Sentences with phrase «negative feedback sensitivity»

An alternative mechanism involves heightened negative feedback sensitivity to glucocorticoids in the hippocampus following exposure to elevated cortisol levels early in development, which would inhibit CRH production in the hypothalamus and, ultimately, lead to lower cortisol levels over time (56).

Not exact matches

Google understands this sensitivity and teaches its supervisors to be consistent (free from bias) when delivering feedback across their teams, to balance positive (motivational) and negative (developmental) feedback, to be authentic and appreciative, and to state growth opportunities in a clear, compassionate way.

I'm not even an amateur climate scientist, but my logic tells me that if clouds have a stronger negative feedback in the Arctic, and I know (from news) the Arctic is warming faster than other areas, then it seems «forcing GHGs» (CO2, etc) may have a strong sensitivity than suggested, but this is suppressed by the cloud effect.

A sensitivity which is too low will be inconsistent with past climate changes - basically if there is some large negative feedback which makes the sensitivity too low, it would have prevented the planet from transitioning from ice ages to interglacial periods, for example.

So the reference system climate sensitivity parameter is based on a negative feedback due to Stefan's law.

On sensitivity positive and negative feedbacks: Since the temps are pushing the upper bounds of the estimated ranges, one could say reasonably that what we don't know has more in common with the speed of the feedbacks, not the question of CO2 sensitivity as you infer.

Olympus Mons, What it would take is a new model that explained climate better than the current one and a) had a CO2 sensitivity lower than 1 degree per doubling; or b) had a large negative feedback that somehow kicked in right at the current terrestrial temperature range; or c) had a mechanism whereby CO2 suddenly stopped being a greenhouse gas at 280 ppmv

Two degrees is the lowest climate sensitivity possible without negative feedbacks.

I suspect you are confusing sensitivity with feedback, e.g. the controversial claims that water vapour feedback may be negative.

David@288, I'm just going with physics, and I don't see how you get enough negative feedback to get a negative sensitivity AND get 33 degrees of warming over Earth's blackbody temperature.

David Benson, Based solely on the fact that Earth was 33 degrees warmer than its blackbody temperature, on what was known of the absorption spectrum of CO2 and on the fact that Earth's climate did not exhibit exceptional stability characteristic of systems with negative feedback, I'd probably still go with restricting CO2 sensitivity to 0 to + infinity.

SM, what I am saying is that if you had negative sensitivity, that would imply strong negative feedback, and you wouldn't see much change in the climate system — in contrast to the climate we see on Earth.

(Orbital forcing doesn't have much of a global annual average forcing, and it's even concievable that the sensitivity to orbital forcing as measured in terms of global averages and the long - term response (temporal scale of ice sheet response) might be approaching infinity or even be negative (if more sunlight is directed onto an ice sheet, the global average albedo might increase, but the ice sheet would be more likely to decay, with a global average albedo feedback that causes warming).

An important takeaway point from this is that with a low climate sensitivity (i.e. one with limited positive feedbacks, or counterbalancing negative feedbacks), then the ice ages can't happen.

Depending on meridional heat transport, when freezing temperatures reach deep enough towards low - latitudes, the ice - albedo feedback can become so effective that climate sensitivity becomes infinite and even negative (implying unstable equilibrium for any «ice - line» (latitude marking the edge of ice) between the equator and some other latitude).

The feedback can become zero — or to avoid confusion regarding what is and is not a feedback — the equilibrium climate sensitivity can become infinite (or negative) in some conditions.

Spencer's claim of low sensitivity and negative feedbacks is based on this test, which is actually a test of models» ability to reproduce ENSO, and based on his internal variability hypothesis, which as noted above, Dessler's paper has also put to rest.

Climate Myth: Climate sensitivity is low «His [Dr Spencer's] latest research demonstrates that — in the short term, at any rate — the temperature feedbacks that the IPCC imagines will greatly amplify any initial warming caused by CO2 are net - negative, attenuating the warming they are supposed to enhance.

Cumulus clouds will have the same effect, but more in balance with the positive effects, resulting in less negative net feedback, but with the same result, much lower climate sensitivity than the IPCC would have you believe.I realize that climate sensitivity is not usually discussed as a local phenomenon, but it should be, since it is the integral of all local phenomena.

Ultimately our paper shows that all three of the main conclusions in DK12 are faulty: the rate of OHC increase has not slowed in recent years, there is no evidence for «climate shifts» in global heat content data, and the recent OHC data do not support the conclusion that the net climate feedback is negative or that climate sensitivity is low.

Sensitivity is related to climate feedbacks and has to do with the amount of positive or negative forcing that occurs in response to a given climate forcing.

DK12 used ocean heat content (OHC) data for the upper 700 meters of oceans to draw three main conclusions: 1) that the rate of OHC increase has slowed in recent years (the very short timeframe of 2002 to 2008), 2) that this is evidence for periods of «climate shifts», and 3) that the recent OHC data indicate that the net climate feedback is negative, which would mean that climate sensitivity (the total amount of global warming in response to a doubling of atmospheric CO2 levels, including feedbacks) is low.

The evidence supports a higher sensitivity to CO2 in the cryosphere, suggesting a negative feedback by H2O, that prevents CO2 from having the same effect elsewhere.

The difference is probably enough to transform clouds from having a slight positive feedback to a slight negative feedback which in turn would lower climate sensitivity to CO2 doublings from 2 - 5C to 1C.

I think what you are objecting to is the idea of one sensitivity that that can be projected to higher levels of forcing without considering that the negative feedbacks may become more vigorous and diminish or effectively cap it.

Evans of course provides no evidence for his proclaimed warming dampening (a.k.a. negative feedback and low climate sensitivity).

There is much discussion as to the value of the climate sensitivity, which swirls around whether there is net positive or negative feedback from things like clouds and water vapor.

By arguing the «hot spot» doesn't exist, Evans is contradicting his previous claims about negative feedbacks and low climate sensitivity.

Land temp rises more because it tends to be dry, especially in winter in higher latitudes, and thus lapse rate feedback (which is negative) doesn't play as large a role in reducing CO2 sensitivity.

However, I am not a «warmista» by any means — we do not know how to properly quantify the albedo of aerosols, including clouds, with their consequent negative feedback effects in any of the climate sensitivity models as yet — and all models in the ensemble used by the «warmistas» are indicating the sensitivities (to atmospheric CO2 increase) are too high, by factors ranging from 2 to 4: which could indicate that climate sensitivity to a doubling of current CO2 concentrations will be of the order of 1 degree C or less outside the equatorial regions (none or very little in the equatorial regions)- i.e. an outcome which will likely be beneficial to all of us.

[37] This hypothesis suggests a negative feedback which would counter the effects of CO2 warming by lowering the climate sensitivity.

They are not, however, part of the (self - proclaimed) larger group who simultaneously say that AGW can't be falsified even as they say that valid theories / hypotheses must be falsifiable even as they say that they don't doubt that that the basic AGW theory / hypothesis is valid (they only doubt the magnitude of the sensitivity and / or negative feedback).

A continuing negative feedback carbon cycle response, in conjunction with restraint on human emissions, plus some luck with experiencing the lower ranges of climate sensitivity, could lead to climate change of, let's say, 2 °C.

He has published two papers stating that climate change is not serious: a 2001 paper hypothesizing that clouds would provide a negative feedback to cancel out global warming, and a 2009 paper claiming that climate sensitivity (the amount of warming caused by a doubling of carbon dioxide) was very low.

The «Physical Science» report finds that negative feedbacks in the climate system reduce the model model derived temperature sensitivity to values an order of magnitude smaller.

Climate sensitivity is somewhat uncertain as there are remaining scientific uncertainties about the magnitude of the positive and negative feedbacks in the climate system.

-- Lindzen & Choi (2009/2011) show a low overall climate sensitivity (overall negative feedback) based on CERES satellite observations

But the regional effects can potentially contribute to a much lower global sensitivity than people would expect if they intuitively assumed that sensitivity (with «feedbacks») can't be negative.

Some of them deny it is even warming, others claim anthropogenic global warming (AGW) is a hoax, others claim that there is some magical negative feedback that will result in virtually no warming, others like Lewis cherry pick literature to delude themselves into thinking that climate sensitivity is low, while others are convinced that an ice age is imminent;)

My bet, climate sensitivity to a doubling of CO2 is a lot less than the IPCC's 1.1 C, love to see papers published on negative feedbacks.

There is a high climate sensitivity to temperature with negative, stable, feedback that does not respond to the steady increase of CO2.

Logically, when water vapor is added the initial «sensitivity» is positive since none of the phenomena associated with negative feedbacks from water vapor would exist.

Cumulus clouds will have the same effect, but more in balance with the positive effects, resulting in less negative net feedback, but with the same result, much lower climate sensitivity than the IPCC would have you believe.

Changes in cloudiness in a warmer climate can be either a negative or positive feedback and the uncertainty in this feedback is the major source of uncertainty in the IPCC's estimate of climate sensitivity.

He ignored that it is a negative feedback to climate sensitivity, for which he gave IPCC's open loop values.

Gavin & IPCC never read Einstein's directive, and missed a major simplifying option: Negative feedback and low climate sensitivity!

If someone thought that the net effect was a small «negative feedback» would that require a sensitivity below 1.2 C?

Nope, e.g Lindzen & Choi ERBE observations show net feedbacks are negative, sensitivity almost zero -LRB-.18 C).

Regarding climate sensitivity I speculate that the ESLD - effect might cause underestimation of cloud feedback and aerosol negative forcing.

Models agree that the net cloud feedback is strongly positive, mainly because (my understanding) it was impossible to simulate features of the 20th century climate in models with neutral or negative cloud feedbacks (or, perhaps I should just say, models with a low climate sensitivity).