Tuesday, November 19, 2013

Hansen's NASA GISS data confirm the Arctic was warmer from 1920-1940 and cooled 1940-2000

A 2005 paper published in the ICES Journal of Marine Science shows NASA GISS data demonstrating that 20th century Arctic temperatures peaked between 1920 to 1940, followed by a decline over the remainder of the 20th century. According to the authors, 
"From approximately 1920 to 1940, North Atlantic Waters from Greenland to Norway warmed significantly, by as much as 3–4°C (TÃ¥ning, 1948). Although the causes of this event are not well understood, there is no doubt of its authenticity or widespread occurrence in temperature records (Figure 7)." and
"a major warming event in Icelandic and Greenland waters between 1920 and 1940 was extensively documented (e.g. Sæmundsson, 1932; Ahlmann, 1948; Lysgaard, 1948)."

Figure 7
Surface air temperatures for (a) St. John's, Newfoundland; (b) Nuuk, Greenland; (c) Akureyi, Iceland; and (d) Bodo, Norway. Solid line is a decadal moving average. Data from NASA database at Goddard Space Center [James Hansen's former employer GISS], New York.
The paper corroborates a new paper finding ice core proxy temperatures and 4 meteorological datasets show that 20th century Arctic temperatures peaked between 1920-1940 and cooled to the end of the record in 2000. 

This is the opposite pattern to what would be expected if man-made greenhouse gases were the cause, as even alarmists claim the increase in greenhouse gases has only had a significant effect since 1950. Instead, both of these papers demonstrate 20th century Arctic temperatures peaked between 1920-1940, followed by a declining trend to the end of the record in 2000.

Both papers demonstrate Hansen's red crayon for the Arctic amounts to nothing more than cherry picking baseline dates for comparison, omitting the hottest years from 1920-1940 as the baseline, along with upjusting station data and inappropriate extrapolations from warmer stations further south.

Hansen's red crayon can be used much more in the Arctic if the cherry-picked baseline is the global cooling scare years between 1951-1980, as Hansen did in the above figure. If the Arctic's warmest years of the 20th century between 1920-1940 were used as the baseline instead, the Arctic would show little temperature change or possibly even cooling.

On distributional responses of North Atlantic fish to climate change

G.A. Rose

Changes in fish distribution and climate in the North Atlantic have been observed for millennia by seafaring peoples, chronicled in many historical anecdotes, and recently studied systematically. For temperate to Arctic North Atlantic fish, a literature compendium of limits of temperature, salinity, and depth during feeding and spawning was used to investigate factors that influence distribution. Latitude and depth were negatively correlated with species number and density. Peak numbers of species feed at 0–4°C, but spawn at 2–7°C and salinities of 32.5–33.5. Principal components of feeding depths and temperatures suggested four groups of species: (i) small pelagics characterized by shallow habitat and cooler temperatures; (ii) most groundfish in deeper and warmer waters; (iii) warm-water large pelagics; and (iv) deepwater species. Spawning temperatures, salinities, depths, and timing produced groupings consistent with feeding components for pelagics, but differing for distant migrants such as tunas. Principal components (PCA) of spawning characteristics explained 56% of the variance in species resilience (doubling time), while PCA of feeding characteristics explained only 23%. We infer that the small pelagics capelin (Mallotus villosus) and herring (Clupea harengus) react strongly and quickly to climate change because of their physiological limits and potential for fast population growth. Verification comes from Icelandic and Greenland waters, which warmed considerably during 1920–1940, and where capelin, herring, cod (Gadus morhua), and other species shifted north very quickly.


  1. jim Steele says:
    November 19, 2013 at 4:58 pm

    There several other studies to support the conclusion Arctic temperatures have not risen since the 50s.

    The greatest loss of Arctic sea ice has been due to warm water intrusions in the Barents and Kara (Figure 1 http://landscapesandcycles.net/antarctic-sea-ice–climate-change-indicator.html)
    The behavior of the glaciers on islands in that region provide further support to this paper’s conclusion of no warming since the 50s. Researchers wrote, “Recession of tidewater calving glaciers on north Novaya Zemlya in the first half of the twentieth century was relatively rapid (.300 m yr-1), consistent with post-‘Little Ice Age’ warming documented by a 122-year instrumental record from Malye Karmakuly. The glaciers completed 75 to 100% of the net twentieth-century retreat by 1952. Between1964 and 1993 half of the studied glaciers were stable; the remainder retreated modest distances of ,2.5 km.” read 796. Zeeberg, J. and Forman, S. (2001) Changes in glacier extent on north Novaya Zemlya in the twentieth century. The Holocene, vol 11, p. 161–175.

    Tree ring and instrumental data from northern Scandinavia are also in agreement with the warmest peaks in 40s.


    read Esper, J. et al. (2012) Variability and extremes of northern Scandinavian summer temperatures over the past two millennia. Global and Planetary Change 88–89 (2012) 1–9.

    Much of any warming is due to ventilation of heat from ice free waters. HOwever over ice covered western Arctic Ocean and based 27000 dropsondes and drifting Russian ice stations researchers reported “In particular, we do not observe the large surface warming trends predicted by models; indeed, we detect significant surface cooling trends over the western Arctic Ocean during winter and autumn. actually showed a cooling trend in the 80s and 90s” Kahl, J., et al., (1993) Absence of evidence for greenhouse warming over the Arctic Ocean in the past 40 years. Nature 361, 335 – 337.

    Not much observational data to support warming since the 50s!

  2. http://www.kaltesonne.de/?p=13862