On Thursday, Arnold Gordon, a Columbia University professor
of ocean stratification and circulation confirmed that it's most likely the one they're looking for.
Not exact matches
A new study says that climate - induced feedback loops could lead to a change in
ocean stratification and the more rapid melting
of ice sheets.
The marine geologist and first author
of the study explains, «Only in the short southern spring and summer, for just a few months in the year, was there a marked
stratification at the
ocean's surface.
With higher levels
of carbon dioxide and higher average temperatures, the
oceans» surface waters warm and sea ice disappears, and the marine world will see increased
stratification, intense nutrient trapping in the deep Southern
Ocean (also known as the Antarctic
Ocean) and nutrition starvation in the other
oceans.
One legitimate objection could be that they vertically mix heat into the
ocean more efficiently than the observations support (Forest [2008], Hansen [2011], & Kuhlbrodt & Gregory [2012]-RRB-, i.e they have weaker - than - observed surface
stratification - the black line bulge in Figure 3 (c) in the top 200 metres
of ocean.
Warming
of the
oceans will enhance thermal
stratification and density gradients, which will reduce vertical mixing.
Possible mechanisms include (vii) changes in
ocean temperature (and salinity), (viii) suppression of air - sea gas exchange by sea ice, and (ix) increased stratification in the Southern O
ocean temperature (and salinity), (viii) suppression
of air - sea gas exchange by sea ice, and (ix) increased
stratification in the Southern
OceanOcean.
One explanation (ix) conceived in the 1980s invokes more
stratification, less upwelling
of carbon and nutrient - rich waters to the surface
of the Southern
Ocean and increased carbon storage at depth during glacial times.
Ice shelves are important, because they play a role in the stability
of the Antarctic Ice Sheet and the ice sheet's mass balance, and are important for
ocean stratification and bottom water formation; this helps drive the world's thermohaline circulation.
•» According to Zhang (2007) thermal expansion in the lower latitude is unlikely because
of the reduced salt rejection and upper -
ocean density and the enhanced thermohaline
stratification tend to suppress convective overturning, leading to a decrease in the upward
ocean heat transport and the
ocean heat flux available to melt sea ice.
The warming
of the
oceans by sunlight, makes the daytime surface waters more bouyant than the cooler waters below and this leads to
stratification - a situation where the warmer water floats atop cooler waters underneath, and is less inclined to mix.
Stratification will reduce the return flow
of both carbon and nutrients from the deep
oceans to the surface.
Warming
of the
oceans leads to increased vertical
stratification (decreased mixing between the different levels in the
oceans), which would reduce CO2 uptake, in effect, reducing the oceanic volume available to CO2 absorption from the atmosphere.
There is a potential for both positive and negative feedbacks between the
ocean and atmosphere, including changes in both the physics (e.g., circulation,
stratification) and biology (e.g., export production, calcification)
of the
ocean.
In essence Zhang proposes that the warming factors reduce the growth
of sea ice which reduces
ocean overturning allowing increased
stratification of the
ocean which in turn reduces
ocean heat flux available to melt ice.
The rate
of this flux
of Atlantic Water heat flux is variable depending on depth
of the maximum and overlying
stratification (
stratification is controlled by salinity in the Arctic
Ocean).
The Arctic sea ice, for instance, has timescales
of around 5 years to a decade, and so a collapse
of summer ice cover could conceivably be reversed in a «cooling world» after only a decade or so (interactions with the Arctic
ocean stratification may make that take a little longer though).
One group
of researchers favors «
stratification» as a cause — the tendency
of climate warming
of the upper
ocean to restrict seasonal overturning and reduce the supply
of new atmospheric oxygen.
I understand this is mostly due to the isostatic pressure being the major factor in the
ocean's density profile resulting in a lot
of stratification.
On top
of that, warming increases
ocean stratification, which blocks the movement
of oxygen - rich surface waters to lower depths.
Climate change can influence the distribution
of dead zones by increasing water temperature and hence microbial activity, as well as reducing mixing
of the
ocean (i.e., increasing layering or stratification) of the Ocean — which have different temperatures, densities, salinities — and reducing mixing of oxygen - rich surface layers into the deeper parts of the O
ocean (i.e., increasing layering or
stratification)
of the
Ocean — which have different temperatures, densities, salinities — and reducing mixing of oxygen - rich surface layers into the deeper parts of the O
Ocean — which have different temperatures, densities, salinities — and reducing mixing
of oxygen - rich surface layers into the deeper parts
of the
OceanOcean.
Advancing the knowledge on the effects
of sea ice deformations on upper
ocean stratification and ecosystem will have profound implications on our ability to forecast ongoing changes in Arctic O
ocean stratification and ecosystem will have profound implications on our ability to forecast ongoing changes in Arctic
OceanOcean.
This study specifically considers the role
of Antarctic sea ice in shaping deep
ocean circulation and
stratification, by driving surface buoyancy loss associated with brine rejection (when sea ice forms, salt is pushed into the surrounding seawater, making it denser).
While it is tempting to attribute the unexplained sea ice trends to other factors such as increased upwelling
of relatively warm circumpolar deepwater (Thoma et al. 2008), an intensification
of the hydrological cycle and increased
ocean stratification (Liu and Curry 2010), or eastward propagation
of sea ice anomalies (Holland et al. 2005), the observed northerly wind trends (Fig. 5a) are qualitatively consistent with the decrease in sea ice in the 30 ° W — 60 ° W sector.
A warming surface
ocean is also likely to increase the density
stratification of the water column (i.e., Steinacher et al., 2010), altering the circulation and potentially increasing the isolation
of waters in an OMZ from contact with the atmosphere, hence increasing the intensity
of the OMZ.
About half
of the pCO2 decrease may be due to increased glacial
ocean stratification, trapping carbon - rich waters in the deep layers away from the atmosphere (22, 23).
Uncertainty in these projections due to potential future climate change effects on the
ocean carbon cycle (mainly through changes in temperature,
ocean stratification and marine biological production and re-mineralization; see Box 7.3) are small compared to the direct effect
of rising atmospheric CO2 from anthropogenic emissions.
A composite analysis
of satellite - based SST measurements reveals that in the tropical region the average strength
of the storm - induced sea surface cooling can be explained by the superposition
of an effect due to the storm intensity and an effect associated with the translation speed, and implies that the variability
of upper
ocean stratification may not be an important factor in this region
Another day, at the pub with my colleagues to celebrate a friend's PhD submission, I stirred my mojito with a straw and thought about
stratification of Southern
Ocean water masses.
The answer is in thermal expansion
of the
ocean waters, which was greater in the early Eocene than in the late Cretaceous, due to greater temperature
stratification of ocean water is the early Eocene versus the late Cretaceous.
The warming
of the surface
of the
ocean is thought to increase
stratification within the water column, preventing the nutrients in the cool
They will inevitably be affected by the increasing temperatures and thermal
stratification of the top layer
of the
ocean, since these are prime controls on their ecology, although it is not clear whether global warming would result in net increase or decrease
of coccolithophores.
Increased
stratification as the
ocean surface warms will decrease the upwellings
of nutrient - rich cold water, making
oceans less productive.
Without upwelling in the tropical
ocean the phytoplankton use up the N, P, and Fe in the sunlit layer and these nutrients are not replaced from below because
of thermal
stratification.
The warming
of the surface
of the
ocean is thought to increase
stratification within the water column, preventing the nutrients in the cool deep
ocean from rising to the surface.
Decreases in both upwelling and formation
of deep water and increased
stratification of the upper
ocean will reduce the input
of essential nutrients into the sunlit regions
of oceans and reduce productivity (Cox et al., 2000; Loukos et al., 2003; Lehodey et al., 2003; Sarmiento et al., 2004a).
A quantitative theoretical model
of the meridional overturning circulation and associated deep
stratification in an interhemispheric, single - basin
ocean with a circumpolar channel is presented.
The sea is not only warming, leading to higher
stratification and thus lower ventilation
of the deep
ocean, it also is becoming more acidic.
The combined effects
of wind, geometry, and diffusion on the
stratification and circulation
of the
ocean are explored by numerical and analytical methods.