Varotsos et al: Evidence for two abrupt warming events of SST in the last century

Posted: June 14, 2013 by tallbloke in Analysis, Dataset, Natural Variation, solar system dynamics

Apart from the obligatory nod to AGW in the final sentence of this abstract, this paper looks like a promising roundup of the natural factors involved in the ~60yr climate cycle, with the notable exception of geomagnetic considerations.

Evidence for two abrupt warming events of SST in the last century
Costas A. Varotsos, Christian L. E. Franzke, Maria N. Efstathiou, Andrei G. Degermendzhi

Theoretical and Applied ClimatologyJune 2013

We have recently suggested that the warming in the sea surface temperature (SST) since 1900, did not occur smoothly and slowly, but with two rapid shifts in 1925/1926 and 1987/1988, which are more obvious over the tropics and the northern midlatitudes. Apart from these shifts, most of the remaining SST variability can be explained by the El Niño Southern Oscillation and the Pacific Decadal Oscillation (PDO). Here, we provide evidence that the timing of these two SST shifts (around 60 years) corresponds well to the quasi-periodicity of many natural cycles, like that of the PDO, the global and Northern Hemisphere annual mean temperature, the Atlantic Multi-decadal Oscillation, the Inter-Tropical Convergence Zone, the Southwest US Drought data, the length of day, the air surface temperature, the Atlantic meridional overturning circulation and the change in the location of the centre of mass of the solar system.

In addition, we show that there exists a strong seasonal link between SST and ENSO over the tropics and the NH midlatitudes, which becomes stronger in autumn of the Northern Hemisphere. Finally, we found that before and after each SST shift, the intrinsic properties of the SST time series obey stochastic dynamics, which is unaffected by the modulation of these two shifts. In particular, the SST fluctuations for the time period between the two SST shifts exhibit 1/f-type long-range correlations, which are frequently encountered in a large variety of natural systems. Our results have potential implications for future climate shifts and crossing tipping points due to an interaction of intrinsic climate cycles and anthropogenic greenhouse gas emissions.

http://link.springer.com/article/10.1007%2Fs00704-013-0935-8

Comments
  1. Kon Dealer says:

    It read quite well up to this point “Our results have potential implications for future climate shifts and crossing tipping points due to an interaction of intrinsic climate cycles and anthropogenic greenhouse gas emissions.”
    Is the last sentence the required genuflection to Church of AGW to get published, a plea for more grant money, or both?

  2. oldbrew says:

    ‘Apart from these shifts, most of the remaining SST variability can be explained by the El Niño Southern Oscillation and the Pacific Decadal Oscillation (PDO).’

    That virtually rules out any anthropogenic causes 🙂

  3. tallbloke says:

    Don, yes, yes, and yes.

  4. Paul Vaughan says:

    Evade the paywall :

    Belolipetsky, P.V.; Bartsev S.I.; Degermendzhi A.G.; Hsu, H.-H.; & Varotsos C.A. (2013). Empirical evidence for a double step climate change in twentieth century.
    http://arxiv.org/ftp/arxiv/papers/1303/1303.1581.pdf

  5. tchannon says:

    Well done Paul, I’d not got around to looking.