Sentences with phrase «positive radiative forcing»

Moreover, there is a known positive radiative forcing.

Positive radiative forcing occurs when the Earth absorbs more energy from solar radiation than it emits as thermal radiation back to space.

A positive radiative forcing tends on average to warm the earth's surface; a negative radiative forcing on average tends to cool the earth's surface.

Radiative forcing is a measure of the change in boundary conditions, to which the climate system responds by either warming (in the case of positive radiative forcing; more energy coming in than going out) or cooling (negative radiative forcing).

absorbing aerosols, which lead to a positive radiative forcing of the troposphere with little net radiative effect at the top of the atmosphere;

Lateral expansion and carbon exchange of a boreal peatland in Finland resulting in 7000 years of positive radiative forcing.

The rate at which the Earth's climate warms in response to positive radiative forcing depends on several factors besides just the forcing.

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

The Earth reacts to positive radiative forcing by warming up until a new balance is achieved at a higher temperature.

Because the temperature is lower at higher altitudes, less energy is emitted, causing a positive radiative forcing.

The presence of BC resulted in positive radiative forcing in the atmosphere leading to warming effect (+ 2.1 W / m2) whereas cooling was observed at the top of the atmosphere (− 0.4 W / m2) and at surface (− 2.5 W / m2).

E.g. I would argue that even amidst the very large uncertainty, some trajectories are more likely than others (e.g. given a continued positive radiative forcing, warming is more likely than cooling).

Final Text: The headline message to this section states that human influence on the climate system is clear as it is evident from the increasing GHG concentrations in the atmosphere, positive radiative forcing, observed warming, and understanding of the climate system.

The relative proportion of the non-CO2 components of positive radiative forcing remains constant over time.

It points out that the greenhouse effect «paused» or exerted no positive radiative forcing on temperature (as expressed in W m - 2) from 1992 - 2014.

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).

/ /» This study indicates that the IPCC models are overpredicting global warming in response to positive 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-.

This is evident from the increasing greenhouse gas concentrations in the atmosphere, positive radiative forcing, observed warming, and understanding of the climate system.

(1) The Earth has been warming, implying a net positive radiative forcing.

(2) The largest positive radiative forcing — by far — has been the one due to long - lived greenhouse gases, most notably, CO2.

The reduced DMS emissions induce a significant positive radiative forcing of which 83 % (0.4 W / m2) can, in the model, be attributed to the impact of ocean acidification alone.

I am all for addressing CO2 and long - term change, but it makes no sense at all to be having continued positive radiative forcing from methane, for example, while we are waiting to get CO2 under control.

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.

Not exact matches

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).

First the radiative forcing of clouds is not just in the short wave, and depending on where they are, that can either be positive or negative.

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.

Total radiative forcing is positive, and has led to an uptake of energy by the climate system.

Gavin disputes that the main driver of the sea ice retreat is the albedo flip, but we are seeing not only polar amplification of global warming but positive feedback, which would not be explained simply by radiative forces and ocean currents.

(where the trend in net monochromatic flux reverses) before reaching the ultimate saturation; if this situation came up, after each «pseudosaturation», the radiative forcing can still be estimated with a band - widenning effect outside the central region where the last «pseudosaturation» has taken effect, minus the contribution from whatever is happenning in the center (think in terms of positive and negative areas on the graph).

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.

That's another blue on blue with regard to RealOldOne2's claims that changes in cloud are only a positive forcing with zero regard to the effect on radiative IR loss.

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).

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.

The radiative forcing is not the same thing as the radiative imbalance, and the numbers aren't at all comparable in this way, since the imbalance decays to zero as the planet gets warmer (even if positive or negative feedbacks dominate).

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

Fortunately, the negative and positive forcings are roughly equal and cancel each other out, and the natural forcings over the past half century have also been approximately zero (Meehl 2004), so the radiative forcing from CO2 alone gives us a good estimate as to how much we expect to see the Earth's surface temperature change.

The statement of Sato et al. «'' This suggests that estimates of the net negative radiative forcing due to the total ACI can also be significantly reduced and its uncertainty range could even include positive values.»

The authors give some hint when they write:» This suggests that estimates of the net negative radiative forcing due to the total ACI can also be significantly reduced and its uncertainty range could even include positive values.».

As a consequence, like the RFTP: INST, the stratosphere - adjusted radiative forcing at the TOA is positive over all of Antarctica and, in the model presented herein, surface temperatures increase everywhere over that continent in response to quadrupled CO2.

The IPCC diagram of radiative forcings is seriously in error, since it does not include any positive forcing for the removal of sulfate aerosols

These facts indicate that particulate matter from motor vehicles exerts a positive (i.e., warming) radiative climate forcing.

The second is that it rebutts Dessler 2010, who used a zero - lag regression of flux derivative for clear - sky and all - sky data, under a stated assumption of no significant radiative forcing component during the period 2000 to 2010, to conclude that cloud feedback really is positive.

Anomalies in the volcanic - aerosol induced global radiative heating distribution can force significant changes in atmospheric circulation, for example, perturbing the equator - to - pole heating gradient (Stenchikov et al., 2002; Ramaswamy et al., 2006a; see Section 9.2) and forcing a positive phase of the Arctic Oscillation that in turn causes a counterintuitive boreal winter warming at middle and high latitudes over Eurasia and North America (Perlwitz and Graf, 2001; Stenchikov et al., 2002, 2004, 2006; Shindell et al., 2003b, 2004; Perlwitz and Harnik, 2003; Rind et al., 2005; Miller et al., 2006).

-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).»

The CO2 can increase radiative forcing, the radiative forcing will increase the temperature of the oceans, this will draw out more CO2, and the positive feedback cycle will continue.

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

Most likely positive and negative feedbacks roughly cancel each other out, so that actual ECS is around 1.0 to 1.2, the value for the radiative forcing of CO2 by itself.

Radiative forcing can and is expected to create positive feedbacks that will amplify global warming in a non-linear accelerating progression.

The forcing by lower stratospheric O3 is an unusual one in that it has a positive short - wave and a negative long - wave radiative forcing.