 |
| Titel |
A synthesis of the Antarctic surface mass balance during the last 800 yr |
| VerfasserIn |
M. Frezzotti, C. Scarchilli, S. Becagli, M. Proposito, S. Urbini |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1994-0416
|
| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 7, no. 1 ; Nr. 7, no. 1 (2013-02-20), S.303-319 |
| Datensatznummer |
250017421
|
| Publikation (Nr.) |
 copernicus.org/tc-7-303-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
Global climate models suggest that Antarctic snowfall should increase in a
warming climate and mitigate rises in the sea level. Several processes
affect surface mass balance (SMB), introducing large uncertainties in past,
present and future ice sheet mass balance. To provide an extended
perspective on the past SMB of Antarctica, we used 67 firn/ice core records
to reconstruct the temporal variability in the SMB over the past 800 yr
and, in greater detail, over the last 200 yr.
Our SMB reconstructions indicate that the SMB changes over most of
Antarctica are statistically negligible and that the current SMB is not
exceptionally high compared to the last 800 yr. High-accumulation periods
have occurred in the past, specifically during the 1370s and 1610s. However,
a clear increase in accumulation of more than 10% has occurred in high
SMB coastal regions and over the highest part of the East Antarctic ice
divide since the 1960s. To explain the differences in behaviour between the
coastal/ice divide sites and the rest of Antarctica, we suggest that a
higher frequency of blocking anticyclones increases the precipitation at
coastal sites, leading to the advection of moist air in the highest areas,
whereas blowing snow and/or erosion have significant negative impacts on the
SMB at windy sites. Eight hundred years of stacked records of the SMB mimic
the total solar irradiance during the 13th and 18th centuries. The
link between those two variables is probably indirect and linked to a
teleconnection in atmospheric circulation that forces complex feedback
between the tropical Pacific and Antarctica via the generation and
propagation of a large-scale atmospheric wave train. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|