Sentences with phrase «reduced sea ice concentration»

Nørgaard - Pedersen, N., Mikkelsen, N., Lassen, S. J., Kristoffersen, Y. & Sheldon, E. Reduced sea ice concentrations in the Arctic Ocean during the last interglacial period revealed by sediment cores off northern Greenland.

Not exact matches

The research team — which utilized 34,000 data records from 2010 and 2011 — concluded that melting sea ice is diluting seawater and reducing the concentrations of the carbonate minerals critical as building blocks for the shells of marine life.

This suggests that atmospheric carbon dioxide concentrations of 400 ppm may be sufficient to greatly reduce the spatial extent and seasonal persistence of Arctic sea ice.

If Arctic sea ice is reduced, we may therefore be facing an increase of atmospheric concentration of CO2, researchers warn.

Because walrus avoid ice - covered waters where sea ice concentration is 80 % or greater, any heavy ice concentrations reduce the areal extent of walrus foraging habitat.

Improvements were made to the statistical method, including the use of high resolution AMSR - E sea ice concentration data, a time - domain filter of five days that reduces observational noise, and a space - domain selection that neglects the outer seasonal ice zones.

We introduced following improvements: high resolution (AMSR - E) sea ice concentration data, a time - domain filter that reduces observational noise, and a space - domain selection that neglects the outer seasonal ice zones.

Whereas most proxy - based reconstructions point to an early - middle LIG climatic optimum with reduced summer sea ice concentrations between 126 and 116 ka, the results of our model simulations only support a pronounced reduction in summer sea ice concentration for the LIG - 125 and LIG - 130 runs (in both time slice as well as transient runs; Figs. 8 and 9), but also indicate that sea ice was still present in the central Arctic Ocean even under climatic conditions significantly warmer than today (Fig. 4).

Additionally, we show results from a sensitivity study with a reduced Greenland Ice Sheet (GrIS) at 130 ka28 and for a 130 ka scenario with a closed Bering Strait (BS) and half - flooded Siberian shelf seas (Supplementary Fig. 9) as well as for future (2300 and 2100) scenarios following the IPCC Representative Concentration Pathway (RCP) scenarios RCP4.5 (583 ppm CO2eq) and RCP6 (808 ppm CO2eq) 2, 27.

Higher methane concentrations in the atmosphere will accelerate global warming and hasten local changes in the Arctic, speeding up sea - ice retreat, reducing the reflection of solar energy and accelerating the melting of the Greenland ice sheet.

Multi-year sea ice has been reduced to such low levels that the overall September sea ice extent is largely tied to the fate of the first - year sea ice, which appears thin or with low concentrations away from the central Arctic (see AMSR satellite data and the calculations by Lindsay and Rigor).

Taken together, the average of the warmest times during the middle Pliocene presents a view of the equilibrium state of a globally warmer world, in which atmospheric CO2 concentrations (estimated to be between 360 to 400 ppm) were likely higher than pre-industrial values (Raymo and Rau, 1992; Raymo et al., 1996), and in which geologic evidence and isotopes agree that sea level was at least 15 to 25 m above modern levels (Dowsett and Cronin, 1990; Shackleton et al., 1995), with correspondingly reduced ice sheets and lower continental aridity (Guo et al., 2004).

A combined lack of coherence in ice drift fields and reduced ice concentrations in April 2011 relative to April 2007 suggest that springtime ice dynamical contributions to fall sea ice extent may be associated with sea ice deformation and ridging within an increasingly mobile and fractured ice cover.