 |
| Titel |
Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| VerfasserIn |
S. Arndt, M. Nicolaus |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1994-0416
|
| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 8, no. 6 ; Nr. 8, no. 6 (2014-11-28), S.2219-2233 |
| Datensatznummer |
250116385
|
| Publikation (Nr.) |
 copernicus.org/tc-8-2219-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Arctic sea ice has
not only decreased in volume during the last decades, but has also changed in
its physical properties towards a thinner and more seasonal ice cover. These
changes strongly impact the energy budget, and might affect the
ice-associated ecosystems. In this study, we quantify solar shortwave fluxes
through sea ice for the entire Arctic during all seasons. To focus on
sea-ice-related processes, we exclude fluxes through open water, scaling
linearly with sea ice concentration. We present a new parameterization of
light transmittance through sea ice for all seasons as a function of variable
sea ice properties. The maximum monthly mean solar heat flux under the ice of
30 × 105 Jm−2 occurs in June, enough heat to melt 0.3 m
of sea ice. Furthermore, our results suggest that 96% of the annual solar
heat input through sea ice occurs during only a 4-month period from May to
August. Applying the new parameterization to remote sensing and reanalysis
data from 1979 to 2011, we find an increase in transmitted light of
1.5% yr−1 for all regions. This corresponds to an increase in
potential sea ice bottom melt of 63% over the 33-year study period.
Sensitivity studies reveal that the results depend strongly on the timing of
melt onset and the correct classification of ice types. Assuming 2 weeks
earlier melt onset, the annual transmitted solar radiation to the upper ocean
increases by 20%. Continuing the observed transition from a mixed
multi-year/first-year sea ice cover to a seasonal ice cover results in an
increase in light transmittance by an additional 18%. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|