Model simulations of temperature and density trends in the upper thermosphere are generally consistent with satellite drag data, but some discrepancies remain. The most important of these is that satellite drag analyses under solar minimum conditions have measured density change of about −5% per decade near 400 km altitude, while model simulations of upper atmosphere cooling due to anthropogenic increases in carbon dioxide and other trace gases have predicted about half that rate. For solar moderate and maximum conditions, agreement is better. The rate of change is less during higher solar activity, because higher levels of nitric oxide cooling compete with the anthropogenic cooling. However, some past modeling studies used global mean models, and others attempted to scale to decadal rates from scenarios where carbon dioxide was doubled. Both of these approaches have shortcomings. Therefore, we have performed new, fully 3-D simulations, using the National Center for Atmospheric Research thermosphere-ionosphere-mesosphere electrodynamics general circulation model, to better quantify secular change rates at various levels of solar activity. These simulations use a 12 year baseline (approximately one solar cycle) in order to more directly compare with measured rates. Our new findings are in better agreement with observations for solar minimum conditions, approximately −5% per decade at 400 km, and are also still in reasonable agreement at solar maximum, approximately −2% per decade. This confluence of observation and simulation strengthens the case that some of the best evidence of the impact of anthropogenic global change on the upper atmosphere is the continued systematic decrease of thermospheric density.

full paper follow the link.
http://onlinelibrary.wiley.com/doi/10.1002/2014JA020886/full

Butt according to Grubb et al (2017) the models are still running too hot. ;)

It comes much after 2014 published 2015.

What does "better agreement" mean. It has gone from a Seriously Wild Ass Guess (SWAG) to merely a WAG?

when you have totally given up arguing with logic and and just resort straight to sarcasm its fair to say your out of ammo.

Pho Huc wrote on Sep 28^th, 2017 at 1:01am:

when you have totally given up arguing with logic and and just resort straight to sarcasm its fair to say your out of ammo.

There was sarcasm there?

Any more thoughts on what you thought sarcasm?


Pho Huc wrote on Sep 27^th, 2017 at 4:11am:

The most important of these is that satellite drag analyses under solar minimum conditions have measured density change of about −5% per decade near 400 km altitude, while model simulations of upper atmosphere cooling due to anthropogenic increases in carbon dioxide and other trace gases have predicted about half that rate.

So their model was wrong. They don't seem to have that equation right.


Pho Huc wrote on Sep 27^th, 2017 at 4:11am:

For solar moderate and maximum conditions, agreement is better.

Confirmation the model is not right,


Pho Huc wrote on Sep 27^th, 2017 at 4:11am:

. Therefore, we have performed new, fully 3-D simulations, using the National Center for Atmospheric Research thermosphere-ionosphere-mesosphere electrodynamics general circulation model, to better quantify secular change rates at various levels of solar activity. These simulations use a 12 year baseline (approximately one solar cycle) in order to more directly compare with measured rates. Our new findings are in better agreement with observations for solar minimum conditions, approximately −5% per decade at 400 km, and are also still in reasonable agreement at solar maximum, approximately −2% per decade.

So they used a new more powerful computer. the results -

Pho Huc wrote on Sep 27^th, 2017 at 4:11am:

Our new findings are in better agreement with observations for solar minimum conditions

Note - not good agreement, merely better agreement.

So they still don't seem to have the equation right. Is it because there are one or more unknown parameters, which remain unaccounted? What effect would any of these unknown parameters (if they exist) have on each other and on the whole?

A more powerful computer won't necessarily give the right answer, only faster.

There are simply too many unknowns.

from the paper  -

"Since the subsequent development of solar cycle 24 has been very weak, this raises the possibility of gradual change in solar forcing, both from energetic photon radiation and from magnetic variation that could confound attempts to quantify anthropogenic change. There is no known reason to suspect that this was an issue prior to 2007, during the period that most of the above analyses occurred. Nevertheless, this is a problem that increases the uncertainty on the observational inferences of secular trends and demands careful monitoring in the future."

But of course there is always the possibility of unknown reasons. ;)

YET another....

http://epaabuse.com/wp-content/uploads/2012/03/chickenlittle1.jpg