0000000000683923
AUTHOR
David Williamson
showing 3 related works from this author
Montagnes d'Afrique Tropicale : marqueurs de la variabilité climatique ou isolats climatiques ?
2011
International audience; Tropical mountains are often seen as beacons of past and present-day climate change. However, do they actually reflect interannual and decadal-scale climatic variability of the surrounding areas ? At the scale of Africa South of the Sahara, an analysis of the 1941-2000 rainfall variability shows that spatial coherence is seldom modified by relief. Examples are presented in which mountain climates are even indicators of large-scale atmospheric dynamics and climate variability.
Macrofossil evidence of Late Holocene presence of Aldrovanda vesiculosa L. in Central-Eastern Europe (Poland) and East Africa (Tanzania)
2015
International audience; To date, the seeds of waterwheel plant (Aldrovanda vesiculosa) were only found in Europe, in sediments of the Eemian and Mazovian Interglacials. The absence of A. vesiculosa seeds in European Holocene deposits is probably due to unfavorable climatic conditions, i.e. lower temperature, during this period: in temperate zones, A. vesiculosa reproduces mainly in a vegetative way; it rarely blooms and only occasionally produces seeds. In this paper, subfossil seeds of A. vesiculosa were identified in two peat bogs: one (Sucha Kobyła) in SE Poland and another one (Kyambangunguru) in SW Tanzania. Single seeds of this plant were found in a peat layer from the Polish site for…
Montagnes d’Afrique tropicale : marqueurs de la variabilité climatique ou isolats climatiques ?
2011
6 pages; International audience; Les montagnes tropicales sont souvent perçues comme des sentinelles des changements climatiques. Pour autantles variations climatiques interannuelles à décennales sont-elles le reflet de celles des espaces environnants ? A l’échelle del’Afrique au sud du Sahara, une analyse de la variabilité des pluies entre 1941 et 2000 montre une cohérence spatiale peudiminuée par les reliefs. Des exemples sont présentés de reliefs constituant même des révélateurs de la dynamiqueatmosphérique et de la variabilité climatique d’échelles larges.