Sentences with phrase «anthropogenic radiative»

Although the anthropogenic radiative forcing of 2.4 W / m2 [IPCC 2001] is small compared to the natural one, it is of major importance to the future trend of Earth's climate.

«The land — sea warming ratio in the ECHAM — HadISST holds also for the warming trend over the most recent decades, despite the fact that no anthropogenic radiative forcings are included in the simulations.

It is straightforward to argue that a climate with significant internal variability is a climate that is very sensitive to applied anthropogenic radiative anomalies [cf. Roe, 2009].

It is straightforward to argue that a climate with significant internal variability is a climate that is very sensitive to applied anthropogenic radiative anomalies (c.f. Roe [2009]-RRB-.

However, the use of this term is not uniform when discussing stabilisation targets as some authors define carbon dioxide equivalent concentrations as the net forcing of all anthropogenic radiative forcing agents including greenhouse gases, tropospheric ozone, and aerosols but not natural forcings.

The net anthropogenic radiative forcing and its range are also shown.

non-CO2 climate forcing agents, which together are estimated to be as much as 40 — 50 % of positive anthropogenic radiative forcing

«In summary, our results emphasize the significant role of remote oceanic influences, rather than the direct local effect of anthropogenic radiative forcings, in the recent continental warming.

Methane is an important part of the anthropogenic radiative forcing Methane emissions have a direct GHG effect, and they effect atmospheric chemistry and stratospheric water vapour which have additional impacts natural feedbacks involving methane likely to be important in future — via wetland response to temperature / rain change, atmospheric chemistry and, yes, arctic sources There are large stores of carbon in the Arctic, some stored as hydrates, some potentially convertible to CH4 by anaerobic resporation [from wikianswers: Without oxygen.

Therefore, the net anthropogenic radiative forcing thus far is between approximately 0 % and 58 % of the forcing associated with a doubling of atmospheric CO2, with a most likely value of 30 %.

-LSB-...] With the increase in irradiance and a decline in explosive volcanism in the early 20th century, global temperatures might then have returned to an unperturbed level similar to that of the MQP [Medieval Quiet Period], but the rapid rise in anthropogenic greenhouse gases propelled temperatures well beyond that level, as positive anthropogenic radiative forcing overwhelmed natural variability (Myhre et al., 2013).»

Even if the anthropogenic radiative forcing was better known, it is theoretically unclear by how much the temperature should have varied in response.

By your 7 % reference, are you referring to the percentage solar irradiance is of total anthropogenic radiative forcing?

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.

Anthropogenic radiative forcing exploded after 1950.

Alternatively, the IPCC anthropogenic radiative forcings and / or the solar radiative forcing could be in error.

«Please explain, for instance, in which way the tropopause region for which the so - called anthropogenic radiative forcing was estimated can warm the earth's surface which has a temperature of about 65 K higher than the tropopause region.

do you believe that the tropopause region for which the anthropogenic radiative forcing is calculated can warm the nearly 65 K warmer Earth's surface without any compensating changes?

More comprehensive analyses also show total anthropogenic radiative forcings increasing dramatically after 1950.

In addition, since IPCC tells us that the total net anthropogenic radiative forcing is essentially equal to the radiative forcing from CO2 alone, we can essentially ignore other anthropogenic forcing factors (positive and negative).

Instead, I've repeatedly pointed out that it's unphysical to assume that anthropogenic radiative forcings are the same before and after 1950.

Under most scenarios of late 20th century and future anthropogenic radiative forcing, a steady, rather than accelerating, rise in global and hemispheric mean temperature is predicted over timescales of decades.

wilt, the paper you cite describes what in their view is a «small but statistically significant effect of cosmic rays on cloud formation, which in no way invalidates the large and significant effects of human emissions on the current anthropogenic radiative forcing budget of the atmosphere.

Precisely how ENSO will respond to anthropogenic radiative forcing is still an area of active debate within the climate research community.

The model results (which are based on driving various climate models with estimated solar, volcanic, and anthropogenic radiative forcing changes over this timeframe) are, by in large, remarkably consistent with the reconstructions, taking into account the statistical uncertainties.

The recent decadal slowdown... is unique in having occurred during a time of strongly increasing anthropogenic radiative forcing of the climate system.

Not exact matches

The radiative properties of water vapour are accounted for in all the models used in the IPCC reports which attribute a significant portion of recent warming to anthropogenic effects.

While a relatively minor part of the overall aerosol mass, changes in the anthropogenic portion of aerosols since 1750 have resulted in a globally averaged net radiative forcing of roughly -1.2 W / m2, in comparison to the overall average CO2 forcing of +1.66 W / m2.

The mechanism for reducing anthropogenic global warming, initiated through radiative forcing of greenhouse gases, is to stop emissions and reduce their concentration in the atmosphere to levels which do not stimulate carbon feedbacks.

Gregory et al. (2002) used observed interior - ocean temperature changes, surface temperature changes measured since 1860, and estimates of anthropogenic and natural radiative forcing of the climate system to estimate its climate sensitivity.

Let's set the stage by noting that, as a significant competitor to anthropogenic greenhouse forcing of recent climate change, the direct radiative forcing by solar irradiance variations is dead on arrival.

However, Section 2.9 updates the Boucher and Haywood analysis for current radiative forcing estimates since 1750 and shows that it is extemely likely that the combined anthropogenic RF is both positive and substantial (best estimate: +1.6 W m — 2).

Your earlier # 182 was equally disconcerting where you quoted Norris and Slingo (2009) saying «At present, it is not known whether changes in cloudiness will exacerbate, mitigate, or have little effect on the increasing global surface temperature caused by anthropogenic greenhouse radiative forcing.»

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-.

Consequently, as they say slightly earlier in the abstract: «At present, it is not known whether changes in cloudiness will exacerbate, mitigate, or have little effect on the increasing global surface temperature caused by anthropogenic greenhouse radiative forcing.»

This mostly reflects the response to global radiative forcings, which are dominated by anthropogenic forcing over the 20th Century.

Can any of the experts lurking here refer me to any updates to the anthropogenic direct effect aerosol radiative forcing digram — Figure 6.8 -(Figure 401) in the TAR?

But models based on physical principles also reproduce the response to seasonal and spatial changes in radiative forcing fairly well, which is one of the many lines of evidence that supports their use in their prediction of the response to anthropogenic forcing.

Summary for Policymakers Chapter 1: Introduction Chapter 2: Observations: Atmosphere and Surface Chapter 3: Observations: Ocean Chapter 4: Observations: Cryosphere Chapter 5: Information from Paleoclimate Archives Chapter 6: Carbon and Other Biogeochemical Cycles Chapter 7: Clouds and Aerosols Chapter 8: Anthropogenic and Natural Radiative Forcing Chapter 8 Supplement Chapter 9: Evaluation of Climate Models Chapter 10: Detection and Attribution of Climate Change: from Global to Regional Chapter 11: Near - term Climate Change: Projections and Predictability Chapter 12: Long - term Climate Change: Projections, Commitments and Irreversibility Chapter 13: Sea Level Change Chapter 14: Climate Phenomena and their Relevance for Future Regional Climate Change Chapter 14 Supplement Technical Summary

Geophysical Fluid Dynamics Laboratory general circulation model investigation of the indirect radiative effects of anthropogenic sulfate aerosol Journal of Geophysical Resarach, 2005

Currently, although only 20 % of the accumulated anthropogenic rise in carbon dioxide originates from land use and land cover change (LULCC), 40 % of the net positive radiative forcing from human activities is attributable to LULCC sources (Ward et al 2014).

As we have discussed several times elsewhere on this site, studies employing model simulations of the past millennium have been extremely successful in reproducing many of the details evident in paleoclimate reconstructions of this interval as a forced response of the climate to natural (primarly volcanic and solar) and in more recent centuries, anthropogenic, radiative changes.

It presents a significant reinterpretation of the region's recent climate change origins, showing that atmospheric conditions have changed substantially over the last century, that these changes are not likely related to historical anthropogenic and natural radiative forcing, and that dynamical mechanisms of interannual and multidecadal temperature variability can also apply to observed century - long trends.

Note too that this would only be a small increase in radiative forcing — less than the sustained anthropogenic increase in methane we have already seen.

The NCAR CSM 1.4 was driven by the radiative forcings (volcanic + solar natural and anthropogenic ghg + aerosol) developed in Ammann et al (2007).

And note that for this to be as important as the radiative forcing associated with anthropogenic CO2, you'd still need to multiply it by 20.

This is about twice the radiative forcing today from all anthropogenic greenhouse gases today, or (again according to Modtran) it would translate to an equivalent CO2 at today's methane concentration of about 750 ppm.

This increase is more than double the IPCC's estimated radiative forcing from all anthropogenic emissions of greenhouse gases.

It is virtually certain that anthropogenic aerosols produce a net negative radiative forcing (cooling influence) with a greater magnitude in the NH than in the SH.

Unlike the scenarios developed by the IPCC and reported in Nakicenovic et al. (2000), which examined possible global futures and associated greenhouse - related emissions in the absence of measures designed to limit anthropogenic climate change, RCP4.5 is a stabilization scenario and assumes that climate policies, in this instance the introduction of a set of global greenhouse gas emissions prices, are invoked to achieve the goal of limiting emissions and radiative forcing.