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It has been known for some time that the potential exists to construct a long daily series of surface pressure for the city of Paris because of the existence of various instrumental series that might be pieced together. The remarkable weather diary kept by the physician, Louis Morin, sets the start of the potential series to 1670, and various other series have now been digitized and corrected to allow the formation of a daily series of Mean Sea-Level Pressure (MSLP) that spans the greater part of 300 years. Unfortunately, a gap in the series still exists for the period 1726-1747, where it appears that no barometer observations have survived. This paper discusses the sources of the various pressure data used in the Paris daily MSLP series, and describes how these observations have been corrected and amalgamated to form a near-continuous, homogeneous series. The data are compared with a similar long daily series that has been independently constructed for the city of London (1692-2007). This comparison indicates that the two MSLP series are of a sufficient quality to provide useful information about the atmospheric circulation across western Europe over the last 300 years. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Two glacial deposits in the Gesso valley ( Maritime, Alps) have been 10 Be-dated at 20 140±1080 (weighted mean± SD) and 16 590±970 years, respectively, thus constraining the Last Glacial Maximum ( LGM) and Gschnitz stadials in the southwestern part of the Alps. The LGM age is chronologically coherent with MIS 2 and synchronous with most other LGM moraines in the Alps. The Gschnitz stadial also appears to be in agreement with the ages obtained from other Alpine sites and with Heinrich Event I. This suggests that the Alpine glaciers reacted simultaneously and essentially synchronously with the climate change associated with Heinrich Event 1. The Equilibrium Line Altitudes ( ELAs) of the LGM and Gschnitz reconstructed palaeoglaciers are 1850 and 1910 m a.s.l., respectively. The ELA comparison across the Alps indicates that the palaeoclimate of the Maritime Alps during the LGM was rather different from that of other Alpine sectors. However, the similar Gschnitz ELA value between the Gesso valley and other sites across the mountain chain indicates that Alpine glaciers responded with the same intensity to the climate change associated with Heinrich Event I. Overall, these results suggest that the interaction between the atmospheric circulation of air masses and local Alpine orography was more complex than has previously been argued. [ABSTRACT FROM AUTHOR]