Sentences with phrase «subpolar north»

About Blog Overturning in the Subpolar North Atlantic Program.

These findings suggest that there are two sources of low ∆ 14C waters that upwell at the Galapagos, Subantarctic Mode Water and shallow overturning water from the subpolar North Pacific.

Some scientists believe that global warming could shut down this ocean current system by creating an influx of freshwater from melting ice sheets and glaciers into the subpolar North Atlantic Ocean.

As a result, the fast and slow responses are nearly opposite to each other in spatial pattern, especially over the subpolar North Atlantic / Southern Ocean regions of the deep - water / bottom - water formation, and in the interhemispheric SST gradient between the southern and northern subtropics.

The initial weakening is mainly driven by the anomalous surface heat flux in the subpolar North Atlantic, as suggested by previous studies, while the final slow strengthening could be attributed to the reduction of brine rejection in the Southern Ocean and the subsequent weakening of Antarctic Bottom Water.

This overshoot is caused predominantly by the reduction of the meltwater in the northern North Atlantic associated with the retreat of the large amount of sea ice, an effect that becomes dominant when the subpolar North Atlantic is covered by sea ice as in the glacial condition.

Therefore, a transoceanic line in the subpolar North Atlantic, currently being planned by the international community, that measures the net contributions of the overflow waters from the Nordic Seas as well as those from the Labrador Sea, to the AMOC, would directly test the legitimacy of the decades - long supposition that variability in North Atlantic Deep Water production translates into meridional overturning variability (Figure 2.4).

The study concluded that the likely source of the heat transport anomalies was a decrease in the Agulhas Leakage and that changes in convection in the subpolar North Atlantic was an unlikely contributor to the slowdown.

Although there is very little trend in the OHC in the subpolar North Atlantic where the salinity induced vacillation cycle dominates, there is a linear OHC trend equatorward of 45 ° N and ° S in the Atlantic basin (including the Southern Ocean)(fig.

Salinity changes at subpolar North Atlantic are known to affect deep - water formation to initiate such an ocean circulation shift (25).

Salinity changes at subpolar North Atlantic are known to affect deep - water formation to initiate such an ocean circulation shift.

Strong decadal climate variability is a signature of the subpolar North Atlantic Ocean, which is also home to the global overturning circulation.

The impact of internal variability of the AMOC on the ITCZ is more uncertain, but there are interesting recent results, including high predictability of shifts in the ITCZ position (Martin and Thorncroft 2015), which seem to be related to changes in the AMOC in the subpolar North Atlantic.

A new study concludes that the likely source of changes in heat that caused the recent slowdown in the AMOC was from a decrease in the Agulhas Leakage and that changes in convection in the subpolar North Atlantic was an unlikely contributor.

Xu, X., P. B. Rhines, E. Chassignet, and W. Schmitz, 2014: Spreading of Denmark Strait overflow water in the western subpolar North Atlantic: Insights from eddy - resolving simulations with a passive tracer.

In addition to the shallow La Niña — like patterns in the Pacific that were the previous focus, we found that the slowdown is mainly caused by heat transported to deeper layers in the Atlantic and the Southern oceans, initiated by a recurrent salinity anomaly in the subpolar North Atlantic.

Fig. 3 Time series of the temperature difference between the subpolar North Atlantic and the entire northern hemisphere, which can be interpreted as an indicator of the strength of the Atlantic circulation.

But in the subpolar North Atlantic, it was the coldest on record!

The cooling in the subpolar North Atlantic is remarkable and well documented by numerous measurements — unlike the cold spot in central Africa, which on closer inspection apparently is an artifact of incomplete and inhomogeneous weather station data.

The evidence for this is the trend towards cooling in the subpolar North Atlantic which anti-correlates with temperatures in the South Atlantic (suggesting reduced heat transport from the South Atlantic to the North Atlantic).

At the same time it set a new cold record in the subpolar North Atlantic — and it was very cold in the eastern parts of North America.

Rapid switches in subpolar North Atlantic hydrography and climate during the Last Interglacial (MIS 5e).

Environmental Controls on Mg / Ca in Neogloboquadrina incompta: A Core - Top Study From the Subpolar North Atlantic.

One week ago, we published a paper in Nature Climate Change (which had been in the works for a few years) arguing that the cold in the subpolar North Atlantic is indicative of an AMOC slowdown (as discussed in my last post).

Another reason to study the AMOC in the subpolar North Atlantic is that the rugged ocean floor in this region carves the current pathways up into tortuous tributaries, unlike the relatively smooth flows at 26 ° N. OSNAP's stationary moorings can not trace these meandering pathways, so the array is supplemented by drifting floats.

«We're showing the shortcomings of climate models,» says Susan Lozier, a physical oceanographer at Duke University in Durham, North Carolina, who leads the $ 35 million, seven - nation project known as the Overturning in the Subpolar North Atlantic Program (OSNAP).

Last week, at the American Geophysical Union's Ocean Sciences meeting here, scientists presented the first data from an array of instruments moored in the subpolar North Atlantic.

«Warm summers could weaken ocean circulation: Long - term observations reveal the influence of increased surface freshening on convection in the subpolar North Atlantic.»

Not exact matches

Unfortunately, North Atlantic polar and subpolar waters that now offer hospitable refuge down to depths of 3 km will become mostly corrosive by the end of the century due to invasion of fossil fuel CO2.

In the North Atlantic, the measured values differ markedly from the average global warming: the subpolar Atlantic (an area about half the size of the USA, south of Greenland) has hardly warmed up and in some cases even cooled down, contrary to the global warming trend.

Model simulations for the North Atlantic Ocean and thermodynamic principles reveal that this feedback should be stronger, at present, in colder midlatitude and subpolar waters because of the lower present - day buffer capacity and elevated DIC levels driven either by northward advected surface water and / or excess local air - sea CO2 uptake.

North Atlantic subpolar gyre along predetermined ship tracks since 1993: a monthly dataset of surface temperature, salinity, and density

1) It appears AGW that melts arctic freshwater also results in a negative feedback that acts against runaway warming; more warm Gulf Stream volume eventually results in less cool volume from Antarctic subpolar current to North equatorial at the base of Cuba.

The sea surface temperature (SST) anomalies that define the AMV are characterized by a basin - scale pattern that has the same sign over the whole North Atlantic, with a maximum loading over the subpolar gyre region.

The strength of the Icelandic Low is the critical factor in determining path of the polar jet stream over the North Atlantic In the winter the IL is located at SW of Greenland (driver Subpolar Gyre), but in the summer the IL is to be found much further north (most likely driver the North Icelandic Jet, formed by complex physical interactions between warm and cold currents), which as graphs show had no major ups or dNorth Atlantic In the winter the IL is located at SW of Greenland (driver Subpolar Gyre), but in the summer the IL is to be found much further north (most likely driver the North Icelandic Jet, formed by complex physical interactions between warm and cold currents), which as graphs show had no major ups or dnorth (most likely driver the North Icelandic Jet, formed by complex physical interactions between warm and cold currents), which as graphs show had no major ups or dNorth Icelandic Jet, formed by complex physical interactions between warm and cold currents), which as graphs show had no major ups or downs.

The strength of the Icelandic Low is the critical factor in determining path of the polar jet stream over the North Atlantic In the winter the IL is located at SW of Greenland (Subpolar Gyre) In summer the IL is to be found much further north (most likely the North Icelandic Jet, formed by complex physical interactions between warm and cold currents) These two run under two different regimes and two clocks (see the CET synthesis from 3 harmonics, one for each summer and winter, and one common — see the above link, bottom grNorth Atlantic In the winter the IL is located at SW of Greenland (Subpolar Gyre) In summer the IL is to be found much further north (most likely the North Icelandic Jet, formed by complex physical interactions between warm and cold currents) These two run under two different regimes and two clocks (see the CET synthesis from 3 harmonics, one for each summer and winter, and one common — see the above link, bottom grnorth (most likely the North Icelandic Jet, formed by complex physical interactions between warm and cold currents) These two run under two different regimes and two clocks (see the CET synthesis from 3 harmonics, one for each summer and winter, and one common — see the above link, bottom grNorth Icelandic Jet, formed by complex physical interactions between warm and cold currents) These two run under two different regimes and two clocks (see the CET synthesis from 3 harmonics, one for each summer and winter, and one common — see the above link, bottom graph).

Not only has the AMOC slowed down (Cunningham et al [2013]-RRB-, but sea surface temperatures in North Atlantic subpolar gyre have begun falling, as have sea surface temperatures in the North Pacific subtropical gyre - best illustrated by the Pacific Decadal Oscillation (PDO) being strongly positive this year.

not entirely clear, but since it is the north leg of the NAO (Icelandic pressure) that is determinant, it presumably takes some years for the warm atlantic currents to reach the Arctic and return as cold currents via Denmark Strait (Icelandic pressure) and few more years to loop into the subpolar gyre to initiate AMO oscillation Hence in order of occurrence NAP > NAO > AMO (refer to http://www.vukcevic.talktalk.net/NAOn.htm one but last illustration) Just as a reminder compare NAP waveform with the CET spectrum components (1660 - 2021) http://www.vukcevic.talktalk.net/CET-NV.htm I hope some of the above helps, but if not than your «how you cook up your «secret recipe» NAP misgiving is by far safer than accepting «blanco» assurance.

The Pacific SST modes are further related to atmospheric forcing, and the circulation of the North Pacific subpolar and subtropical gyres.

Bauch, H. A., Kandiano, E. S. & Helmke, J. P. Contrasting ocean changes between the subpolar and polar North Atlantic during the past 135 ka.

This in turn is influenced by sea level pressure patterns in polar and subpolar regions — as more or less wind and currents are pushed north (Roemmich et al, 2007, Qiu, Bo et al 2006).

A faster AMOC tends to transport more saline water to the North Atlantic subpolar region, where it loses some heat to the cold atmosphere and sinks.

FIGURE 2.1 Schematic of the major warm (red to yellow) and cold (blue to purple) water pathways in the North Atlantic subpolar gyre.

In the North Atlantic, away from the subpolar regions, the MOC (which is in principle an observable quantity) is often identified with the Thermohaline Circulation (THC), which is a conceptual interpretation.

If sustained, these winds strengthen the subpolar gyre that circles counterclockwise in the far North Atlantic.

Glaciers involved in mass balance studies are sparsely distributed over all mountain and subpolar regions, with about 70 percent of the observations coming from the mountains of Europe, North America, and the former Soviet Union.