No es que se pare la corriente, es lo que lo esta causando y es el Oceano Artico el que esta causando que toda la enorme cadena de circulación termohalina se desmorone, y cuando digo toda estoy tambien hablando de la muy posible parada de la corriente del pacifico norte aunque en este comunicado no se mencione la corriente del pacifico.
Conception of the joint AARI/NPI Laboratory
Summary
The overall direction of the Fram Arctic Laboratory (FAL) is to carry out joint
Norwegian-Russian research on Arctic climate change. Thematically the
focus is on studies of long-term changes in the physical system
including the marine system (ocean and sea ice), the atmosphere and
the terrestrial system (glaciers and fresh water). Geographically the focus is
on the Euro-Arctic region, with special emphasis on Svalbard and the
Greenland- and Barents Seas. The collaboration will include joint research
programmes implemented in Barentsburg, Ny-Alesund and Longyearbyen.
Introduction
The Arctic environment has undergone significant temperature swings over
the last 100 years. Over the last 30 years trends show surface temperature
warming, melting permafrost, reduced sea-ice, longer growing seasons and
changes in the character of ocean fluxes. It is important to recognize that
these events have already occurred or are under way, and that it is
desirable to anticipate their future course or at least assess their potential
range. Largely because global warming simulations suggest an amplified
climate response in the Arctic, it has been argued that Arctic climate provides
an early warming of global change. It has also been pointed out, however,
that climate variability in the Arctic is large, so that a weak ignal-to-noise ratio
may
initially mask climate trends. It seems likely that both the amplified climate
response and the large natural variability are connected with the strong
feedbacks that characterize the Arctic climate system. The long-term climate
data series and Arctic expertise available in Norway and Russia represent
a unique platform for obtaining scientific achievements in Arctic climate
change research. The FAL is an appropriate instrument for reaching such
goals. In the following, scientific directions of the FAL are shortly presented.
In the appendices, specific project ideas that have been identified jointly
between the Arctic and Antarctic Research Institute (AARI) and the Norwegian
Polar Institute (NPI) are described.
Sea ice
Sea ice has a dramatic effect on the physical characteristics of the ocean surface.
It modifies the surface radiation balance due to its high albedo, and it influences
the exchange of momentum, heat, and matter between atmosphere and ocean.
It also results in much lower surface air temperatures over the ice-covered areas
in winter than are maintained by the ocean immediately underneath. Freezing of
sea ice expels brine which deepens the surface mixed layer and can, through
convection, influence the formation of deep and bottom water. Melting, in
contrast, produces relatively fresh water that stratifies the oceanic surface
layers (i.e. the mixed layer retreats to shallower depths). In contrast to low
latitudes, the mixed layer evolution in Polar Regions is dominated by surface
fluxes of salt or fresh water (positive or negative freezing rates). Through these
effects, sea ice plays a key role in the global heat balance and the global
thermohaline circulation.
A retreat of sea ice associated with climate warming can therefore have global
consequences and contributes, through various feedback processes, to
enhanced climate change, particularly at high latitudes. In the FAL collaboration
we wish to focus on a wide variety of studies connected to sea ice and climate,
in particular variability and trends of sea ice concentration, sea ice thickness, and
sea ice fluxes (in the Fram Strait) as well as physical and optical properties of sea
ice. Special emphasis on sea ice-albedo feedback mechanisms will be given
Physical oceanography
The past decade has seen remarkable changes in the marine Artic, including
changes in the distribution of Atlantic source waters and the subsurface
temperature. The exchange through the Fram Strait is of special importance in
this context. In particular, the West Spitsbergen Current has been shown to cause
large changes in the Atlantic layer of the Arctic Ocean. This West Spitsbergen
Current temperature variabilityhas in turn been related to major changes in the
atmospheric circulation via the Arctic Oscillation and/or the North Atlantic
Oscillation. The FAL will utilise long-term hydrographical data from the
Greenland- and Barents Seas to study variability and trends of ocean fluxes
including changes in transport of heat and salt. Additionally, emphasis will be
made on studies of long-term variability of sea level in the Arctic Ocean.
Atmosphere
The proximity of open water in the Norwegian Arctic has potentially large effects
on the cloud-radiative interactions that determine surface climate and, potentially,
climate change over a substantial portion of the Northern Hemisphere. Climate
models must accurately simulate radiative controls of the ice-albedo-temperature
feedback if simulations by these models are to be realistic. In addition, the use of
remote sensing techniques in this region is complicated by surface melt during
warm-air intrusions, by thick clouds that accompany winter storms, and by the
complex interactions involving aerosols and clouds.Consequently, remote-sensing
algorithms developed for otherregions of the Arctic may need important modifications
when applied to this "warm Arctic"region. For ground truth measurements, there exist
excellent ground facilities both in Barentsburg and Ny-Alesund. In addition, both
these research stations maintain long-termmeteorological data series. In FAL
comparative studies between Barentsburg and Ny-Alesund with respect to solar
radiation should be attempted. Further, it is recommended that satellite-based studies
of surface albedo should be made.
Glaciology and hydrology
Svalbard is located at the climate boundary of the polar front. Any shift in the position
of thisboundary would have a noticeable effect on the archipelago's glaciers and ice
caps. Svalbard's glaciers and ice caps are large enough to hold a few decimetres of sea
level equivalent, which, if released to the ocean, would have a significant impact on
low-lyingregions of the world, yet they are small enough that they react quite rapidly to
changes in climate. Since the late 1960ies, an annual glacier mass balance monitoring
programme of two glaciers (Austre Broggerbreen and midre Lovenbreen) has been
carried out by NPI. These two glaciers represent the longest continuous glacier mass
balance records from the Arctic. While low-lying glaciers along West Spitsbergen currently
are retreating, little is known about the status of the glaciers and ice caps further east on
Svalbard. Runoff measurements are made at some locations at the west coast of
Spitsbergen. Generally, the peak of spring melt occurs in early to mid-June. However,
severe rain events in the autumn can produce higher discharges, even though these runoff
events have much less duration. In Ny-Alesund, there is also regularly sampling of
sediment loads in Bayelva. In western Svalbard, the winter is commonly punctuated
by warm intervals during which moist, warm Atlantic air sweeps over the area. This air
mass producesheavy snow, slush, and rain as it converges with cold Arctic air. Liquid
water delivered to the snow surface percolated through the snow pack and freezes inside
the snow pack or at the soil surface. These events are important because significant
energy can be delivered to the base of the snow pack. Further, they represent a major
problem for reindeer since the ice layer may cover the moss and lichens. Within FAL, it
will be focused on mass balance investigations of glaciers and ice caps on Svalbard.
Innovative field programs and/or satellite remote sensing techniques that can provide
information of glacier mass balance over larger areas of Svalbard than made today are
particularly welcomed.Also, it is recommended that hydrological studies of water
balance and water quality should be carried out
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