A team from Fukushima University recently mapped radiation levels at 370 spots in the prefecture and, using weather balloons, confirmed that
atmospheric radiation levels have dropped to near background levels.
Not exact matches
«Despite stronger solar wind and EUV -
radiation levels under the early Sun, ion escape can not explain more than 0.006 bar of
atmospheric pressure lost over the course of 3.9 billion years,» says Robin Ramstad.
At sea
level on Earth, sunlight's «
radiation pressure» is about 50 million times smaller than
atmospheric pressure.
The whole issue is that any
level above what is often called the «effective radiating
level» (say, at ~ 255 K on Earth) should start to cool as
atmospheric CO2 increases, since the layers above this height are being shielded more strongly from upwelling
radiation... except not quite, because convection distributes heating higher than this
level, the stratosphere marks the point where convection gives out and there is high static stability.
As the
atmospheric opacity is increased (e.g., 2xCO2), the physical location of the TAU = 1
level will rise to a higher altitude, but the outgoing flux will still come from the TAU = 1
level since
radiation doesn't care about the geometric scale), and the TAU = 1
level will still correspond to the same temperature (since the solar input energy is unchanged).
Increased
atmospheric CO2 tends to close this window and cause outgoing
radiation to emerge from higher, colder
levels, thus warming the surface and lower atmosphere by the so called greenhouse mechanism»
The cryosphere derives its importance to the climate system from a variety of effects, including its high reflectivity (albedo) for solar
radiation, its low thermal conductivity, its large thermal inertia, its potential for affecting ocean circulation (through exchange of freshwater and heat) and
atmospheric circulation (through topographic changes), its large potential for affecting sea
level (through growth and melt of land ice), and its potential for affecting greenhouse gases (through changes in permafrost)(Chapter 4).
Daily mean NCEP / NCAR reanalysis data are used as
atmospheric forcing, i.e., 10 - m surface winds, 2 - m surface air temperature (SAT), specific humidity, precipitation, evaporation, downwelling longwave
radiation, sea
level pressure, and cloud fraction.
Even though
radiation from the troposphere is much slower, the heat is much more widely distributed; a lot of it is moved over what would have been much cooler ground — it isn't just low
level atmospheric heat transport that matters.
Yet on these sites (and in the media, and even by a few semi related scientists who kinda keep an eye on the issue or are semi involved) treat it as if it is some sort of both immediate, and linear, contemporaneous correlation between increased lower
level atmospheric re
radiation, and increased (or changed) global ambient air temperatures, which is absurd, and belies any real deep understanding of the actual issue.
Since to me (and many scientists, although some wanted a lot more corroborative evidence, which they've also gotten) it makes absolutely no sense to presume that the earth would just go about its merry way and keep the climate nice and relatively stable for us (though this rare actual climate scientist pseudo skeptic seems to think it would, based upon some non scientific belief — see second half of this piece), when the earth changes climate easily as it is, climate is ultimately an expression of energy, it is stabilized (right now) by the oceans and ice sheets, and increasing the number of long term thermal
radiation / heat energy absorbing and re radiating molecules to
levels not seen on earth in several million years would add an enormous influx of energy to the lower atmosphere earth system, which would mildly warm the air and increasingly transfer energy to the earth over time, which in turn would start to alter those stabilizing systems (and which, with increasing ocean energy retention and accelerating polar ice sheet melting at both ends of the globe, is exactly what we've been seeing) and start to reinforce the same process until a new stases would be reached well after the
atmospheric levels of ghg has stabilized.
While actual scientists are trying to piece together every little part of an otherwise almost un-piecable long term chaotic and variable system in response now to a massive increase in net lower
atmospheric energy absorption and re
radiation, Curry is busy — much like most of the comments on this site most of the time — trying to come up with or re-post every possible argument under the sun to all but argue against the basic concept that radically altering the atmosphere on a multi million year basis is going to affect the net energy balance of earth, which over time is going to translate into a very different climate (and ocean
level) than the one we've comfortably come to rely on.
«This H2O negative - feedback effect on CO2 is ignored in models that assume that warm moist air does not rise and form sunlight - reflecting clouds, but remains as humid air near sea
level, absorbing infrared
radiation from the sun, and approximately doubling the temperature rises predicted from
atmospheric CO2 increases.
So it is the ordinary atmosphere that is radiating the
atmospheric LWIR
radiation; except at very high prehaps ionoospheric
levels where the mean free path is such that the GHG species can spontaneously decay to the ground state, before a collision occurs.
The biggest increase in background
radiation levels world wide was during the peak of
atmospheric weapons testing during the 1960s raising the
level by about 5 %.
As there are multiple periods in the geological record of tens of millions years in duration when CO2
levels were high and the planet was cold and when CO2
levels were low and the planet was warm, it appears there is a basic fundamental assumption in the model of
atmospheric radiation that is incorrect or there is an omission of another mechanism from the standard models of atmosphere
radiation.
This effective radiating
level depends on
atmospheric composition and, in particular, on those constituents that absorb terrestrial
radiation.
The only way CO2 could absorb any more IR than it is already absorbing is if 1) the surface started re-emitting more IR, which could only happen if more sunlight reached the surface, or 2)
atmospheric water vapor
levels dropped, freeing up more IR to be absorbed by CO2, in which case, warming would not occur, because that
radiation was already being absorbed by the water vapor that disappeared.