Their assessment was based upon each model’s ability to simulate observed seasonal changes in ice concentrations for the period 1979-1999. For the Barents Sea, a limit of within 30% was used to determine acceptable models and those exceeding 30% were considered unacceptable. The reasoning was that the models should be able to hindcast the present day conditions if they are to do a good job on future projections. Most of the models produced too much ice in the Barents, as only 7 models met the acceptable criteria.]]>
The disappearance of seasonal sea ice will result in increased primary production in the Barents Sea (Øiestad, 1990; Loeng et al. 2005, Ellingsen et al., 2008). The disappearance of seasonal sea ice would eliminate the ice-edge blooms, which would be replaced by blooms resembling those in the more productive Atlantic waters and their timing would be determined by the onset of seasonal stratification.
Loeng et al. (2005) suggested the spring bloom would occur earlier and this would enhance annual primary production by extending the growing season. They also stated that regions where the seabed or the depth of mixing is <40 m are likely to favour diatom blooms, whereas if mixing extended to about 80 m it would likely favour Phaeocystis. Thus, projected stronger winds are likely to result in Phaeocystis becoming more common than at present in the northern and eastern regions of the Barents Sea. If the surface mixed layer extends beyond about 80 m, it is possible that a low-productive community dominated by nanoflagellates would be favoured.]]>
Re-reading of old cod-otholits suggests that age had been over estimated in the beginning of the time series in the above figure, and that the decline in age at maturity therefore has been less pronounced than suggested here (Zuykova et al 2009).]]>