Moby Dick's Revenge
by

John L. Daly

Another example of bad climate science, fully peer reviewed and published in a top journal -

de la Mare, William K., 1997, "Abrupt mid-twentieth-century decline in Antarctic sea-ice extent from whaling records", Nature, vol.389, pp 87-90, 4 Sept 97

In an attempt to demonstrate that global warming was attacking the Antarctic ice, Southern Ocean whaling records held by the Bureau of International Whaling Statistics, Oslo, were analysed by de la Mare (1997) to statistically determine the latitude position of sea ice fringes during the summer whaling seasons from 1934 to 1992.

According to de la Mare, whaling occurred in three distinct phases from 1931-1940, 1945-1958 and 1972-1992, and his paper concluded that Antarctic sea-ice had receded by 2.8 degrees latitude (168 nautical miles) between 1958 and 1972 - at a time when there were no fleets in the area, or satellites, to record this momentous event. This conclusion was arrived at by statistically analysing the positions of the fleets in the pre-1958 phases of whaling with those recorded post-1972. It was assumed that hunting for certain whale species always occurred adjacent to the ice fringe, which then becomes a proxy for sea ice positioning.

De la Mare analysed a database (Australian Antarctic Division, 1997) containing 42,258 records of whales caught, with associated dates, fleet positions, and whale species. However, a random sample inspection of the records in the database reveals several problems with the shrinkage hypothesis not apparent in the broader statistical analysis.

Firstly, during the late 1940’s to early 1950s, hunting was common right inside the Ross Sea to latitude 77S at a time when the ice fringe was claimed to be 168 nautical miles further north than today. Many database records showed whaling activities this far south. If the ice was more extensive at that time, how could such hunting, a mere 780 nautical miles from the South Pole, have been undertaken?

Secondly, a significant difference between 1931-1958 and 1972-92 records was in the accuracy of the fleet’s noon positions. The latter were accurate to 0.01 deg. latitude and longitude (employing satellite navigators), while the 1931-58 records were only entered to the nearest degree of latitude and longitude, (ie. 60 nautical miles) using celestial positioning from sextant readings, or dead reckoning in the absence of sun/star readings. Anomalies are clearly evident during the earlier phase as some ships indicated journeys which were well in excess of their normal speed of 12 knots. In one case, a fleet recorded itself as travelling about 670 nautical miles in only 24 hours (database ID 81-82), while another was somehow positioned on the Antarctic continent itself ! (ID 709).

Thirdly, de la Mare assumed that all whale species (except sei) were hunted near the ice fringe and while this is certainly true of the 1972-92 phase of minke whaling, it is not always true of the 1931-1958 phases. In the earlier period of whaling a range of species was hunted, many in open water and a considerable distance from the ice (Bastesen, 1997). The database also suggest this was common practice as many vessels were recorded as hunting a single area for many days or weeks, only to suddenly sail up to 350 nautical miles due south or north in only one or two days to another hunting ground (e.g. database IDs 81-82, 89-90, 94-95, 207-208, 222-223, 11569-11572). Rapid southerly shifts in hunting grounds is not possible if the initial position is at the ice edge, particularly as there was no satellite navigation, no satellite imagery of the ice, no spotter helicopters or other technologies available to the pre-1972 whalers to allow them to sail into ice openings (polynyas) with safety. Even radar (available from the 1950s) is inefficient near ice due to severe sub-refraction of the signal, and the poor radar reflectivity of low-lying ice (personal observation).

Fourth, positions recorded by 1931-58 whalers would have been compromised by the presence of overcast cloud common in summer at very high latitudes (Henderson-Sellers, 1984), forcing the ships to rely for many days on dead reckoning, concealing quite large errors over time due to high wind and drift. Even when celestial navigation was possible, the phenomenon of enhanced optical refraction of light, common in high latitudes during atmospheric layer inversions (Umland 1997) can introduce uncorrectable sextant errors to give a slightly lower latitude reading than the real latitude of the observer. In other words the sextant-based positions would result in recorded noon positions further north than the fleet's actual position. Since the latter phase of whaling would have positions determined accurately by satellites, the impression would be one of a southerly shift of whaling zones and consequently of the ice fringes.

Finally, during the 1958-72 period when there was no whaling at the ice fringe, Japanese fleets still hunted whales in the open southern oceans at high latitudes and recorded sea surface temperatures (SST). According to Mierzejewska et al (1997), these Japanese records indicate no significant changes in SST for the period 1946-84. Had the sea ice really shrunk by such a massive amount as suggested by de la Mare, this would have certainly made an impact on SSTs.

But most amazingly of all, this all happened when no-one was looking - no whalers, no satellites, no regular shipping. As soon as satellites were in the sky and whaling resumed in 1972, the sea ice chose to remain still, neither expanding nor shrinking (apart from normal seasonal movement), even through the alleged `warming' of the 1980s and 1990s. It seems to have occurred to no-one, neither among the peer reviewers or the `Nature' publishers that this "now you see it, now you don't" piece of climatic conjuring was entirely a product of auto-suggestive misinterpretation of questionable data.

Conclusion

The de la Mare paper, fully peer reviewed and published in `Nature' is a classic example of how questionable science easily slips through the current mindset created by the global warming hysteria where normal scientific standards are readily compromised provided the orthodoxy of global warming is reinforced. It also represents yet another failure on the part of the much-vaunted peer review process.

REFERENCES

Australian Antarctic Division, (1997), Kingston, Tasmania. Online database - (http://www.antdiv.gov.au/)

Bastesen, Steinar , (1997) (former Norwegian whaling captain, email communication)

de la Mare, William K., 1997, "Abrupt mid-twentieth-century decline in Antarctic sea-ice extent from whaling records", Nature, vol.389, pp 87-90, 4 Sept 97

Henderson-Sellers, A., 1984, "Climate Sensitivity and the Marginal Cryosphere", American Geophysical Union (Geophysical Monograph no.29, p.221-237)

Mierzejewska, A. et al. (1997), "Japanese Whaling Ship's Sea Surface Temperatures 1946-84", Bulletin of the American Meteorological Society, vol.78, No.3, March 1997

Umland, H., (1997), Personal communication and website information, http://www.online.de/home/h.umland/Default.htm