulations corresponds to two standard deviations computed for each five-member ensemble. The red vertical lines represent the years with a large eruption, i.e. the Mount Agung in 1963, El Chichon in 1982 and Pinatubo in 1991

The corrected numbers in section 3.1, concerning the computed trends for global heat content from Fig. 3 for the period 1955–2005, are 113.1 TW (r2 = 0.98) in the nudged simulations and of 129.5 TW (r2 = 0.84) in the historical simulations as compared to the trend of 69.5 TW (unchanged, r2 = 0.70) in the data. The agreement is therefore lower over this time period than suggested in the published version, but it increases if computed over the more recent time frame 1970–2005 with 115.5 TW (r2 = 0.96) in the nudged [fudged] simulations, 189.0 TW (r2 = 0.96) in the historical simulations and 108.6 TW (r2 = 0.83) in the data. While the historical simulations still overestimates the heat content trend over this last time period, which could be related to the too large climate sensitivity in IPSL-CM5A-LR (Dufresne et al., this issue), the nudging [fudged model] leads the heat content to be closer to the observations.
We believe that this error may not modify the main messages of the paper, which are more related to the impact of volcanoes on the AMOC.

7 comments:

  1. http://hockeyschtick.blogspot.com/2013/12/cooks-skeptical-science-new-scare.html

    ReplyDelete
  2. http://bobtisdale.wordpress.com/2013/12/18/if-manmade-greenhouse-gases-are-responsible-for-the-warming-of-the-global-oceans/

    ReplyDelete
  3. So how come glaciers all across the globe have been shrinking dramatically over, say, the past century?

    ReplyDelete
    Replies
    1. That's what happens during an interglacial - ice continues to melt until the next ice age occurs. The Little Ice Age ended 150 years ago and was the coldest period of the past 10,000 years, so yes, glaciers are melting faster now than 150 years ago. The solar maximum in the latter 20th century is the driver, not man.

      During the last interglacial [Eemian], sea levels were 31 feet higher than the present and Greenland 8C warmer than the present. There is no evidence that the current interglacial is any different.

      Delete
  4. Gail Combs says:

    Long term we are in a COOLING trend.
    SEE GRAPH: http://i.snag.gy/BztF1.jpg or read these peer-reviewed papers:

    Temperature and precipitation history of the Arctic 2010
    Miller et al
    Institute of Arctic and Alpine Research and Department of Geological Sciences, University of Colorado, USA et al

    …. Solar energy reached a summer maximum (9% higher than at present) ~11 ka ago and has been decreasing since then, primarily in response to the precession of the equinoxes. The extra energy elevated early Holocene summer temperatures throughout the Arctic 1-3°C above 20th century averages, enough to completely melt many small glaciers throughout the Arctic, although the Greenland Ice Sheet was only slightly smaller than at present. Early Holocene summer sea ice limits were substantially smaller than their 20th century average, and the flow of Atlantic water into the Arctic Ocean was substantially greater. As summer solar energy decreased in the second half of the Holocene, glaciers re-established or advanced, sea ice expanded…

    A more recent paper looking at glaciers in Norway.

    A new approach for reconstructing glacier variability based on lake sediments recording input from more than one glacier January 2012
    Kristian Vasskoga Øyvind Paaschec, Atle Nesjea, John F. Boyled, H.J.B. Birks

    …. A multi-proxy numerical analysis demonstrates that it is possible to distinguish a glacier component in the ~ 8000-yr-long record, based on distinct changes in grain size, geochemistry, and magnetic composition…. This signal is …independently tested through a mineral magnetic provenance analysis of catchment samples. Minimum glacier input is indicated between 6700–5700 cal yr BP, probably reflecting a situation when most glaciers in the catchment had melted away, whereas the highest glacier activity is observed around 600 and 200 cal yr BP. During the local Neoglacial interval (~ 4200 cal yr BP until present), five individual periods of significantly reduced glacier extent are identified at ~ 3400, 3000–2700, 2100–2000, 1700–1500, and ~ 900 cal yr BP….

    The authors of BOTH papers simply state that most glaciers likely didn’t exist 6,000 years ago, but the highest period of the glacial activity has been in the past 600 years. This is hardly surprising with ~9% less solar energy.
    MORE:

    Holocene temperature history at the western Greenland Ice Sheet margin reconstructed from lake sediments – Axford et al. (2012)
    “….As summer insolation declined through the late Holocene, summer temperatures cooled and the local ice sheet margin expanded. Gradual, insolation-driven millennial-scale temperature trends in the study area were punctuated by several abrupt climate changes, including a major transient event recorded in all five lakes between 4.3 and 3.2 ka, which overlaps in timing with abrupt climate changes previously documented around the North Atlantic region and farther afield at ∼4.2 ka…..”
    http://www.sciencedirect.com/science/article/pii/S0277379112004209

    ….the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence….
    http://web.pdx.edu/~chulbe/COURSES/QCLIM/reprints/LisieckiRaymo_preprint.pdf (NOTE: pdf has been removed from internet)

    Abstract
    …..We therefore conclude that for a period in the Early Holocene, probably for a millenium or more, the Arctic Ocean was free of sea ice at least for shorter periods in the summer……
    http://adsabs.harvard.edu/abs/2007AGUFMPP11A0203F

    Abstract
    …..Arctic sea ice cover was strongly reduced during most of the early Holocene and there appear to have been periods of ice free summers in the central Arctic Ocean……
    http://www.sciencedirect.com/science/article/pii/S0277379110003185

    ReplyDelete
  5. http://hockeyschtick.blogspot.com/2013/07/paper-finds-alps-were-nearly-ice-free.html

    ReplyDelete
  6. http://wattsupwiththat.com/2014/01/01/ocean-heat-content-variations-satellites-vs-oceanographers/

    ReplyDelete