Quantitative climate reconstruction from pollen data in the Grand Duchy of Luxembourg since 15 000 yr BP

Abstract

Cuiot, J . and Couteaux, M. 1992. Quantitative climate reconstruction from pollen data in the Grand Duchy of Luxembourg since 15 000 yr BP. /ourna/ of ABSTRACT: Monthly temperature and precipitation estimates for the period 15 000-2000 yr BP are statistically derived from pollen analytical data obtained from a site near Echternach, Luxembourg. A continuous warming trend of over 10°C is recorded for the period 10 500-8000 yr BP, along with a rise in precipitation of 500 mm. A fairly constant temperature characterised the period between 8000 and 2000 yr BP, though an episode of slight temperature decrease (-2°C) occurred at about 4500 yr BP. The most humid intervals seem to have been at around 9000-7000 and 5000-3000 yr BP (principally during the warm season: more continental influence). In contrast with results obtained from more southerly sites, the 'Older Dryas' climatic reversal is clearly recorded at Echternach slightly before 12000 yr BP. It is marked by a cooling in July temperature of about 4°C and a decrease in monthly precipitation of about 30 mm (40%). Journal of Quaternary Science

Fluvial incision and channel downcutting as a response to Late-glacial and Early Holocene climate change: the lower reach of the River Meuse (Maas), The Netherlands

“…11.3-10.9 kyr) ultimately leads to a braided system, with highest width/depth ratios during the Younger Dryas. Discontinuous permafrost is present again Figure 9 Lag time (uncalibrated 14 C years) between climatic amelioration in the upstream Ardennes area (after Guiot and Couteaux, 1992) and onset of channel downcutting in the lower reach of the Meuse River. On the y-axis, m ϩ OD stands for m above Ordnance Datum.…”

“…Walker et al (1994) andDe Graaff andDe Jong (1995) report rapid warming at the beginning of the Bølling Interstadial, gradual cooling during the Allerød and a cold phase between 11.5 and 11.3 kyr BP. Guiot and Couteaux (1992) reconstructed a marked increase in mean annual temperature and mean annual precipitation for the period 15-8 kyr BP (Fig. 9) for the Echternach area in Luxemburg (altitude 170 m).…”

“…Permafrost disappeared and a vegetation cover was established in the Pleniglacial tundra landscape due to the rapid temperature rise after 14.5 kyr BP (Guiot and Couteaux, 1992;Hoek, 1997). Decreasing gelifluction processes will have diminished the sediment supply rapidly.…”

“…The break-up of interstadial vegetation cover and soils can be expected to occur earlier in the Ardennes area than in the French and Dutch parts of the fluvial system in view of the higher (colder) altitudes, steeper slopes and presence of coarser material. The Echternach pollen diagram (Guiot and Couteaux, 1992) indicates that the Bølling birch park landscape was replaced by an Early Allerød pine woodland, which gradually declined during the Middle and Late Allerød. Pine woods were established on the Meuse lower reaches in The Netherlands during the Late Allerød, but died off rapidly during the Early Younger Dryas (Hoek, 1997).…”

“…9 we plotted bankfull channel depth versus reconstructed palaeotemperature and palaeoprecipitation for the upstream Ardennes area (Guiot and Couteaux, 1992). Bankfull channel depth has increased 500-1300 years after a major temperature (and precipitation) rise, compared with channel depths of the preceding colder period.…”