 |
| Titel |
Summer cloud and precipitation properties at Utsteinen, Dronning Maud Land, Antarctica, measured by ground-based remote sensing instruments |
| VerfasserIn |
I. V. Gorodetskaya, N. P. M. van Lipzig, S. Kneifel, M. Maahn, S. Crewell, M. van den Broeke |
| Konferenz |
EGU General Assembly 2012
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250066788
|
|
|
|
|
|
| Zusammenfassung |
| A unique comprehensive observatory on meteorological-cloud-precipitation interactions has
been built at the new Belgian Princess Elisabeth station, situated on the Utsteinen ridge, at the
foot of Sør Rondane mountains in East Antarctica (http://ees.kuleuven.be/hydrant).
The instruments already installed include an automatic weather station (AWS) and
three ground-based cloud and precipitation remote sensing instruments (ceilometer,
infra-red pyrometer and 24GHz vertically pointing radar). The cloud and precipitation
instruments have been operating during three summer periods (2009-2010, 2010-2011 and
2011-2012), while the AWS has been operating almost continuously since February 2009
through present time. The measurements are combined in order to obtain basic
statistics of clouds properties (height and cloud base temperature), their radiative
forcing, as well as frequency and vertical extension of snowfall events, together
with the meteorological situation at Utsteinen. Measurements during the first two
summer campaigns showed that cloud base temperatures ranged between -200C for
low-level clouds (1-1.5 km agl) and -350C - -400C for midlevel clouds (2-4 km agl).
The 1-3 km height range was found to have the highest cloud frequency. Synoptic
events with and without snowfall have been related to the water vapor transport and
local cloud properties. One of the analyzed storms with snowfall in February 2010
showed a two-day evolution with low-level and mid-level clouds observed during
the first day, forming multiple layers with short periods of light precipitation, and
lowering cloud bases during the second day followed by snowfall and blowing snow.
Increase in the cloud base temperature associated both with warm air advection and
cloud base lowering (to 1-1.5 km agl) before the snowfall resulted in significant
increase in downwelling longwave flux (up to 20 W m-2) recorded by the AWS
pyrgeometer. While ceilometer measurements are limited during the storm due to the signal
attenuation by the falling and/or blowing snow, the radar measurements indicated that the
depth of precipitating layer ranged from 1 km to at least 3 km agl (the limit of the
radar vertical resolution). Analysis will be completed with the new data from the
recent Antarctic summer season 2011-2012. With this new observatory, we aim at
improving our understanding of the Antarctic hydrologic cycle and accumulation |
|
|
|
|
|
|