Son of Mulder.
On the subject of GCMs, it's a while since I visited the CA blog so I was surprised to read this;
http://www.climateaudit.org/?p=6234#more-6234Super-Parameterization! Well I did say that they should treat GCMs like video gaming machines. This extra resolution to each cell apparently shows WV and low cloud as more negative than previously shown by models (wouldn't you just know it). However, it wouldn't matter if they duplicated a parallel Earth accurately, they could only hind cast because we can't predict the future more than for a few days ahead with an acceptable level of certainty.
Reading about this brought me to remember our discussions on C4 about constant average global RH and the possibility that total SH + atmospheric water could be a metric for an average 10 day global temp. Well moving on from that, there are an awful lot of metrics that seem to coincide with one-another in a "loose relationship" that may explain a tipping point or two. I'll explain.
The Physical Proponents.
1. Sea surface temp (SST) and boundary layer atmosphere temp are ultimately responsible for the level of specific humidity (SH) [physical and factual observation].
2. Diurnal temp instability, land area and contour, advection, etc. are responsible for Earth's unique default average global relative humidity (RH) [physical and factual observation].
3. Although solar variance is minor, the propensity of sunspots is directly proportional to the level of ultraviolet (UV) insolation of Earth and this varies greatly [physical and factual observation].
4. The average global temp anomaly record indicates much coincidence of elevated temps during sustained high sunspot count periods. Thus, sustained elevated UV insolation levels seem to positively affect temps [visual comparison of graphic material with provenance].
5. Infrared (IR) and visual spectra of radiation become extinct after passing through only several metres of water and ice. However, the UV spectra of radiation that strike the Earth's surface can pass several hundreds of metres into water and ice before extinction, it also is virtually unimpeded by cloud which only diffuses UV [physical and factual observation].
6. About 90% of the greenhouse effect (GHE) for outgoing IR radiation is due to WV. Thus, about 90% of outgoing IR is thermalised below the mid troposphere region by WV, and low cloud also heavily retards, and latently buffers, outgoing IR radiation [accepted radiative theory, and physical and factual observation for latent buffering].
7. Milankovich Cycles can predict total solar insolation (TSI), but don't resolve many outcomes of historical climate. However, Milankovich Cycles don't include the level of sunspot activity (and UV insolation level) that can become the donor of energy that is able to preclude, or exclude, an ice age, as a short wavelength radiation absorbed gives more energy than a longer wavelength's radiation's absorbed energy [conjecture, as I'm unaware of any accepted comparison that combines Milankovich Cycles against sunspots with a radiative theory's impact].
The Hypothesis.
Although TSI doesn't alter to any appreciable degree due to a Milankovich Cycle, the insolation of UV to the Earth is always changing dependant upon sunspot propensity. The greater the sunspot manifestation, the greater the UV insolation level, and as we know from the history of the Maunder Minimum that this variability of UV is a causal factor to Earth's global temperature alteration (this is where I'd normally just post a link to the page of a site, but this site isn't made that way, so).
http://www.climate4you.com/Now that you see the index page, click on the "Sun" category in the L/H sidebar to see the page that I reference.
Thus, UV is a major influence for any change to climate, or at the very least, temperatures!
It's easy to make such a statement, but it's important to describe the 'rationale' behind the 'statement' for better understanding (I'm getting back into the habit of single quotes for important parts of the post again. Sorry!).
Dependant upon the Milankovich Cycle 'level' of forcing, the solar UV radiance determines the glaciation, or non glaciation phase of Earth's climate because UV is the source of heat to the lower ocean depths that can carry the Earth through a 'glaciation phase' without it's 'actual glaciation'. I'm happy that we are at a 'high insolation point' of a 'Milankovich Cycle' at this point of 'solar minimum'.
What do you think?
Best regards, suricat.
Enjoy!!