Sentences with phrase «amplified by positive feedbacks»

The effect of these small orbital changes was amplified by positive feedbacks, such as changes in greenhouse gas levels.

The important point here is that a small external forcing (orbital for ice - ages, or GHG plus aerosols & land use changes in the modern context) can be strongly amplified by the positive feedback mechanism (the strongest and quickest is atmospheric water vapor - a strong GHG, and has already been observed to increase.

Not exact matches

If the audio output from the speaker is received again by the microphone, the initial audio signal is strongly amplified in a positive feedback loop.

The glacial retreat induced by this or any other process can be amplified by similar inverse positive feedbacks as for glacial advances.

«Also, if the atmosphere isn't accumulating heat at the rate forecast by the models, then the theoretical positive climate feedbacks which were expected to amplify the CO2 effect won't be as large,» McNider said.

This warming will be amplified by feedbacks (assuming a net positive feedback).

However, the greenhouse effect from water vapour is due to a (positive) feedback from the temperature and so any warming caused by CO2 is amplified by water vapour.

Water vapour is also the dominant positive feedback in our climate system and amplifies any warming caused by changes in atmospheric CO2.

Assuming that scientists haven't left out anything vital, this suggests that the net effect of water - based feedbacks is positive and would amplify GHG - induced warming by more than a factor of two.Many assumptions have been made, but the historical evidence increases our confidence in model results.

Its warming effect, however, is simultaneously amplified and dampened by positive and negative feedbacks such as increased water vapor (the most powerful greenhouse gas), reduced albedo, which is a measure of Earth's reflectivity, changes in cloud characteristics, and CO2 exchanges with the ocean and terrestrial ecosystems.

Research presented here and at other credible locations has shown CO2's effect to be logarithmic with possible offsetting by negative feedbacks rather than amplified greatly by positive feedback mechanisms.

The fact that the actual measured planetary warming is less than the lowest IPCC model prediction warming and is found only at high latitudes (which is not predicted by the IPCC models) logically supports the assertion that the planet's response to a change in forcing is to resist the change (negative feedback, planetary clouds in the tropics increase reflecting more sunlight in to space) rather than to amplify the change (positive feedback) due increased water vapour in the atmosphere.

Part of this sensitivity is attributed to a physically realistic positive radiative feedback, whereby a propensity toward higher cloud fractions in any given simulation is amplified by longwave radiative cooling.

Both casual relationships are operative at all times: In the 19th and 20th centuries, the temperature - driving CO2 causal relationship amplified the original temperature effect, as one of several factors leading to a net positive feedback on temperature due to CO2 increase, and a climate sensitivity of about 3C for a doubling of CO2 — a number verified multiple times by calculation from proxy data from multiple epochs in Earths prehistoric past.

In both scenarios the current global sink deteriorates after 2030, and by 2070 (ΔT ~ 2.5 °C over pre-industrial) the terrestrial biosphere becomes an increasing carbon source (Figure 4.2; see also Scholze et al., 2006) with the concomitant risk of positive feedback, developments that amplify climate change.

This triggers a positive feedback by lowering the albedo of the ocean's surface and leading to more of the Sun's light being absorbed, amplifying the warming.

Nonlinear interactions between the climate and biogeochemical systems could amplify (positive feedbacks) or attenuate (negative feedbacks) the disturbances produced by human activities.