Long-term changes revealed by KRILLBASE

Currently monitoring time series in the Southern Ocean using standardised methods are of relatively short duration (< 20 years) and localised. KRILLBASE has spliced these various time series together for a larger scale and longer term view of how the ecosystem has changed. This was the idea behind a publication showing that last century that there was a decadal-scale decrease in krill abundance across the SW Atlantic sector and an increase in salp abundance in the most southerly part of their range.

This figure, from Atkinson et al. 2004 (Nature 432: 100-103) shows (a) the inter-annual variation in mean krill abundance in the SW Atlantic sector of the Southern Ocean as well as the spatial extent of these changes, both for (b) krill and (c) salps. A statistical analysis of temporal changes was done on the data-rich cells marked with a green spot. For a higher resolution version of this map click here.