The International Panel for Climate Change (2001) reported that average global surface air temperature increased by 0.6±0.2 °C since the late 19th century and is projected to increase by 1.4–5.8 °C between 1990–2100 (approx 0.2 to 0.5 °C per decade). The response of hydrological systems, erosion processes and sedimentation in Alpine regions could therefore alter significantly due to climate change. Suspended sediment fluxes in the Glacier Noir proglacial zone in the Ecrins National Park, French Alps, have been monitored for 15-20 days in July 2003, 2004, and 2005. Discharge and turbidity were monitored at 10-min intervals and suspended sediment concentrations in 60-72 water samples collected in each season at a range of discharge values were obtained gravimetrically, and used to calibrate turbidity sensors from which suspended sediment loads were estimated. Excluding rainstorms in 2005, the common data from 11-17 July for each melt season allow us to assess the impact of the unusually warm 2003 melt season when a Europe wide heat wave prevailed for over three months. Daily mean daily air temperature at the site in 2003, 2004 and 2005 was 16.5, 10.4 and 14.0 °C; corresponding daily mean discharge was 5.5, 1.1, and 3.0 m³ sֿ¹ (or 171, 36 and 95% of the 3-year mean) and daily mean suspended sediment load was 777, 27, 343 t respectively (or 203, 7 and 90% of the 3-year mean). These data suggest that rises in temperature as predicted by current global warming models could propagate disproportionate increases in suspended sediment loads. An improved understanding of suspended sediment dynamics in proglacial zones is important since such zones are likely to expand in a warmer climate. Proglacial zones may become even more important in controlling downstream suspended sediment loads, which have important implications for the hydroelectricity industry, stream ecology, river sedimentation and channel dynamics in lowland river systems.
|Keywords:||Global Warming, Proglacial Zones, Suspended Sediment Loads|
Reader in Physical Geography & Outdoor Education, Faculty of Education, Community & Leisure, Liverpool John Moores University, Liverpool, Merseyside, UK
Lecturer, School of Geography, University of Nottingham, UK
There are currently no reviews of this product.Write a Review