Sentences with phrase «on changes in albedo»

Not exact matches

The impact of grain size on albedo — the ratio between reflected and incoming solar radiation — is strong in the infrared range, where humans can't see, but satellite instruments can detect the change.

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

You've hit on one of the weaknesses of the paper, as the model they use admittedly doesn't model changes in albedo (at least, not as a model output).

eg how big is the «expected» impact on the climate / temps etc from that kind of change / feedback in ASI albedo

An increase in greenhouse absorbers or a change in the albedo have analogous impacts on the TOA balance.

Other factors would include: — albedo shifts (both from ice > water, and from increased biological activity, and from edge melt revealing more land, and from more old dust coming to the surface...); — direct effect of CO2 on ice (the former weakens the latter); — increasing, and increasingly warm, rain fall on ice; — «stuck» weather systems bringing more and more warm tropical air ever further toward the poles; — melting of sea ice shelf increasing mobility of glaciers; — sea water getting under parts of the ice sheets where the base is below sea level; — melt water lubricating the ice sheet base; — changes in ocean currents -LRB-?)

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

Perhaps you might want to read that paper as well as «Climate Change and Trace Gases», available in many places, which argues for an albedo flip mechanism and (relatively) short timescales for icesheet response to forcing, based on paleo data.

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 hypothesiOn 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 hypothesion 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.

«Soot snow / ice albedo climate forcing is not included in Intergovernmental Panel on Climate Change evaluations.

(In the full 4 - dimensional climate, responses can also tend spread horizontally by convection (advection) and temporally by heat capacity, though «fingerprints» of horizontal and temporal variations in RF (externally imposed and feedback — snow and ice albedo, for example) can remain — this spreading is somewhat different as it relies in part on the circulation already present as well as circulation changeIn the full 4 - dimensional climate, responses can also tend spread horizontally by convection (advection) and temporally by heat capacity, though «fingerprints» of horizontal and temporal variations in RF (externally imposed and feedback — snow and ice albedo, for example) can remain — this spreading is somewhat different as it relies in part on the circulation already present as well as circulation changein RF (externally imposed and feedback — snow and ice albedo, for example) can remain — this spreading is somewhat different as it relies in part on the circulation already present as well as circulation changein part on the circulation already present as well as circulation changes)

The rise of CO2 from 270ppm to now over 400ppm, the extent of equatorial and sub tropical deforestation, the soot deposits on the polar ice caps, the increase in atmospheric water vapour due to a corresponding increase in ocean temps and changes in ocean currents, the extreme ice albedo currently happening in the arctic etc, etc are all conspiring in tandem to alter the climate as we know it.

Improvements in the capacity to monitor direct and indirect changes on weather, climate, or larger Earth systems and to detect unilateral or uncoordinated deployment could help further understanding of albedo modification and climate science generally.

It is not that the polar regions are amplifying the warming «going on» at lower latitudes, it is that any warming going on AT THE POLES is amplified through inherent positive feedback processes AT THE POLES, and specifically this is primarily the ice - albedo positive feedback process whereby more open water leads to more warming leads to more open water, etc. *** «Climate model simulations have shown that ice albedo feedbacks associated with variations in snow and sea - ice coverage are a key factor in positive feedback mechanisms which amplify climate change at high northern latitudes...»

Thus, the positive λSW of the CMIP5 ensemble average and the resulting energy accumulation by enhanced ASR under GHG forcing can be expected based only on the robust physics of the water vapor feedback and the surface albedo feedback in the absence of any changes in clouds... ``

At best, maybe jetfuel would be on to something if the change in seasonal ice / snow cover in Canada is measurably altering the albedo, as scaddenp notes, but I doubt we'll see jetfuel come up with any evidence showing the existence or magnitude of such an effect.

In models that include indirect effects, different treatments of the indirect effect are used, including changing the albedo of clouds according to an off - line calculation (e.g., Tett et al., 2002) and a fully interactive treatment of the effects of aerosols on clouds (e.g., Stott et al., 2006b).

Taken into account with increase in the amount of insolation by reducing particulates, albedo changes, and so on, a couple of K or so might be reasonable.

However, even a smaller figure (I had calculated about 0.17 W / m ^ 2 based on your inflated figure for total planetary albedo, but you can check it out) is still significant when compared with the total flux imbalance, which I think is a more informative comparison than an arbitrarily selected change in cloud cover, because it compares the sea ice reduction with the effects of all climate variations that have been operating in recent years..

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.»

Based on evidence from Earth's history, we suggest here that the relevant form of climate sensitivity in the Anthropocene (e.g. from which to base future greenhouse gas (GHG) stabilization targets) is the Earth system sensitivity including fast feedbacks from changes in water vapour, natural aerosols, clouds and sea ice, slower surface albedo feedbacks from changes in continental ice sheets and vegetation, and climate — GHG feedbacks from changes in natural (land and ocean) carbon sinks.

Isostatic rebound in response to glacier retreat (unloading), increase in local salinity (i.e., δ18Osw), have been attributed to increased volcanic activity at the onset of Bølling — Allerød, are associated with the interval of intense volcanic activity, hinting at a interaction between climate and volcanism - enhanced short - term melting of glaciers, possibly via albedo changes from particle fallout on glacier surfaces.

Urban heat island - The relative warmth of a city compared with surrounding rural areas, associated with changes in runoff, the concrete jungle effects on heat retention, changes in surface albedo, changes in pollution and aerosols, and so on.

The degree of inconsistency, however, is difficult to ascertain without information on possible changes in low - level cloud albedo.»

The identified atmospheric feedbacks including changes in planetary albedo, in water vapour distribution and in meridional latent heat transport are all poorly represented in zonal energy balance model as the one used in [7] whereas they appear to be of primary importance when focusing on ancient greenhouse climates.

AGW climate scientists seem to ignore that while the earth's surface may be warming, our atmosphere above 10,000 ft. above MSL is a refrigerator that can take water vapor scavenged from the vast oceans on earth (which are also a formidable heat sink), lift it to cold zones in the atmosphere by convective physical processes, chill it (removing vast amounts of heat from the atmosphere) or freeze it, (removing even more vast amounts of heat from the atmosphere) drop it on land and oceans as rain, sleet or snow, moisturizing and cooling the soil, cooling the oceans and building polar ice caps and even more importantly, increasing the albedo of the earth, with a critical negative feedback determining how much of the sun's energy is reflected back into space, changing the moment of inertia of the earth by removing water mass from equatorial latitudes and transporting this water vapor mass to the poles, reducing the earth's spin axis moment of inertia and speeding up its spin rate, etc..

To date, while various effects and feedbacks constrain the certainty placed on recent and projected climate change (EG, albedo change, the response of water vapour, various future emissions scenarios etc), it is virtually certain that CO2 increases from human industry have reversed and will continue to reverse the downward trend in global temperatures that should be expected in the current phase of the Milankovitch cycle.

Broad - scale changes in vegetation in general, and tree loss in particular, have pronounced effects on climate processes through biogeophysical mechanisms such as albedo, evapotranspiration (ET), and carbon dioxide exchange with the atmosphere [11].

«They believe changes in albedo should be an important part of future studies on atmosphere and climate change.»

Ibid., pp. 393 — 96; Yun Qian et al., «Effects of Soot - Induced Snow Albedo Change on Snowpack and Hydrological Cycle in Western United States Based on Weather Research and Forecasting Chemistry and Regional Climate Simulations,» Journal of Geophysical Research, vol.

Earlier this year he and others pinpointed a change in albedo — a measure of the reflectivity of snow on the island — that suggested that melting might accelerate.

He'd been studying changes in Greenland's albedo (the scientific term for the reflectivity of ice), but hadn't focused on the role of black carbon.

The only thing that I would contend could be added would be long slow cumulative changes in solar output other than raw TSI namely changes in the mix of particles and wavelengths over longer periods of time such as MWP to LIA to date and which seem to have some effect on surface pressure distribution and global albedo so as to alter solar shortwave into the oceans and thus affecting the energy available to the ENSO process.

25 Uncertainties Changes in atmospheric water vapor — Changes in cloudiness — Changes in albedo Carbon budgets Aerosol particles — Direct effects — Impact on clouds — Black carbon

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.

1) In reality both the changes in albedo (reflectivity) and CO2 concentration are feedbacks on the orbital forcing, and the relation in the one direction (a change in earth's orbit causing a temperature change which in turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COIn reality both the changes in albedo (reflectivity) and CO2 concentration are feedbacks on the orbital forcing, and the relation in the one direction (a change in earth's orbit causing a temperature change which in turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COin albedo (reflectivity) and CO2 concentration are feedbacks on the orbital forcing, and the relation in the one direction (a change in earth's orbit causing a temperature change which in turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COin the one direction (a change in earth's orbit causing a temperature change which in turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COin earth's orbit causing a temperature change which in turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COin turn causes albedo and CO2 levels to change) is not necessarily the same as the relation in the reverse direction, as is currently happening with human - induced increases in COin the reverse direction, as is currently happening with human - induced increases in COin CO2.

Based on the understanding of both the physical processes that control key climate feedbacks (see Section 8.6.3), and also the origin of inter-model differences in the simulation of feedbacks (see Section 8.6.2), the following climate characteristics appear to be particularly important: (i) for the water vapour and lapse rate feedbacks, the response of upper - tropospheric RH and lapse rate to interannual or decadal changes in climate; (ii) for cloud feedbacks, the response of boundary - layer clouds and anvil clouds to a change in surface or atmospheric conditions and the change in cloud radiative properties associated with a change in extratropical synoptic weather systems; (iii) for snow albedo feedbacks, the relationship between surface air temperature and snow melt over northern land areas during spring and (iv) for sea ice feedbacks, the simulation of sea ice thickness.

From what I understand it's deltaT (of GMT) that works on clouds and water vapor (let's dismiss ice albedo because it more polar «less aggregate») to create changes which in turn positively increment deltaT.

Apologies if this has already been stated, but my view on decreased Arctic ice cover is: - 1, as Judith pointed out, when ice is at a minimum the sun is already so low in the sky that there is no noticeable change to albedo, 2 when there is ice cover warm water is kept at depth by differences in salinity, When there is open water, storms mix the haline layers bringing warm water to the surface where it can more readily radiate it's energy into outer space.

Thus if the two mid latitude jets move equatorward at the same time as the ITCZ moves closer to the equator the combined effect on global albedo and the amount of solar energy able to penetrate the oceans will be substantial and would dwarf the other proposed effects on albedo from changes in cosmic ray intensity generating changes in cloud totals as per Svensmark and from suggested changes caused in upper cloud quantities by changes in atmospheric chemistry involving ozone which various other climate sceptics propose.

That's a pretty silly claim on Dr. Curry's part if you consider that in the months the arctic sea ice isn't diminished, there's never really so much sunlight as you'd count it against the average, so whatever albedo changes there are during the half of the year that matters, they're when the sun is at its highest angle.

Read more: Stanford University Aerosols Also Implicated in Glacier Melting, Changing Weather Patterns Other research examining the effects of soot on melting glaciers and changing weather pattens in South Asia has reached similar conclusions: Beyond increasing atmospheric warming, because the soot coats the surface of the snow and ice it changes the albedo of the surface, allowing it to absorb more sunlight and thereby accelerating Changing Weather Patterns Other research examining the effects of soot on melting glaciers and changing weather pattens in South Asia has reached similar conclusions: Beyond increasing atmospheric warming, because the soot coats the surface of the snow and ice it changes the albedo of the surface, allowing it to absorb more sunlight and thereby accelerating changing weather pattens in South Asia has reached similar conclusions: Beyond increasing atmospheric warming, because the soot coats the surface of the snow and ice it changes the albedo of the surface, allowing it to absorb more sunlight and thereby accelerating melting.

I recall one post on how Earth came out of a snowball, which explanation may be a possibility but then again there may be other explanations (eg., oceanic volcanos splitting in the ice and thereby releasing some water vapour, soot deposits changing albedo, even meteor collision — who knows given the lack of evidence).

Back to Jim: when I first arrived here I believed in AGW based on the papers and books you guys in climate science cite and publish yourselves: more IFR trapping, changing albedo, positive feedbacks, increased W2 forcing, etc..

However, climate mitigation policies do not generally incorporate the effects of these changes in the land surface on the surface albedo, the fluxes of sensible and latent heat to the atmosphere, and the distribution of energy within the climate system.

However, there are also changes in the albedo of snow due to growth of biological communities based on algae when nutrients are deposited on snow.

Seems to me David's mistake is not noticing that the rapid events are internal to the climate system, not external; they may cause fast changes in albedo for example for a while; and they are modeled, see Dr. Bitz's work on Arctic sea ice, or any model including volcanos or Atlantic deep water currents etc..

The impact of tree planting in previously unforested areas can be paradoxical, as it depends both on seasonal changes in surface albedo, eg, from snowfall and sun angle a and shadow area effects.

Paper: Reference: Yun Qian, William I. Gustafson Jr., L. Ruby Leung, Steven J. Ghan, Effects of soot - induced snow albedo change on snowpack and hydrological cycle in western U.S. based on WRF chemistry and regional climate simulations, Journal of Geophysical Research - Atmospheres, 2009, doi: 10.1029 / 2008JD011039

In the almost sure knowledge that the earth never experienced a runaway greenhouse even with ancient CO2 levels 10 to 20 times greater than today, these anti-science scoundrels insist with a «high level of confidence» that this amplification is real and it's based on nothing more than faster than expected surface temperature rise in the past few decades which can be TOTALLY explained by multi-decadal cyclic behavior in ocean currents, trade winds, and / or solar magnetic activity causing small global average albedo changeIn the almost sure knowledge that the earth never experienced a runaway greenhouse even with ancient CO2 levels 10 to 20 times greater than today, these anti-science scoundrels insist with a «high level of confidence» that this amplification is real and it's based on nothing more than faster than expected surface temperature rise in the past few decades which can be TOTALLY explained by multi-decadal cyclic behavior in ocean currents, trade winds, and / or solar magnetic activity causing small global average albedo changein the past few decades which can be TOTALLY explained by multi-decadal cyclic behavior in ocean currents, trade winds, and / or solar magnetic activity causing small global average albedo changein ocean currents, trade winds, and / or solar magnetic activity causing small global average albedo changes.