Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice
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 sh...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2014-11-01
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| Series: | The Cryosphere |
| Online Access: | http://www.the-cryosphere.net/8/2219/2014/tc-8-2219-2014.pdf |
| _version_ | 1811331140162682880 |
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| author | S. Arndt M. Nicolaus |
| author_facet | S. Arndt M. Nicolaus |
| author_sort | S. Arndt |
| collection | DOAJ |
| description | 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 × 10<sup>5</sup> Jm<sup>−2</sup> 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<sup>−1</sup> 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%. |
| first_indexed | 2024-04-13T16:14:43Z |
| format | Article |
| id | doaj.art-1e1b47d4062f459ba865329f14e2f6e5 |
| institution | Directory Open Access Journal |
| issn | 1994-0416 1994-0424 |
| language | English |
| last_indexed | 2024-04-13T16:14:43Z |
| publishDate | 2014-11-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | The Cryosphere |
| spelling | doaj.art-1e1b47d4062f459ba865329f14e2f6e52022-12-22T02:40:05ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242014-11-01862219223310.5194/tc-8-2219-2014Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea iceS. Arndt0M. Nicolaus1Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Bussestraße 24, 27570 Bremerhaven, GermanyAlfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Bussestraße 24, 27570 Bremerhaven, GermanyArctic 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 × 10<sup>5</sup> Jm<sup>−2</sup> 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<sup>−1</sup> 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%.http://www.the-cryosphere.net/8/2219/2014/tc-8-2219-2014.pdf |
| spellingShingle | S. Arndt M. Nicolaus Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice The Cryosphere |
| title | Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| title_full | Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| title_fullStr | Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| title_full_unstemmed | Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| title_short | Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice |
| title_sort | seasonal cycle and long term trend of solar energy fluxes through arctic sea ice |
| url | http://www.the-cryosphere.net/8/2219/2014/tc-8-2219-2014.pdf |
| work_keys_str_mv | AT sarndt seasonalcycleandlongtermtrendofsolarenergyfluxesthrougharcticseaice AT mnicolaus seasonalcycleandlongtermtrendofsolarenergyfluxesthrougharcticseaice |