Sentences with phrase «mean radiative»

Now I get that «RF» may mean radiative forcing.

Global mean temperature changes are driven by the global mean radiative forcing (RF) caused by each emitted compound.

Or, the difference between the worst case IPCC scenario and the best conceivable «alternative scenario» by 2050 is only about 1 W / m2 mean radiative energy imbalance.

Therefore, the total annual and global mean radiative forcing during the LGM is likely to have been approximately — 8 W m — 2 relative to 1750, with large seasonal and geographical variations and significant uncertainties (see Section 6.4.1).

The calculated global mean radiative forcing ranges from -0.26 to -0.82 Wm - 2, although most lie in the range -0.26 to -0.4 Wm - 2.

The traditional global mean radiative forcing provides no information about this regional structure, so many researchers have begun to present estimates of radiative forcing on a regional scale as derived from models or observational campaigns.

The direct radiative forcing (DRF) is strongest in the Northern Hemisphere summer when the insolation is the highest although different seasonal cycles of the sulphate burden from the chemical transport models result in maximum global mean radiative forcings ranging from May to August (e.g., Haywood and Ramaswamy, 1998), the ratio of the June - July - August / December - January - February radiative forcing being estimated to lie in the range less than 2 (e.g., van Dorland et al., 1997) to > 5 (e.g., Penner et al., 1998b; Grant et al., 1999) with a mean of approximately 3.3.

«regional variations in radiative forcing may have important regional and global climate implications that are not resolved by the concept of global mean radiative forcing.»

Like the other metrics discussed above, global mean radiative forcing at the surface would not allow characterization of the regional structure of forcing.

It is found that the stability and sensitivity properties of the ZDM and Model A are very similar, both depending only on the global - mean radiative response coefficient and the global - mean forcing.

Phil The time spent by an individual molecule in a particular state is extremely small at atmospheric conditions, orders of magnitude less than the mean radiative lifetime which is why emission is extremely unlikely, and most of the energy ends up thermalized.

Since the mean radiative forcing progression in RCP 8.5 is likely steeper than the radiative forcing progression of the recent past, this finding can not be used to suggest that models are overestimating the response to forcings and it can not be used to infer anything about future rates of warming.

Thus in the second order approximation, the Earth's global temperature depends linearly on both the mean radiative forcing and the standard deviation of radiative forcing.

The term «climate sensitivity» refers to the steady - state increase in the global annual mean surface air temperature associated with a given global mean radiative forcing.

If you mean radiative disequilibrium, I guess this is would be highly model - dependent (like the OHC change).

http://www.springerlink.com/content/lm0024kv72t3841w/ «The simulated magnitude of hydrological changes over land are much larger when compared to changes over oceans in the recent marine cloud albedo enhancement study since the radiative forcing over land needed (− 8.2 W m − 2) to counter global mean radiative forcing from a doubling of CO2 (3.3 W m − 2) is approximately twice the forcing needed over the oceans (− 4.2 W m − 2).

Therefore, the total annual and global mean radiative forcing during the LGM is likely to have been approximately — 8 W m — 2 relative to 1750, with large seasonal and geographical variations and significant uncertainties (see Section 6.4.1).

(Top left) Global annual mean radiative influences (W m — 2) of LGM climate change agents, generally feedbacks in glacial - interglacial cycles, but also specified in most Atmosphere - Ocean General Circulation Model (AOGCM) simulations for the LGM.

18.4wm - 2 higher assuming the same albedo means a radiative forcing of 3.23wm - 2, which is almost the forcing you get from doubling of CO2 or increasing solar output by 2 %.

You write: «If internal variability (such a a cool PDO phase) reduces the rate of increase of surface temperature, while the e [x] ternal forcing still is increasing, this means the radiative imbalance is impeded from being cancelled by surface warming.»

If internal variability (such a a cool PDO phase) reduces the rate of increase of surface temperature, while the eternal forcing still is increasing, this means the radiative imbalance is impeded from being cancelled by surface warming.

Not exact matches

That means Fan's radiative cooling panels could theoretically be substituted on rooftops where existing solar panels feed electricity to air conditioning systems needed to cool the building.

Tsushima, Y., A. Abe - Ouchi, and S. Manabe, 2005: Radiative damping of annual variation in global mean surface temperature: Comparison between observed and simulated feedback.

He then uses what information is available to quantify (in Watts per square meter) what radiative terms drive that temperature change (for the LGM this is primarily increased surface albedo from more ice / snow cover, and also changes in greenhouse gases... the former is treated as a forcing, not a feedback; also, the orbital variations which technically drive the process are rather small in the global mean).

To contribute to an understanding of the underlying causes of these changes we compile various environmental records (and model - based interpretations of some of them) in order to calculate the direct effect of various processes on Earth's radiative budget and, thus, on global annual mean surface temperature over the last 800,000 years.

The importance of orbital variations, of the greenhouse gases CO2, CH4 and N2O, of the albedo of land ice sheets, annual mean snow cover, sea ice area and vegetation, and of the radiative perturbation of mineral dust in the atmosphere are investigated.

Abstract:» The sensitivity of global climate with respect to forcing is generally described in terms of the global climate feedback — the global radiative response per degree of global annual mean surface temperature change.

Ice sheet albedo forcing is estimated to have caused a global mean forcing of about — 3.2 W m — 2 (based on a range of several LGM simulations) and radiative forcing from increased atmospheric aerosols (primarily dust and vegetation) is estimated to have been about — 1 W m — 2 each.

However, global mean precipitation is controlled not by the availability of water vapour, but by a balance between the latent heat of condensation and radiative cooling in the troposphere.

The estimated difference between the present - day solar irradiance cycle mean and the Maunder Minimum is 0.08 % (see Section 2.7.1.2.2), which corresponds to a radiative forcing of about 0.2 W m — 2, which is substantially lower than estimates used in the TAR (Chapter 2).

As long as the temporal pattern of variation in aerosol forcing is approximately correct, the need to achieve a reasonable fit to the temporal variation in global mean temperature and the difference between Northern and Southern Hemisphere temperatures can provide a useful constraint on the net aerosol radiative forcing (as demonstrated, e.g., by Harvey and Kaufmann, 2002; Stott et al., 2006c).

Or does he perhaps mean that slow components, like the ocean, modulate the clouds, and the resulting cloud radiative forcing amplifies or damps the resulting interannual or decadal variability?

It's a theory now substantiated by physics and observations regarding total radiative forcing and sensitivity, and in our current case of warming attributable to increased forcing agents form human / industrial means we are experiencing a change in trends pertaining to weather events driven by total change factors.

While the local, seasonal climate forcing by the Milankovitch cycles is large (of the order 30 W / m2), the net forcing provided by Milankovitch is close to zero in the global mean, requiring other radiative terms (like albedo or greenhouse gas anomalies) to force global - mean temperature change.

We suggest that means setting some goals in terms of concentrations (or, even better perhaps, radiative forcing).

One can see a number of basic flaws here; the complete lack of appreciation of the importance of natural variability on short time scales, the common but erroneous belief that any attribution of past climate change to solar or other forcing means that CO2 has no radiative effect, and a hopeless lack of familiarity of the basic science of detection and attribution.

The fact that there is a natural greenhouse effect (that the atmosphere restricts the passage of long wave (LW) radiation from the Earth's surface to space) is easily deducible from i) the mean temperature of the surface (around 15ºC) and ii) knowing that the planet is roughly in radiative equilibrium.

As for Wielecki, I'm not sure which red graph you are referring to, but if you mean the one at the top of the three - panel graph from the corrected version of the Science article, that is labeled «LW,» which, as I said in my response to Spencer Weart that is the TOA longwave radiative forcing.

(This just shows that while the stratosphere as a whole may be in radiative equilibrium, i.e., energy transfer is primarily by radiative means, there are some locations in the stratosphere where dynamic energy transport is also significant.)

This means that there has been very little actual global warming (or net TOA radiative imbalance) in these seven years.

The global mean aerosol radiative forcing caused by the ship emissions ranges from -12.5 to -23 mW / m ^ 2, depending on whether the mixing between black carbon and sulfate is included in the model.

Abstract:» The sensitivity of global climate with respect to forcing is generally described in terms of the global climate feedback — the global radiative response per degree of global annual mean surface temperature change.

Moreover, some have argued that a strong aerosol radiative forcing means that the climate sensitivity has to be -LSB-...]

It's painfully easy to paint oneself logically into a corner by arguing that either (i) vigorous natural variability caused 20th century climate change, but the climate is insensitive to radiative forcing by greenhouse gases; or (ii) the climate is very sensitive to greenhouse gases, but we still are able to attribute details of inter-decadal wiggles in the global mean temperature to a specific forcing cause.

If this holds through the entire year, this also means that there is not a «statistically signifiant» TOA radiative imbalance through this period.

So for example deglaciation warmed global mean temps by about 5 C over 10k years with a radiative forcing of about 6.5 W / m2 (total of both GHG increases and albedo decreases).

The main changes in radiative forcing from the precessional cycle are in the latitudinal and seasonal distribution, not in the global mean, which is why the nature of the response can be expected to be different from doubling CO2.

As for your question about hurricanes, the argument given for the global mean hydrological cycle doesn't apply to the hurricane because the global mean argument assumes an equilibrium between radiative cooling and latent heat release.

Because latent heat release in the course of precipitation must be balanced in the global mean by infrared radiative cooling of the troposphere (over time scales at which the atmosphere is approximately in equilibrium), it is sometimes argued that radiative constraints limit the rate at which precipitation can increase in response to increasing CO2.

Pick some density d - saturated moles / m ^ 3 that effectively means the gas is saturated as far as radiative transfer is concerned.