By Paul Homewood
A paper published last year “Climate variability in West Greenland during the last 1500 years” by Ribeiro et al attempted to map temperature changes in Disko Bay, in West Greenland, during the last 1500 years by analysing marine sediments. Their conclusions included :-
- The past 1500 years have been identified as one of the coldest intervals of the last 7000 years in Disko Bay.
- This period is inserted in the context of the Neoglacial Advance of the Greenland Ice Sheet starting at c. 5000 years BP andculminating in the Little Ice Age(e.g. Kelly et al 1980).
- A long term cooling trend from the mid-late-holocene is consistent with air temperature reconstructions from Greenland ice core data (Vinther et al 2009,2010). ……..
- …… And with climate studies in areas influenced by the East Greenland Current (e.g. Jennings et al 2002; Moros et al 2006).
- This late Holocene cooling trend is also consistent with marine and terrestrial records from several locations in the Northern Hemisphere (e.g. Levac et al 2001; Moros et al 2004).
- The dinoflagellate cyst record Disko Bay revealed generally cold sea surface conditions and extensive sea ice throughout the entire studied period.
As well as putting the last 1500 years into long term perspective, the authors have found that their analysis confirms a warmer period between 1050 and 1250 AD and extensive sea ice conditions from 1500 AD. In particular they make this interesting comment :-
In other words, sea ice was less extensive in the MWP than now.
We therefore appear, as far as Greenland is concerned at any rate, to be going through a slightly warmer interlude within a much longer cooling period. Maybe we should be worrying that the next LIA will be colder still.