Sentences with phrase «between radiative forcing»

Given the supposed logarithmic relationship between radiative forcing and climate sensitivity, even 15.45 oC for GISStemp when CO2 has doubled seems an over-estimate.

Many details have certainly some influence on the relationship between radiative forcing at the TOA (or tropopause) and the average temperature of the earth surface.

Blowers et al. (10) have examined the GWPs of hydrofluoroethers (HFEs) and noted that their radiative forcing values increase with an increasing number of C ─ F bonds, but they assert a linear relationship between the radiative forcing and the number of C ─ F bonds, rather than the more complicated, nonlinear relationship found in our study.

Even between use and temperature there is a correlation, and between radiative forcing and temperature (the more appropriate comparison) the correlation is stronger.

The relation between radiative forcing and temperature: What do statistical analyses of the observational record measure?

Houghton (2004: 259) explains that when converting from carbon dioxide only concentrations to carbon dioxide equivalent concentrations, the amount that needs to be added varies with different concentrations of greenhouse gases as the relationship between radiative forcing and concentration is non-linear.

It is concluded that atmospheric feedback diagnosis of the climate system remains an unsolved problem, due primarily to the inability to distinguish between radiative forcing and radiative feedback in satellite radiative budget observations.

The results confirm that cointegration between radiative forcing and temperatures are consis - tent with the data.

This paper re-examines the relationship between radiative forcing and temperatures from a structural time series modelling perspective.

Even if adjustments are required (not likely), this would have no real impact on the well quantified relationship between radiative forcing from greenhouse gases and increasing global temperatures.

Reliable data on decadal variability of the Earth's radiation budget are hard to come by, but to provide some reality check I based my setting of the scaling factor between radiative forcing and the SOI / PDOI index on the tropical data of Wielecki et al 2002 (as corrected in response to Trenberth's criticism here.)

For one thing, the energy balance between radiative forcing and temperature response gives a non-linear relation between the forcing, F, and temperature to the fourth power, T4 (the Stefan - Boltzmann law).

Not exact matches

The researchers [3] quantified China's current contribution to global «radiative forcing» (the imbalance, of human origin, of our planet's radiation budget), by differentiating between the contributions of long - life greenhouse gases, the ozone and its precursors, as well as aerosols.

They, too, assume an equivalence in radiative forcing between GHG and aerosol, What they do is add different estimates of the aerosol radiative forcing to the GHG forcing, while keeping the temperature response fixed at the observed recent warming.

In addition, researchers calculated the changes in the shortwave and longwave and net radiation between the pre-industrial simulation and the present - day simulations to estimate the radiative forcing resulting from the aerosol effects on cirrus clouds.

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.

We note, however, that Mount Pinatubo does not provide a perfect proxy for global warming, because the nature of the external radiative forcing obviously differs between the two.

«We use a massive ensemble of the Bern2.5 D climate model of intermediate complexity, driven by bottom - up estimates of historic radiative forcing F, and constrained by a set of observations of the surface warming T since 1850 and heat uptake Q since the 1950s... Between 1850 and 2010, the climate system accumulated a total net forcing energy of 140 x 1022 J with a 5 - 95 % uncertainty range of 95 - 197 x 1022 J, corresponding to an average net radiative forcing of roughly 0.54 (0.36 - 0.76) Wm - 2.»

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).

For comparison, the corresponding radiative forcing in the most recent IPCC report, however, ranges between +0.38 and +0.68 W / m2

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-.

On the possibility of a changing cloud cover «forcing» global warming in recent times (assuming we can just ignore the CO2 physics and current literature on feedbacks, since I don't see a contradiction between an internal radiative forcing and positive feedbacks), one would have to explain a few things, like why the diurnal temperature gradient would decrease with a planet being warmed by decreased albedo... why the stratosphere should cool... why winters should warm faster than summers... essentially the same questions that come with the cosmic ray hypothesis.

The difference in TSI between Shapiro et al and most other recent reconstructions (between Maunder minimum and the present) is about a factor of 10, but the difference in radiative forcing as quoted in this post (see the paragraph below) is only a factor of 2.

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).

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.

[Radiative forcing is the amount of imbalance between energy reaching the Earth and radiating into space.]

Dr. Swanson: One distinction between your analysis and the more conventional ones is the rate of underlying warming that is occurring due to radiative forcings.

Berntsen at al used statistics to investigate the relationship between global temperatures and changes in radiative forcing.

The only way this relationship could be linear would be if an increase in airborne fraction cancels out the logarithmic relationship between CO2 concentrations and radiative forcing.

The effect is a continuum of different absorption spectra that all have the same band - widenning per doubling and same effects at the center at various stages between no effect and saturation, though they are at different stages in that process for any given amount of CO2; the radiative forcing is a weighted average of the effects of each of those absorption spectra; once the center of the band is saturated for all of the spectra, the band widenning effect is the same for each and thus the forcing from the band widenning is the same as it is in the original simplified picture.

The variation of RF over a layer, increasing / decreasing with height, means that there is a forced convergence / divergence of radiative fluxes; the RF acting on a layer is equal to the difference between RF at the top and bottom of the layer and is positive / negative if the RF is greater / smaller at the top.

They, too, assume an equivalence in radiative forcing between GHG and aerosol, What they do is add different estimates of the aerosol radiative forcing to the GHG forcing, while keeping the temperature response fixed at the observed recent warming.

The difference in radiant flux will be smaller between 222 K and 255 K, and larger between 288 K and 321 K, and it will take a greater GHE TOA forcing to reduce the effective radiating temperature (the temperature of a blackbody that would emit a radiative flux) at TOA from 288 K to 277 K as it would to reduce it from 277 K to 266 K, etc..

As discussed by Veizer et al. there is a major discrepancy during the mid-Mesozoic (120 to 220 Ma) between cold low - latitude temperatures deduced from the oxygen isotopic composition (λ 18O) of fossils and high levels of CO2 and net radiative forcing.

Then the records discussed above would show a reduced amplitude cycle, but a strong correlation between CO2 radiative forcing and temperature.

It is determined by the covariance between the temperature history and the estimated radiative forcing.

Using the modtran model on line I get a radiative forcing from 10 * atmospheric methane of 3.4 Watts / m2 (the difference in the instantaneous IR flux out, labeled Iout, between cases with and without 10x methane).

And now we're going to see a metaphorical shootout, on the high ground of twenty - first - century atmospheric physics, between the likes of Inhofe - Barton - Boehner - Sensenbrenner & Co. and Hansen - Schmidt - Lacis - Chu - Holdren - Karl etc. on the issue of the radiative forcing due to greenhouse gases?

See Stowasser & Hamilton, Relationship between Shortwave Cloud Radiative Forcing and Local Meteorological Variables Compared in Observations and Several Global Climate Models, Journal of Climate 2006; Lauer et al., The Impact of Global Warming on Marine Boundary Layer Clouds over the Eastern Pacific — A Regional Model Study, Journal of Climate 2010.

This difference between simulated and observed trends could be caused by some combination of (a) internal climate variability, (b) missing or incorrect radiative forcing and (c) model response error.

The imbalance between the absorbed and emitted radiation that results from these changes will be referred to here as «climate forcing» (sometimes known as «radiative forcing») and given in units of Wm - 2.

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.

Or one can take the more sane position that distribution of radiative forcing does matter and this explains a fair amount of the discrepancy between instrumental estimates and paleoclimate estimates.

The relationship between the modelled radiative forcing for the year 2000 and the estimates derived in Chapter 2 is evaluated in Section 10.2.1.3.

The manuscript uses a simple energy budget equation (as employed e.g. by Gregory et al 2004, 2008, Otto et al 2013) to test the consistency between three recent «assessments» of radiative forcing and climate sensitivity (not really equilibrium climate sensitivity in the case of observational studies).

Well it would have to be immune to a temperature rise due to a uniform forcing, which could be satisfied if the induced forcing (radiative) was proportionate to a positive temperature difference between an initiating region (where the internal forcing would take place) and a responding region.

He then examined several possible sources of compensation between climate sensitivity and radiative forcing.

Observational determination of surface radiative forcing by CO2 from 2000 to 2010 «Here we present observationally based evidence of clear - sky CO2 surface radiative forcing that is directly attributable to the increase, between 2000 and 2010, of 22 parts per million atmospheric CO2.»