Sentences with phrase «such radiative forcing»

In order to reach such radiative forcing levels, greenhouse gas emissions (and indirectly emissions of air pollutants) are reduced substantially, over time (Van Vuuren et al. 2007a).

Would such radiative forcing be evident given what we know about planet Earth?

Not exact matches

Several explanations for this widening have been proposed, such as radiative forcing due to greenhouse gas increase and stratospheric ozone depletion.

(C) potential metrics and approaches for quantifying the climatic effects of black carbon emissions, including its radiative forcing and warming effects, that may be used to compare the climate benefits of different mitigation strategies, including an assessment of the uncertainty in such metrics and approaches; and

It is this empirical property that makes radiative forcing and climate sensitivity such useful concepts.

Similarly, many studies that attempt to examine the co-variability between Earth's energy budget and temperature (such as in many of the pieces here at RC concerning the Spencer and Lindzen literature) are only as good as the assumptions made about base state of the atmosphere relative to which changes are measured, the «forcing» that is supposedly driving the changes (which are often just things like ENSO, and are irrelevant to radiative - induced changes that will be important for the future), and are limited by short and discontinuous data records.

Could the climate forcing itself, such as increasing GHGs, affect parameterizations independently of the larger scale climate changes (for example, by changing thermal damping of various kinds of waves, or by changing the differences of radiative effects between different amounts and kinds of clouds)?

Earth's energy balance In response to a positive radiative forcing F (see Appendix A), such as characterizes the present - day anthropogenic perturbation (Forsteret al., 2007), the planet must increase its net energy loss to space in order to re-establish energy balance (with net energy loss being the difference between the outgoing long - wave (LW) radiation and net incoming shortwave (SW) radiation at the top - of - atmosphere (TOA)-RRB-.

Mike's work, like that of previous award winners, is diverse, and includes pioneering and highly cited work in time series analysis (an elegant use of Thomson's multitaper spectral analysis approach to detect spatiotemporal oscillations in the climate record and methods for smoothing temporal data), decadal climate variability (the term «Atlantic Multidecadal Oscillation» or «AMO» was coined by Mike in an interview with Science's Richard Kerr about a paper he had published with Tom Delworth of GFDL showing evidence in both climate model simulations and observational data for a 50 - 70 year oscillation in the climate system; significantly Mike also published work with Kerry Emanuel in 2006 showing that the AMO concept has been overstated as regards its role in 20th century tropical Atlantic SST changes, a finding recently reaffirmed by a study published in Nature), in showing how changes in radiative forcing from volcanoes can affect ENSO, in examining the role of solar variations in explaining the pattern of the Medieval Climate Anomaly and Little Ice Age, the relationship between the climate changes of past centuries and phenomena such as Atlantic tropical cyclones and global sea level, and even a bit of work in atmospheric chemistry (an analysis of beryllium - 7 measurements).

In this way, the response of LW fluxes (PR) and convection (CR) tend to spread the temperature response vertically from where forcings occur — not generally eliminating the effect of RF distribution over height, although in the case with convection driven by differential radiative heating within a layer, CR can to a first approximation evenly distribute a temperature response over such a layer.

Secondly, unlike the global average surface temperature trend, which has a lag with respect to radiative forcing, there is no such lag when heat content is measured in Joules (see http://blue.atmos.colostate.edu/publications/pdf/R-247.pdf).

Where you then have a talik, from this combination of geological and radiative forces, and then there is plenty of free gas underneath that can migrate out easily through pathways once there are such tears, and then you add on top of all that that it is a seismically active zone, one can easily see how global warming could greatly amplify the effects of an earthquake at that fault zone.

Obviously, sensitivity to radiative forcing of greenhouse gases (not water vapor, but CO2 and CH4) can't include feedbacks of those same gases — those are defined as forcings in such a sensitivity.

To be sure, some of these effects (such as the impact of irrigation on surface water vapour, or land use changes on evapotranspiration) are not easily dealt with in terms of the tropospheric radiative forcing — a point that was well made in the National Academies report on radiative forcing (on which Dr. Pielke was an author).

[Response: VEI is a geologically - based index and as such is not favored in quantitative reconstructions of radiative forcing.

First, for changing just CO2 forcing (or CH4, etc, or for a non-GHE forcing, such as a change in incident solar radiation, volcanic aerosols, etc.), there will be other GHE radiative «forcings» (feedbacks, though in the context of measuring their radiative effect, they can be described as having radiative forcings of x W / m2 per change in surface T), such as water vapor feedback, LW cloud feedback, and also, because GHE depends on the vertical temperature distribution, the lapse rate feedback (this generally refers to the tropospheric lapse rate, though changes in the position of the tropopause and changes in the stratospheric temperature could also be considered lapse - rate feedbacks for forcing at TOA; forcing at the tropopause with stratospheric adjustment takes some of that into account; sensitivity to forcing at the tropopause with stratospheric adjustment will generally be different from sensitivity to forcing without stratospheric adjustment and both will generally be different from forcing at TOA before stratospheric adjustment; forcing at TOA after stratospehric adjustment is identical to forcing at the tropopause after stratospheric adjustment).

With climate change of course, we have no such confidence, because of the enormous and rapid increase in GHGs, whose physical basis as a radiative forcing agent is well understand, and quantified.

«Radiative forcing Radiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m — 2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the SuRadiative forcing Radiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m — 2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the SuRadiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m — 2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the Suradiative flux (expressed in W m — 2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the Sun.»

Between 1990 and 2015, the bulletin says, there was a 37 percent increase in radiative forcing — the warming effect on the climate — because of long - lived greenhouse gases such as carbon dioxide, methane and nitrous oxide from industrial, agricultural and domestic activities.

For instance, what is the usual response of a CAGW movement supporter to learning that, under their own climate sensitivity assumptions, other forms of geoengineering than CO2 cutbacks could neutralize the predicted warming for < = ~ 1 % the cost and with lesser biological side - effects (such as stratospheric dispersion of micron - scale reflective dust staying suspended for months at appropriate altitude, in radiative forcing neutralizing orders of magnitude more than its own mass in CO2)?

This is quite contrary to the warmists insistence that physics prove that the Earth MUST warm in the face of such an increase in radiative forcing.

«AIR TRAVEL» Data point: A 3,500 mile flight (such as from Los Angeles to Chicago, round trip) produces approximately 2,275 pounds of CO2e when accounting for radiative forcing.

In addition, the term pathway is meant to emphasize that it is not only a specific long - term concentration or radiative forcing outcome, such as a stabilization level, that is of interest, but also the trajectory that is taken over time to reach that outcome.

You seem to accept that the radiative effect of the added CO2 will emerge as the dominant climate change forcing, yet other human forcings, such as due to land use / land cover change are emerging as possibly larger effects.

And I'm not sure that there is such a consensus on the existence of radiative forcing or reemission.

So the 3.7 W m - 2 calculation for global radiative forcing could be refined perhaps by an improved experimental design (not necessarily by improved radiative transfer models) running RT models at each grid cell over the globe, over the diurnal cycle and the annual cycle for say 30 years, for the two different CO2 concentrations, such a detailed calculation would refine the 3.7 value.

Scientists keep track of natural forcings, but the observed warming of the planet over the second half of the 20th century can only be explained by adding in anthropogenic radiative forcings, namely increases in greenhouse gases such as carbon dioxide.

This is in particular relevant for scenario elements that are only indirectly coupled to the radiative forcing targets such as land use / land cover and air pollutant emissions.

BBD, As relieved as we are a devout «believer» such as yourself is finally stumbling towards a grasp of the basic principles of radiative physics etc, you need to now start thinking about joining the adult discussions on vastly less clear problems like the * size * of the AGW effect of AGW compared to natural forces, feedbacks etc..

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.»

This rate of increase in radiative forcing is often used in model intercomparison studies to assess general features of model response to such forcing.

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.

I find the lack of evidence for such simple things as CO2 radiative «forcing» in the temperature record to be apalling, considering how much undue weight it is given.

A positive radiative forcing involves shifting the balance such that the Earth gains heat and the climate warms.

Radiative forcing - Radiative forcing is the change in the net, downward minus upward, irradiance (expressed in W m - 2) at the tropopause due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide or the output of the Sun.

In principle, capturing carbon dioxide from the air (pdf of the Keith et al paper) and burying it in the ground could give you whatever radiative forcing you wanted; the limits to such a scheme are entirely economic, rather than being imposed on the earth system.

This includes radiative forcings such as a warming sun, cooling from sulfate aerosols or warming from CO2.

The radiative forcing of CO2 has such a plausible physical mechanism, as does the observed fact that absorbed solar energy tends to warm things up.

Thus such models can be used to help define the distribution of radiative constituents needed to calculate accurately the global climate forcing for alternative specifications of long - lived GHGs and surface albedo.

What literature are you relying on that has established such a delay in Earth's response to increased radiative forcings?

The strong relationship between peatland area and peat type with radiative forcing suggests a possible feedback for future changing climate, as high - latitude peatlands may experience prominent regime shifts, such as fen to bog transitions.

Additional output from the ACCMIP runs will include concentration / mass of radiatively active species, aerosol optical properties, and radiative forcings (clear and all sky) as well as important parameters that do not directly influence climate such as hydroxyl, chemical reaction rates, deposition rates, emission rates, surface pollutants and diagnostics of tracer transport.

Such a scaling of the land surface forcing provides a metric that can be expressed in the same units as radiative forcing.

Broadening the concept of radiative forcing in this way allows consideration of climate variables that may have more direct societal impacts, such as changes in precipitation.

Using a global climate model they show that the adjusted troposphere and stratosphere radiative forcing is consistent with the stratospheric adjusted forcing for more uniform forcings such as doubling CO2 and solar constant changes.

Well - known examples of such cases are the direct radiative forcing of black carbon (BC) and other absorbing aerosols and the changes in latent and sensible heat fluxes due to land - use modifications.

A growing number of studies perform both the chemical production, transformation, and transportation of aerosols and the radiative forcing calculations (see Chapter 5) with the advantage of correlating predicted aerosol distributions precisely with fields determining aerosol production and deposition such as clouds (e.g., Penner et al., 1998b).

As such, we find that recent global temperature records are consistent with the existing understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors with well known warming and cooling effects.

The probabilistic analyses of DAI reported in this section draw substantially on (subjective) Bayesian probabilities to describe key uncertainties in the climate system, such as climate sensitivity, the rate of oceanic heat uptake, current radiative forcing, and indirect aerosol forcing.

Decades of research by hundreds of independent scientific and academic institutions around the globe have discovered that human - caused climate change involves forcings such as the radiative forcing of well - mixed greenhouse gases, as well as land cover changes.