Sentences with phrase «radiative forcing caused»

This may suggest that for a given optical thickness, the influence of particle shape on the radiative forcing caused by a cloud composed of small ice crystals can be negligible.

The IPCC overstates the radiative forcing caused by increased CO2 concentration at least threefold because the models upon which it relies have been programmed fundamentally to misunderstand the difference between tropical and extra-tropical climates, and to apply global averages that lead to error.

This is one order of magnitude larger than the radiative forcing caused by the anthropogenic greenhouse gases (IPCC, 2001).

SGE deployment increases gradually over time and ends up being deployed at up to a 50 % intensity — that is, it offsets about one - half of the radiative forcing caused by anthropogenic greenhouse gas emissions.

The ISCCP - FD and ERBE data show cloud changes dominating over any possible change in radiative forcing caused by greenhouse gases.

The second study, led by Andrew Lacis, emphasizes the importance of the initial radiative forcing caused by CO2 and the other minor LLGHGs in sustaining the natural greenhouse effect and in causing changes in its magnitude.

The reason why I think it's wrong is that in her calculation of ESS she takes the radiative forcing caused by albedo changes (resulting from the massive change in ice coverage between a glacial and interglacial state) and assumes it to be a feedback on the CO2 induced temperature - change.

Aerosols have both natural and human sources, so if we just assume aerosol concentration variation in the atmosphere will continue as it has for the last 165 years, then future AGW can be projected with TCR (1 + beta) where beta is the historical fraction of CO2 radiative forcing caused by all other GHG and aerosols.

To describe the relative contribution of various GHG emissions to global warming, emissions were converted to CO2 equivalents, a metric that relates the radiative forcing caused by 1 mass unit of trace GHG to that caused by the emission of 1 mass unit of CO2 over a given time span.

A comparison of CO2 and CH4 fluxes from eutrophic reservoirs suggests that eutrophication does little to change the net carbon balance of reservoirs, but greatly increases the atmospheric radiative forcing caused by these systems through the stimulation of CH4 production (figure 3).

The largest uncertainty in the future radiative forcing caused by sea - ice loss is related to how clouds in the Arctic will change.

A simple method for estimating the global radiative forcing caused by the sea - ice - albedo feedback in the Arctic is presented.

Results show that the globally and annually averaged radiative forcing caused by the observed loss of sea ice in the Arctic between 1979 and 2007 is approximately 0.1 W m − 2; a complete removal of Arctic sea ice results in a forcing of about 0.7 W m − 2, while a more realistic ice - free - summer scenario (no ice for one month, decreased ice at all other times of the year) results in a forcing of about 0.3 W m − 2, similar to present - day anthropogenic forcing caused by halocarbons.

While concentrations of methane in the atmosphere are about 200 times lower than carbon dioxide, methane was responsible for 60 % of the equivalent radiative forcing caused by carbon dioxide since the onset of the Industrial Revolution.

Stefan is making a point on the change in radiative forcing caused by CO2 which is not the same as ECS.

Because there are overlaps — clouds alone could accomplish more; the presence of the gases reduces the additional radiative forcing caused by the addition of clouds.

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.

Are there some equivalent formulae for estimating the radiative forcing caused by water vapor feedback?

Are there some equivalent formulae for estimating the radiative forcing caused by water vapor feedback?

Thus, an estimate of climate sensitivity from past data requires an estimate of the magnitude of the past climate changes and of the radiative forcings causing the changes.

In figuring how much greater an impact radiative forcing causes, a radiative forcing index is used as a multiplier.

Not exact matches

A past study that Kravitz helped run at GeoMIP found that the abrupt termination of radiative forcing would cause global warming to effectively speed up to make up for all the time it lost, cramming five decades of warming into five or 10 years (ClimateWire, Nov. 27).

Forcing caused by changes in the Sun's brightness, by dust in the atmosphere, or by volcanic aerosols can also be translated into radiative fForcing caused by changes in the Sun's brightness, by dust in the atmosphere, or by volcanic aerosols can also be translated into radiative forcingforcing.

Suppose also that — DESPITE THIS STABILIZING MECHANISM some as - yet unknown ocean circulation cycle operates that is the sole cause of the Holocene centennial scale fluctuations, and that this cycle has reversed and is operating today, yielding a temperature change that happens to mimic what models give in response to radiative forcing changes.

Changes in TSI can be converted into a radiative forcing, which tells us the energy imbalance it causes on Earth.

This is a very straightforward and easy to understand formula - the larger the change in solar irradiance, the larger the energy imbalance it causes, and thus the larger the radiative forcing.

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.

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.»

The largest contribution to total radiative forcing is caused by the increase in the atmospheric concentration of CO2 since 1750.

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.»

It is the reduced amount of radiation leaving the top of the atmosphere that changes the earth's balance of heat, and therefore defines the «direct radiative forcing» caused by doubling CO2.

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.

This is about 0.03 Watt / m ^ 2 of Earth's surface while 2 x CO2 causes a radiative forcing of 3.7 Watt / m ^ 2.

Suppose also that — DESPITE THIS STABILIZING MECHANISM some as - yet unknown ocean circulation cycle operates that is the sole cause of the Holocene centennial scale fluctuations, and that this cycle has reversed and is operating today, yielding a temperature change that happens to mimic what models give in response to radiative forcing changes.

Overall, humans have caused an additional heating (radiative forcing) of 2.3 watts per square meter of Earth surface — as of 2011.

Starting from an old equilbrium, a change in radiative forcing results in a radiative imbalance, which results in energy accumulation or depletion, which causes a temperature response that approahes equilibrium when the remaining imbalance approaches zero — thus the equilibrium climatic response, in the global - time average (for a time period long enough to characterize the climatic state, including externally imposed cycles (day, year) and internal variability), causes an opposite change in radiative fluxes (via Planck function)(plus convective fluxes, etc, where they occur) equal in magnitude to the sum of the (externally) imposed forcing plus any «forcings» caused by non-Planck feedbacks (in particular, climate - dependent changes in optical properties, + etc.).)

The overall human - caused radiative forcing, which is given here as 1.6 watts per square meter, had already risen to 2.3 watts per square meter by the year 2011 according to the 5th IPCC report.

Fig. 1 Radiative forcing is the cause of global temperature changes.

Myhre, G. and A. Myhre, Uncertainties in radiative forcing due to surface albedo changes caused by land use changes, J. Climate, 16, 1511 - 1524, 2003.

The climate change hypothesis asserts that changes in radiative forcing resulting from increased greenhouse gas build up in the atmosphere increases GT and causes Atlantic SST to rise at least during the hurricane season months of August through October.

But the change in surface temperature would also cause a change in radiative forcing.

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.

Putting it all together, Figure 2 compares the warming from human caused greenhouse gases to the total radiative forcing from all human sources.

Radiative forcing has historically caused the warming of the seas, which has resulted in an unparalleled extension of drought in the state, according to a report from UCLA.

Trapp, R. J., N. S. Diffenbaugh, H. E. Brooks, M. E. Baldwin, E. D. Robinson, and J. S. Pal, 2007: Changes in severe thunderstorm environment frequency during the 21st century caused by anthropogenically enhanced global radiative forcing.

1) If we accept that the radiative forcing equations are correct and that a doubling of CO2 will cause an increase of 3.7 W / m2 and that will cause an increase in 1C we have to figure out what is the equation for normalizing this doubling of CO2 so as to get rid of the reference point Ex: doubling of CO2 from 1ppm to 2 ppm will not increase the temperature by 1C 2) Since 1980 mankind has increased fossil fuel burning by 75 % but CO2 in atmosphere has only increased 21 %.

So what empirical evidence is there that increasing Radiative Forcing long term on the Earth causes it to warm long term?

Therefore, our results confirm that positive radiative forcings (e.g., from human - caused increases in greenhouse gas concentrations) are necessary in order for the Earth to have warmed as much as it did over the 20th century.

The albedo change resulting from the snowline retreat on land is similarly large as the retreat of sea ice, so the combined impact could be well over 2 W / sq m. To put this in context, albedo changes in the Arctic alone could more than double the net radiative forcing resulting from the emissions caused by all people of the world, estimated by the IPCC to be 1.6 W / sq m in 2007 and 2.29 W / sq m in 2013.»

Humans cause numerous other radiative forcings, both positive (e.g. other greenhouse gases) and negative (e.g. sulfate aerosols which block sunlight).