Sentences with phrase «increased poleward»

Most of the observed decline in the latitudinal temperature gradient during the Pliocene can be explained by increased poleward heat transport.

However, the mechanism of increased poleward heat transport can not be the only physical mechanism driving the reduced temperature gradient because it is in fact the surface temperature gradient that ultimately drives the flux of heat poleward.

Several mechanisms have been hypothesized to explain this reduced temperature gradient, including increased poleward heat transport, decreased ice albedo, and changes in cloud cover (Fedorov et al., 2006).

In which case, half of the global warming in the last three decades is due to the negative feedback of increased poleward oceanic heat transport as a result of weaker solar activity.

However periodically due to increased poleward heat flux the winds slacken around the polar vortex and may even reverse direction and flow instead from east to west.

Numerous recent studies based on both observations and model simulations indicate that reduced Barents - Kara sea ice in late fall favors a strengthened and northwestward expansion of the Siberian high, increased poleward heat flux, weakened polar vortex, and ultimately a negative AO.

The area of tropical forest was almost certainly less as so much of the tropics had dried out; but yes, the global distribution of the forest had increased poleward.

So in Greenland it got warmer both because of higher CO2, more sunlight at high latitudes during summer, AND because of increased poleward heat flow.

Then there is the increased poleward flow of the ocean currents — partly driven by Hurricanes, I understand.

That should increase poleward flows in the lower stratosphere / higher troposphere.

Reduction in ice free area, a positive feedback to the atmosphere increases poleward ocean heat transport, a negative feedback for the oceans.

The post 1995 AMO and Arctic warming is the natural response to the decline in solar wind pressure since then, by it increasing negative NAO / AO conditions, and thereby increasing the poleward heat transports.

They forced the model with CO2 and happened to catch it when it was in the process of increasing poleward ocean heat transport.

Take solar vs. GHGs: 1.5 W / m2 solar change (TOA) over a solar cycle has a large effect in the stratosphere: During a solar cycle, the largest change is in the short waves: 10 % more during high solar activity: that affects ozone building, the temperature in the stratosphere and increases the polewards flow in the stratosphere.

These oscillations are superimposed on a long term trend of increasing poleward ocean heat transport.

There is also an increasing poleward transport of water vapour from lower latitudes.

It is refilled by the coldness of the poles, and artificial pumping, which will increase poleward warm currents (by mechanical pushing), will warm the arctic by pushing more warm equatorial water towards the poles.

Not exact matches

A poleward expansion of the tropics is likely to bring even drier conditions to these heavily populated regions, but may bring increased moisture to other areas.

So there is evidence that the birds can bounce back, and the team's modelling indicates that they will very probably try to adapt to their changing circumstances by colonisation Bouvet Island, and by increasing their numbers on Heard and South Georgia islands, which should benefit from improved foraging conditions as the APF edges ever poleward.

This study found that associated with a poleward shift of the subtropical jet in the North Pacific basin, the number of atmospheric river days increases much more significantly in Alaska during spring because both increased moisture and increased wind speed gang up to increase the frequency of atmospheric rivers.

Meanwhile, increasing temperature and ocean warming may lead to the reduction of diatom production as well as cell size, inducing poleward shifts in the biogeographic distribution of diatoms.

For example, they predicted the expansion of the Hadley cells, the poleward movement of storm tracks, the rising of the tropopause, the rising of the effective radiating altitude, the circulation of aerosols in the atmosphere, the modelling of the transmission of radiation through the atmosphere, the clear sky super greenhouse effect that results from increased water vapor in the tropics, the near constancy of relative humidity, and polar amplification, the cooling of the stratosphere while the troposphere warmed.

What we * do * suggest is that the weakened poleward temperature gradient owing to the rapidly warming Arctic relative to mid-latitudes (Arctic amplification) should increase the north - south component of the upper - level flow, making highly wavy jet - stream patterns (like the one this winter) more likely.

Their abstract says «energy budget calculations show that poleward atmospheric energy transport increases more in solar forcing compared to equivalent CO2 forcing simulations, which is in line with the identified strong increase in large - scale precipitation in solar forcing scenarios.»

In any case, ocean data showed a slight slowing of the poleward water transport, not the increase that the AMO explanation called for.

Suppose that there has been a multi-century increase in the poleward heat transport in the oceans due to internal variability, which warms the poles, reduces ice extent and albedos, and thereby warms the planet.

Losing ice, reducing the poleward temperature gradient, and warming the entire climate system should contribute to increasing the likelihood of anomalous storms.

Of course, there are plenty of negative feedbacks as well (the increase in long wave radiation as temperatures rise or the reduction in atmospheric poleward heat flux as the equator - to - pole gradient decreases) and these (in the end) are dominant (having kept Earth's climate somewhere between boiling and freezing for about 4.5 billion years and counting).

Other aspects of global warming's broad footprint on the world's ecosystems include changes in the abundance of more than 80 percent of the thousands of species included in population studies; major poleward shifts in living ranges as warm regions become hot, and cold regions become warmer; major increases (in the south) and decreases (in the north) of the abundance of plankton, which forms the critical base of the ocean's food chain; the transformation of previously innocuous insect species like the Aspen leaf miner into pests that have damaged millions of acres of forest; and an increase in the range and abundance of human pathogens like the cholera - causing bacteria Vibrio, the mosquito - borne dengue virus, and the ticks that carry Lyme disease - causing bacteria.

Current work1 has provided evidence of the increase in frequency and intensity of winter storms, with the storm tracks shifting poleward, 2,3 but some areas have experienced a decrease in winter storm frequency.4 Although there are some indications of increased blocking (a large - scale pressure pattern with little or no movement) of the wintertime circulation of the Northern Hemisphere, 5 the assessment and attribution of trends in blocking remain an active research area.6 Some recent research has provided insight into the connection of global warming to tornadoes and severe thunderstorms.7, 8

The cooler Arctic then promoted formation of North Atlantic Deep Water (NADW in the upper frame of Figure 13) as salty Atlantic waters transported poleward cooled and brine rejection increased as more Arctic sea ice formed.

However, there is also the expansion of the Hadley Cells where water vapor from tropical ocean evaporation rises, water in the form of rain falls out as the air cools with increased altitude, then dry air descends at poleward edge of the cells in the dry subtropics.

Most models reasonably represent the poleward increase of reflected shortwave radiation in the mid-latitudes of the northern hemisphere, presumably because part of this is carried by the influence of specified surface features such as the Saharan desert and Tibetan Plateau.

Conversely, during low solar activity during the Little Ice Age, transport of warm water was reduced by 10 % and Arctic sea ice increased.17 Although it is not a situation I would ever hope for, if history repeats itself, then natural climate dynamics of the past suggest, the current drop in the sun's output will produce a similar cooler climate, and it will likely be detected first as a slow down in the poleward transport of ocean heat.22 Should we prepare for this possibility?

Direct effects of increasing temperature on marine and freshwater ecosystems are already evident, with rapid poleward shifts in regions, such as the north - east Atlantic, where temperature change has been rapid (see Chapter 1).

According to the report, some of the small mammals have recently acquired new parasites, indicating poleward shifts of sub-Arctic faunas and increases in biodiversity.

Poleward and / or more zonal jetstreams mean that the troposphere is bit warmer as the rate of energy flow through the troposphere increases.

Precipitation observations over land show the expected general increase of precipitation poleward of the subtropics and decrease at lower latitudes [1], [26].

This is associated with a poleward shift of the westerlies at the surface (see Section 10.3.6) and in the upper troposphere particularly notable in the Southern Hemisphere (SH)(Stone and Fyfe, 2005), and increased relative angular momentum from stronger westerlies (Räisänen, 2003) and westerly momentum flux in the lower stratosphere particularly in the tropics and southern mid-latitudes (Watanabe et al., 2005).

Before 2006, our warm salt subduction mechanism does not allow the Atlantic to cool when its subpolar salinity was increasing, because poleward transport of warm salty water and increasing subpolar subduction are parts of the same mechanism of enhanced AMOC upper - ocean transport.

Those changes are reflected in the equatorward movement of the jet streams and increasing dominance of poleward high pressure cells.

All of the warming since the LIA can easily be explained by increases in poleward ocean heat transport.

A wide range of other observations (such as reduced Arctic sea ice extent and increased ocean heat content) and indications from the natural world (such as poleward shifts of temperature - sensitive species of fish, mammals, insects, etc.) together provide incontrovertible evidence of planetary - scale warming.

The poleward shift of the Southern Hemisphere middle latitude jetstream in response to increasing carbon dioxide is one of the most robust circulation responses found in climate change experiments, and is predicted to occur during all seasons (IPCC, 2007c).

If surface temperatures were correlated positively with latitude, and temperature increased, one would expect a poleward shift of oceanic biota.

Any excess at the tropics would get shifted poleward and increase L relative to DLR away from the tropics.

The current cooling phase has been accompanied by an increase in size of the poleward high pressure systems and a sinking equatorward of the jet streams in both hemispheres.

The air circulation systems in both hemispheres move poleward and the ITCZ moves further north of the equator as the speed of the hydrological cycle increases due to the cooler stratosphere increasing the temperature differential between stratosphere and surface.

A robust feature of the response of climate models to increases in atmospheric concentrations of greenhouse gases is the poleward retreat of terrestrial snow and sea ice, and the polar amplification of increases in lower - tropospheric temperature.

back to the horizontal gradient, if the upper tropospheric thermal wind shear increase is greater than the decrease of the lower layer, then maybe the overall baroclinic instability would be stronger — but currently the upper level eddy circulations do not transport much heat poleward, so would the structure of cyclones change so that a deeper layer of air is involved in the thermal advection, compensating for a weaker temperature gradient?