Publication Date:
2021-01-27
Description:
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.
Description:
Published
Description:
303–319
Description:
3.8. Geofisica per l'ambiente
Description:
JCR Journal
Description:
open
Keywords:
Antarctica
;
Surface Mass Balance
;
Global Climate Models
;
Ice core
;
02. Cryosphere::02.02. Glaciers::02.02.02. Cryosphere/atmosphere Interaction
;
02. Cryosphere::02.02. Glaciers::02.02.06. Mass balance
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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