Sentences with phrase «about climate sensitivity increase»

Not exact matches

They used two different climate models, each with a different sensitivity to carbon dioxide, to project California's future under two scenarios: an optimistic one, in which we only double the level of carbon dioxide in the atmosphere — since the 19th century we've already increased it by about a third — and a pessimistic scenario, in which we more than triple CO2.

Other ways that the standard or «consensus» calculations bias the climate sensitivity upward also exist and are also not negligible (or at least there is no scientific case that they are negligible), but for now it is sufficient to think about, and try to estimate, the magnitude of the increase in H2O and latent heat flow from surface to upper troposphere.

The addition says many climate models typically look at short term, rapid factors when calculating the Earth's climate sensitivity, which is defined as the average global temperature increase brought about by a doubling of CO2 in the atmosphere.

I think that the vast majority of lay readers who read the headlines and the text of stories on climate sensitivity do not know this and they simply presume that the scientists concerned are talking about their absolute best estimates of the possible temperature increases which may be faced.

2) The committed warming: effectively the greenhouse gas increase from pre-industrial to now has committed the planet to a surface warming of 2.4 °C (using IPCCs central value for climate sensitivity), and only about 0.6 °C of this has been realized thus far.

Regardless of what we think about D - O events, I am in complete agreement with Stefan that there is no evidence of any kind at present that the present climate suffers any kind of initial - condition sensitivity that would compromise the value of projections of response of statistical quantities to increases in GHG's.

If a doubling of CO2 resulted in a temperature increase of approximately 1 K before any non-Planck feedbacks (before water vapor, etc.), then assuming the same climate sensitivity to the total GHE, removing the whole GHE would result in about a (setting the TOA / tropopause distinction aside, as it is relatively small relative to the 155 W / m2 value) 155/3.7 * 1 K ~ = 42 K. Which is a bit more than 32 or 33 K, though I'm not surprised by the difference.

Even if climate sensitivity is somewhat less than the IPCC's median value of about 3 degrees Celsius, atmospheric carbon dioxide levels are increasing exponentially, so a smaller value merely buys an extra decade or two until the same amount of warming is reached.

Figure 1: If climate skeptics are right about climate sensitivity (green), then global average temperature increases will be more moderate this century, shown here for RCP6 (left) and RCP8.5 (right).

Scientists often talk about it in terms of the equilibrium climate sensitivity (ECS), which is the long - term temperature increase that we expect from a permanent doubling of atmospheric CO2.

Taking it into account, they then calculated the Earth's climate sensitivity and found that whenever CO2 levels doubled, we should see an increase in temperature of about 2 degrees Celsius (35.6 degrees Fahrenheit) above pre-industrial levels.

If climate skeptics are right about climate sensitivity (green), then global average temperature increases will be more moderate this century, shown here for RCP6 (left) and RCP8.5 (right).

Surely we can agree about the basics (radiative physics; likelihood that climate sensitivity is above 2C; impacts will likely increase with increased warming).

I estimate dT increased from 1980 to 2010 by about 0.4 K. Given equilibrium climate sensitivity of 0.75 K / Wm2, the amount of forcing neutralised by said dT is; 0.4 * 0.75 = 0.3 W / m2.

We know the planet will warm between about 1.5 and 4.5 °C in response to the increased greenhouse effect from a doubling of atmospheric carbon dioxide (the «climate sensitivity»).

And that says nothing about the fact that the Equilibrium Climate Sensitivity is supposed to reflect the rise in temperature following an increase in atmospheric CO2, but what is estimated is the rise in temperature PRECEEDING an increase in atmospheric CO2.

I'd be especially interested in hearing what you believe an increased role of natural variability in the 20th century record implies about climate sensitivity as well as the behavior of the anthropogenic signal «beneath» it.

But as yet does not seem interesting enough to make me think differently about the contribution of increased anthropogenic CO2 to the equilibrium climate sensitivity, or even the transient climate sensitivity.

The fact that the CMIP simulations ensemble mean can reproduce the 1970 — 2010 US SW temperature increase without inclusion of the AMO (the AMO is treated as an intrinsic natural climate vari - ability that is averaged out by taking an ensemble mean of individual simulations) suggests that the CMIP5 models» predicted US SW temperature sensitivity to the GHG has been significantly (by about a factor of two) overestimated.

Thinking about the problem in terms of temperature increase for a doubling of atmospheric CO2 (which we will probably exceed with current policies and energy trends), even studies that reinforce the skeptical narrative of low mean climate sensitivity leaves some chance of warming greatly exceeding international goals and historical boundaries (say a 5 percent chance of warming exceeding 4 °C).

«The fact that the CMIP simulations ensemble mean can reproduce the 1970 — 2010 US SW temperature increase without inclusion of the AMO (the AMO is treated as an intrinsic natural climate variability that is averaged out by taking an ensemble mean of individual simulations) suggests that the CMIP5 models» predicted US SW temperature sensitivity to the GHG has been significantly (by about a factor of two) overestimated.»

Girma, the equilibrium climate sensitivity (estimated at about 3C per CO2 doubling; or about 0.8 C per W / m ^ 2) is not related to the rate of increase, but to how far the increase goes until the Earth is back in energy balance.

This figure indicates 3 things: (1) the time lag between emitting greenhouse gases and when we see the principle effect is about 30 years, due mostly to the time required to heat the oceans, (2) the rate of temperature increase predicted by a climate sensitivity of 3 °C tracks well with the observed rate of temperature increase, and (3) we have already locked in more than 1.5 °C warming.

Since latent heat transport (and surface cooling of the ocean) must increase in proportion to the rate of evaporation, perhaps Wentz et al have identified a reason why the models appear to overstate climate sensitivity: the actual latent cooling increases by about 4 watts per square meter more than the models predict for each degree rise in surface temperature.

If the transient climate sensitivity to CO2 doubling is close to what Nic Lewis has calculated, and if the time required for CO2 to double is 140 years, and if the agricultural effects of short - term warming and CO2 increase are beneficial, then we can safely take actions independent of worries about CO2 production for the next 30 years or so.

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.

If we assume that the climate is equally sensitive to radiative forcing from each of these causes, the net increase of 1.2 watts should have brought about an increase in global mean temperature of 0.3 to 1.1 °C, depending on the climate sensitivity that is assumed.

One of the key drivers of tropospheric temperatures is sensible and latent heat flux from the largest climate energy source on the planet - the ocean — thus, the so - call hiatus tells us more about ocean cycles (ENSO & PDO) than about climate sensitivity to increasing GHG's.

Given the likelihood that the majority of the energy being accumulated in the climate system as a result of increased GH gases is being accumulated in the ocean (and no, not without measurable effect), I am wondering about even the relevancy of a tropospheric - centric metric for «climate» sensitivity?

When you have huge economic issues and great amounts of uncertainty with regard to things like sensitivity to a doubling of CO2, feedbacks from evaporation (including increases in clouds and their feedbacks), not to mention regarding consequences, then a legalisitic, «does climate change exist or not» approach isn't the right way to think about the issue.

I thought that the rough numbers were that the water vapor feedback about doubles the climate sensitivity from the no - feedback value and then the lapse rate feedback takes about half of that back, leaving about a 1.5X - or - so increase in the climate sensitivity.