scholarly journals Climate change impacts on sea-air fluxes of CO<sub>2</sub> in three Arctic seas: a sensitivity study using earth observation

2012 ◽  
Vol 9 (9) ◽  
pp. 12377-12432 ◽  
Author(s):  
P. E. Land ◽  
J. D. Shutler ◽  
R. D. Cowling ◽  
D. K. Woolf ◽  
P. Walker ◽  
...  

Abstract. During 2008 and 2009 we applied coincident Earth observation data collected from multiple sensors (RA2, AATSR and MERIS, mounted on the European Space Agency satellite Envisat) to characterise environmental conditions and net sea-air fluxes of CO2 in three Arctic seas (Greenland, Barents, Kara) to assess net CO2 sink sensitivity due to changes in temperature, salinity and sea ice duration arising from future climate scenarios. During the study period the Greenland and Barents Seas were net sinks for atmospheric CO2, with sea-air fluxes of −34±13 and −13±6 Tg C yr−1, respectively and the Kara Sea was a weak net CO2 source with a sea-air flux of +1.5±1.1 Tg C yr−1. The combined net CO2 sea-air flux from all three was −45±18 Tg C yr−1. In a sensitivity analysis we varied temperature, salinity and sea ice duration. Variations in temperature and salinity led to modification of the transfer velocity, solubility and partial pressure of CO2 taking into account the resultant variations in alkalinity and dissolved organic carbon (DOC). Our results showed that warming had a strong positive effect on the annual net sea-air flux of CO2 (i.e. reducing the sink), freshening had a strong negative effect and reduced sea ice duration had a small but measurable positive effect. In the climate change scenario examined, the effects of warming in just over a decade of climate change up to 2020 outweighed the combined effects of freshening and reduced sea ice duration. Collectively these effects gave a net sea-air flux change of +3.5 Tg C in the Greenland Sea, +5.5 Tg C in the Barents Sea and +1.4 Tg C in the Kara Sea, reducing the Greenland and Barents sinks by 10% and 50% respectively, and increasing the weak Kara Sea source by 64%. Overall, the regional flux changed by +10.4 Tg C, reducing the regional sink by 23%. In terms of CO2 sink strength we conclude that the Barents Sea is the most susceptible of the three regions to the climate changes examined. Our results imply that the region will cease to be a net CO2 sink by 2060.

2013 ◽  
Vol 10 (12) ◽  
pp. 8109-8128 ◽  
Author(s):  
P. E. Land ◽  
J. D. Shutler ◽  
R. D. Cowling ◽  
D. K. Woolf ◽  
P. Walker ◽  
...  

Abstract. We applied coincident Earth observation data collected during 2008 and 2009 from multiple sensors (RA2, AATSR and MERIS, mounted on the European Space Agency satellite Envisat) to characterise environmental conditions and integrated sea–air fluxes of CO2 in three Arctic seas (Greenland, Barents, Kara). We assessed net CO2 sink sensitivity due to changes in temperature, salinity and sea ice duration arising from future climate scenarios. During the study period the Greenland and Barents seas were net sinks for atmospheric CO2, with integrated sea–air fluxes of −36 ± 14 and −11 ± 5 Tg C yr−1, respectively, and the Kara Sea was a weak net CO2 source with an integrated sea–air flux of +2.2 ± 1.4 Tg C yr−1. The combined integrated CO2 sea–air flux from all three was −45 ± 18 Tg C yr−1. In a sensitivity analysis we varied temperature, salinity and sea ice duration. Variations in temperature and salinity led to modification of the transfer velocity, solubility and partial pressure of CO2 taking into account the resultant variations in alkalinity and dissolved organic carbon (DOC). Our results showed that warming had a strong positive effect on the annual integrated sea–air flux of CO2 (i.e. reducing the sink), freshening had a strong negative effect and reduced sea ice duration had a small but measurable positive effect. In the climate change scenario examined, the effects of warming in just over a decade of climate change up to 2020 outweighed the combined effects of freshening and reduced sea ice duration. Collectively these effects gave an integrated sea–air flux change of +4.0 Tg C in the Greenland Sea, +6.0 Tg C in the Barents Sea and +1.7 Tg C in the Kara Sea, reducing the Greenland and Barents sinks by 11% and 53%, respectively, and increasing the weak Kara Sea source by 81%. Overall, the regional integrated flux changed by +11.7 Tg C, which is a 26% reduction in the regional sink. In terms of CO2 sink strength, we conclude that the Barents Sea is the most susceptible of the three regions to the climate changes examined. Our results imply that the region will cease to be a net CO2 sink in the 2050s.


2021 ◽  
Author(s):  
YiBo Du ◽  
Jie Zhang ◽  
Siwen Zhao ◽  
Zhiheng Chen

Abstract The frequency of extreme drought events in northeastern China (NEC) has increased since the 2000s, and such a decadal anomalous trend may lead to significant stress on agriculture and economic development. The correlation between Arctic sea ice loss in spring and extreme summer droughts over NEC was investigated. The results show that the loss of sea ice over the Barents Sea in spring is associated with extreme droughts and positive height anomalies over NEC in summer. The physical processes include two pathways. First, Arctic ice loss from the Barents Sea to the Kara Sea results in reducing baroclinicity over the ice loss region but increasing baroclinicity over the ice melting region, which is favorable to the wave ridge over northern Europe and negative-phase Summer North Atlantic Oscillation (SNAO). One wave train originates from negative-phase SNAO over North Atlantic–Europe and spreads to central Europe, central Asia, and NEC. Second, another wave motion flux originates from the Barents–Kara Sea propagating eastward, and then disperses southward to NEC. Both wave trains lead to anomalous anticyclonic circulation and westward subtropical high, which favors descending motion and less water vapor flux, thereby contributing to extreme drought.


Author(s):  
Jianfei Liu ◽  
Guoqing Feng ◽  
Huilong Ren ◽  
Wenjia Hu ◽  
Yuwei Sun

Abstract Ships performing their missions in the polar regions will inevitably suffer from sea ice collision, which will lead to structural safety problems. Therefore, ships should be designed according to the characteristics of polar sea ice to enable them to navigate safely in the polar regions. Based on the probability density curve of sea ice thickness and the occurrence frequency of sea ices of different sizes of the Kara Sea and the Barents Sea, this paper preliminarily designs ship’s bow sailing in the Kara Sea and the Barents Sea, establishes the ship’s bow-ice collision model and carries out numerical simulation to obtain the stress distribution. Then it optimizes the structure of the parts of the ship’s bow. After the optimization, the bow structure meets the strength requirements and the weight of the ship’s bow is relatively light.


2018 ◽  
Author(s):  
Ira Leifer ◽  
F. Robert Chen ◽  
Thomas McClimans ◽  
Frank Muller Karger ◽  
Leonid Yurganov

Abstract. Over a decade (2003–2015) of satellite data of sea-ice extent, sea surface temperature (SST), and methane (CH4) concentrations in lower troposphere over 10 focus areas within the Barents and Kara Seas (BKS) were analyzed for anomalies and trends relative to the Barents Sea. Large positive CH4 anomalies were discovered around Franz Josef Land (FJL) and offshore west Novaya Zemlya in early fall. Far smaller CH4 enhancement was found around Svalbard, downstream and north of known seabed seepage. SST increased in all focus areas at rates from 0.0018 to 0.15 °C yr−1, CH4 growth spanned 3.06 to 3.49 ppb yr−1. The strongest SST increase was observed each year in the southeast Barents Sea in June due to strengthening of the warm Murman Current (MC), and in the south Kara Sea in September. The southeast Barents Sea, the south Kara Sea and coastal areas around FJL exhibited the strongest CH4 growth over the observation period. Likely sources are CH4 seepage from subsea permafrost and hydrate thawing and the petroleum reservoirs underlying the central and east Barents Sea and the Kara Sea. The spatial pattern was poorly related to seabed depth. However, the increase in CH4 emissions over time may be explained by a process of shoaling of strengthening warm ocean currents that would also advect the CH4 to areas where seasonal deepening of the surface ocean mixed layer depth leads to ventilation of these water masses. Continued strengthening of the MC will further increase heat transfer to the BKS, with the Barents Sea ice-free in ~ 15 years. We thus expect marine CH4 flux to the atmosphere from this region to continue increasing.


Author(s):  
Nataliya Marchenko

The 5 Russian Arctic Seas have common features, but differ significantly from each other in the sea ice regime and navigation specifics. Navigation in the Arctic is a big challenge, especially during the winter season. However, it is necessary, due to limited natural resources elsewhere on Earth that may be easier for exploitation. Therefore sea ice is an important issue for future development. We foresee that the Arctic may become ice free in summer as a result of global warming and even light yachts will be able to pass through the Eastern Passage. There have been several such examples in the last years. But sea ice is an inherent feature of Arctic Seas in winter, it is permanently immanent for the Central Arctic Basin. That is why it is important to get appropriate knowledge about sea ice properties and operations in ice conditions. Four seas, the Kara, Laptev, East Siberian, and Chukchi have been examined in the book “Russian Arctic Seas. Navigation Condition and Accidents”, Marchenko, 2012 [1]. The book is devoted to the eastern sector of the Arctic, with a description of the seas and accidents caused by heavy ice conditions. The traditional physical-geographical characteristics, information about the navigation conditions and the main sea routes and reports on accidents that occurred in the 20th century have reviewed. An additional investigation has been performed for more recent accidents and for the Barents Sea. Considerable attention has been paid to problems associated with sea ice caused by the present development of the Arctic. Sea ice can significantly affect shipping, drilling, and the construction and operation of platforms and handling terminals. Sea ice is present in the main part of the east Arctic Sea most of the year. The Barents Sea, which is strongly influenced and warmed by the North Atlantic Current, has a natural environment that is dramatically different from those of the other Arctic seas. The main difficulties with the Barents Sea are produced by icing and storms and in the north icebergs. The ice jet is the most dangerous phenomenon in the main straits along the Northern Sea Route and in Chukchi Seas. The accidents in the Arctic Sea have been classified, described and connected with weather and ice conditions. Behaviour of the crew is taken into consideration. The following types of the ice-induced accidents are distinguished: forced drift, forced overwintering, shipwreck, and serious damage to the hull in which the crew, sometimes with the help of other crews, could still save the ship. The main reasons for shipwrecks and damages are hits of ice floes (often in rather calm ice conditions), ice nipping (compression) and drift. Such investigation is important for safety in the Arctic.


Polar Record ◽  
1995 ◽  
Vol 31 (177) ◽  
pp. 129-134 ◽  
Author(s):  
Gennady I. Belchansky ◽  
Ilia N. Mordvintsev ◽  
Gregory K. Ovchinnikov ◽  
David C. Douglas

AbstractTrends in the annual minimum sea-ice extent, determined by three criteria (absolute annual minimum, minimum monthly mean, and the extent at the end of August), were investigated for the Barents and western Kara seas and adjacent parts of the Arctic Ocean during 1984–1993. Four definitions of ice extent were examined, based on thresholds of ice concentration: >90%, >70%, >40%, and >10% (El, E2, E3, and E4, respectively). Trends were studied using ice maps produced by the Russian Hydro-Meteorological Service, Kosmos and Okean satellite imagery, and data extracted from published literature. During 1984–1993, an increasing trend in the extent of minimum sea-ice cover was observed in the Barents, Kara, and combined Barents–Kara seas, for all ice-extent definitions. Root-mean-square differences between hydro-meteorological ice maps and satellite-image ice classifications for coincident areas and dates were 15.5%, 19.3%, 18.8%, and 11.5%, for ice extensions El–E4, respectively. The differences were subjected to Monte Carlo analyses to construct confidence intervals for the 10-year ice-map trends. With probability p = 0.8, the average 10-year increase in the minimum monthly mean sea-ice extent (followed in brackets by the average increase in the absolute annual minimum ice extent) was 12–46% [26–96%], 31–71% [55–140%], 30–69% [26–94%], and 48–94% [35–108%] in the Barents Sea; 20–60% [32–120%], 10–45% [20–92%], 2–36% [13–78%], and 10–47% [8–69%] in the Kara Sea; and 9–43% [26–59%], 9–41% [30–63%], 8–41% [22–52%] and 15–51% [21–51%] in the combined Barents–Kara seas, for ice concentrations El–E4, respectively. Including published data from 1966–1983, the trend in minimum monthly mean sea-ice extent for the combined 28-year period showed an average reduction of 8% in the Barents Sea and a 55% reduction in the western Kara Sea; ice extent at the end of August showed an average reduction of 33% in the Barents Sea.


2021 ◽  
Author(s):  
Hannah Zanowski ◽  
Alexandra Jahn ◽  
Marika Holland

&lt;p&gt;Recently, the Arctic has undergone substantial changes in sea ice cover and the hydrologic cycle, both of which strongly impact the freshwater storage in, and export from, the Arctic Ocean. Here we analyze Arctic freshwater storage and fluxes in 7 climate models from the Coupled Model Intercomparison Project phase 6 (CMIP6) and assess their agreement over the historical period (1980-2000) and in two future emissions scenarios, SSP1-2.6 and SSP5-8.5. In the historical simulation, few models agree closely with observations over 1980-2000. In both future scenarios the models show an increase in liquid (ocean) freshwater storage in conjunction with a reduction in solid storage and fluxes through the major Arctic gateways (Bering Strait, Fram Strait, Davis Strait, and the Barents Sea Opening) that is typically larger for SSP5-8.5 than SSP1-2.6. The liquid fluxes through the gateways exhibit a more complex pattern, with models exhibiting a change in sign of the freshwater flux through the Barents Sea Opening and little change in the flux through the Bering Strait in addition to increased export from the remaining straits by the end of the 21st century. A decomposition of the liquid fluxes into their salinity and volume contributions shows that the Barents Sea flux changes are driven by salinity changes, while the Bering Strait flux changes are driven by compensating salinity and volume changes. In the straits west of Greenland (Nares, Barrow, and Davis straits), the models disagree on whether there will be a decrease, increase, or steady liquid freshwater export in the early to mid 21st century, although they mostly show increased liquid freshwater export in the late 21st century. The underlying cause of this is a difference in the magnitude and timing of a simulated decrease in the volume flux through these straits. Although the models broadly agree on the sign of late 21st century storage and flux changes, substantial differences exist between the magnitude of these changes and the models&amp;#8217; Arctic mean states, which shows no fundamental improvement in the models compared to CMIP5.&lt;/p&gt;


2017 ◽  
Vol 30 (22) ◽  
pp. 8913-8927 ◽  
Author(s):  
Svenja H. E. Kohnemann ◽  
Günther Heinemann ◽  
David H. Bromwich ◽  
Oliver Gutjahr

The regional climate model COSMO in Climate Limited-Area Mode (COSMO-CLM or CCLM) is used with a high resolution of 15 km for the entire Arctic for all winters 2002/03–2014/15. The simulations show a high spatial and temporal variability of the recent 2-m air temperature increase in the Arctic. The maximum warming occurs north of Novaya Zemlya in the Kara Sea and Barents Sea between March 2003 and 2012 and is responsible for up to a 20°C increase. Land-based observations confirm the increase but do not cover the maximum regions that are located over the ocean and sea ice. Also, the 30-km version of the Arctic System Reanalysis (ASR) is used to verify the CCLM for the overlapping time period 2002/03–2011/12. The differences between CCLM and ASR 2-m air temperatures vary slightly within 1°C for the ocean and sea ice area. Thus, ASR captures the extreme warming as well. The monthly 2-m air temperatures of observations and ERA-Interim data show a large variability for the winters 1979–2016. Nevertheless, the air temperature rise since the beginning of the twenty-first century is up to 8 times higher than in the decades before. The sea ice decrease is identified as the likely reason for the warming. The vertical temperature profiles show that the warming has a maximum near the surface, but a 0.5°C yr−1 increase is found up to 2 km. CCLM, ASR, and also the coarser resolved ERA-Interim data show that February and March are the months with the highest 2-m air temperature increases, averaged over the ocean and sea ice area north of 70°N; for CCLM the warming amounts to an average of almost 5°C for 2002/03–2011/12.


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