 |
| Titel |
A 10 year record of black carbon and dust from a Mera Peak ice core (Nepal): variability and potential impact on melting of Himalayan glaciers |
| VerfasserIn |
P. Ginot, M. Dumont, S. Lim, N. Patris, J.-D. Taupin, P. Wagnon, A. Gilbert, Y. Arnaud, A. Marinoni, P. Bonasoni, P. Laj |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1994-0416
|
| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 8, no. 4 ; Nr. 8, no. 4 (2014-08-14), S.1479-1496 |
| Datensatznummer |
250116262
|
| Publikation (Nr.) |
 copernicus.org/tc-8-1479-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| A shallow ice core was extracted at the summit of Mera Peak at 6376 m a.s.l.
in the southern flank of the Nepalese Himalaya range. From this core, we
reconstructed the seasonal deposition fluxes of dust and refractory black
carbon (rBC) since 1999. This archive presents well preserved seasonal
cycles based on a monsoonal precipitation pattern. According to the seasonal
precipitation regime in which 80% of annual precipitation falls between
June and September, we estimated changes in the concentrations of these
aerosols in surface snow. The analyses revealed that mass fluxes are a few
orders of magnitude higher for dust (10.4 ± 2.8 g m−2 yr−1
than for rBC (7.9 ± 2.8 mg m−2 yr−1). The relative lack of
seasonality in the dust record may reflect a high background level of dust
inputs, whether from local or regional sources. Over the 10-year record, no
deposition flux trends were detected for any of the species of interest. The
data were then used to simulate changes in the surface snow albedo over time
and the potential melting caused by these impurities. Mean potential melting
caused by dust and rBC combined was 713 kg m−2 yr−1, and for rBC
alone, 342 kg m−2 yr−1 for rBC under certain assumptions. Compared
to the melting rate measured using the mass and energy balance at
5360 m a.s.l. on Mera Glacier between November 2009 and October 2010, i.e.
3000 kg m−2 yr−1 and 3690 kg m−2 yr−1 respectively,
the impact of rBC represents less than 16% of annual potential melting
while the contribution of dust and rBC combined to surface melting
represents a maximum of 26%. Over the 10-year period, rBC variability in
the ice core signal primarily reflected variability of the monsoon signal
rather than variations in the intensity of emissions. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|