A coupled model study of the last glacial maximum: Was part of the North Atlantic relatively warm?

A coupled ocean-atmosphere general circulation model is used to simulate th e climates of today and the last glacial maximum (LGM). The model, which do es not require artificial flux adjustments, produces a pattern of cooling a t the LGM that is broadly consistent with the findings from simpler models and palaeoclimatic data. However, changes to the ocean circulation produce anomalously warm LGM surface conditions over parts of the North Atlantic, s eemingly at odds with palaeoceanographic data. The thermohaline circulation is intensified for several centuries, as is the northward heat transport i n the Atlantic equatorward of 55 degreesN, but this may be a transient resu lt. Mechanisms that lead to this response are discussed.