Seasonal Radiative Response

 

[This was originally posted in 2013 on Judith Curry’s site and was authored by CASF member, Steve McGee.  We have included it here as part of the CASF Archive.  Posted on December 26, 2013 | 169 Comments]

by Steve McGee

In science, one likes to have more examples than theories. – Dusan Djuric

Those words, spoken whimsically about cosmology, apply to climate science as well. The theory of the sensitivity of climate to the radiative SFCTforcing imposed by a doubling of carbon dioxide suffers from a lack of observed, repeatable examples. Paleo-climate studies carry with them the uncertainty of the proxy data and unmeasured assumptions on which they are based. Studies regarding the forcing from volcanoes and other transient events may not be repeatable for some time. However, Lindzen et. al. 1995 (link ) and Ramanathan and Inamdar in Frontiers of Climate Modeling, 2006 (link ) each have pointed out that the seasonal variation of earth temperature is quite large and possibly a surrogate for climate change. With this in mind, I set out to determine how the seasonal variation Continue reading “Seasonal Radiative Response”

Is Earth in Energy Deficit?

The concept of ‘missing heat’ implies that a surplus of energy exists to be missed. And the NASA GISS Model E projects a trend of increasing energy surplus.

 

[This post on earth's energy budget analysis origninally appeared on Judith Curry's web site and was authored by CASF member, Steve McGee,in 2013.  We have added it to this site as part of our archive.  Posted on  | 673 Comment]

by Steve McGee

Unlike many fiscal budgets, earth’s energy budget is widely believed to be in surplus.

With each year of increasing amounts of greenhouse gasses, earth is modeled to send less energy outward than it receives from the sun. This energy surplus, as understood, continues until the global average temperature rises sufficiently to restore balance by emitting more energy in accordance with the Stefan-Boltzmann Law. Indeed, the concept of ‘missing heat’ implies that a surplus of energy exists to be missed. And the NASA GISS Model E projects a trend of increasing energy surplus. The runs of Model E for “Dangerous Human-Made Interference” (from 2007) A1B scenario ( available at  link) yield this projection for net radiance at the top of the atmosphere:

GISS_Dangerous_LatTime

attachment-01

Notice the increasing trend of anomalous net radiance.

With this in mind, but on another matter I recently examined the Climate Forecast System Reanalysis. The CFSR is a newer reanalysis described by Saha, Suranjana, and Coauthors, in 2010: The NCEP Climate Forecast System Reanalysis. Bull. Amer. Meteor. Soc., 91, 1015.1057. doi: 10.1175/2010BAMS3001.1

The CFSR monthly data sets are available at [link].

The CFSR is the first reanalysis from NCEP to use radiance observations from the menagerie of past satellites. The CFSR also uses the AER RRTM radiative model to fill in the gaps of satellite data. The RRTM is the same radiative code used by many climate models. By subtracting the top of the atmosphere outgoing infrared from the net shortwave radiative flux, one arrives at the net radiative flux. And by dividing the outgoing shortwave radiative flux by the incoming shortwave radiative flux, one arrives at albedo. Examples for March of 1979 appear as:

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Due to missing values, all data for the year 1994 are excluded. By calculating the spatially weighted global annual averages, the time series of various fields yield interesting results. The data for the top of the atmosphere net radiance appear as:

AnnualCFS_NRAD

The CFSR Net Radiance data indicate radiative deficit following the El Chichon volcanic eruption in 1982, and again following the Mount Pinatubo volcanic eruption in 1991. Also, the peak net radiative surplus appears during 1997 which coincides with the anomalously warm El Nino event. I was quite surprised, however, to note that the years 2001 through 2008 indicate net radiative deficit and that the overall trend was toward decreasing net radiance.

Should I have been surprised? Perhaps not. Net radiation, particularly the shortwave component, is known to be quite difficult to measure because shortwave reflection varies greatly with respect to the angle of observation  depending upon the composition, size, shape, and orientation of clouds and earth’s surface. Further, the very process of reanalysis can add spurious errors. That is why NCAR ( the National Center for Atmospheric Research ) warns that reanalysis should not be equated with “observations” or “reality.”

Still, while not “observation” nor “reality”, the CFSR does represent a best assessment of  the recent climate based on observations and the same radiative codes that lie within the prognostic climate mod

So what does this imply?

To the extent that the CFSR radiance is accurate, it implies that earth was in radiative deficit, not surplus, for the decade of the 2000s and that for this decade, there is no ‘missing heat’ to be found.

The negative trend in CFSR net radiation implies a divergence from the NASA GISS model projections cited above.

The CFSR net radiative deficit also implies that energy loss to space, rather than shifting of energy within the climate system may be responsible for the negative trend since 2001 in many of the global temperature data sets.

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Biosketch
:  Steve McGee has a bachelor of science degree in meteorology. His long career of software engineering includes the development of numerous defense related systems providing analysis and display weather and atmospheric effects.

STILL Epic Fail: 73 Climate Models vs. Measurements, Running 5-Year Means

by Roy W. Spencer, Ph. D.

[This short post was published by Roy W. Spencer on June 6th, 2013 and has been reproduced here with the permission of the author.  Ed.]

In response to those who complained in my recent post that linear trends are not a good way to compare the models to observations (even though the modelers have claimed that it’s the long-term behavior of the models we should focus on, not individual years), here are running 5-year averages for the tropical tropospheric temperature, models versus observations (click for full size):

CMIP5-73-models-vs-obs-20N-20S-MT-5-yr-means
In this case, the models and observations have been plotted so that their respective 1979-2012 trend lines all intersect in 1979, which we believe is the most meaningful way to simultaneously plot the models’ results for comparison to the observations.

In my opinion, the day of reckoning has arrived. The modellers and the IPCC have willingly ignored the evidence for low climate sensitivity for many years, despite the fact that some of us have shown that simply confusing cause and effect when examining cloud and temperature variations can totally mislead you on cloud feedbacks (e.g. Spencer & Braswell, 2010). The discrepancy between models and observations is not a new issue…just one that is becoming more glaring over time.

It will be interesting to see how all of this plays out in the coming years. I frankly don’t see how the IPCC can keep claiming that the models are “not inconsistent with” the observations. Any sane person can see otherwise.

If the observations in the above graph were on the UPPER (warm) side of the models, do you really believe the modelers would not be falling all over themselves to see how much additional surface warming they could get their models to produce?

Hundreds of millions of dollars that have gone into the expensive climate modelling enterprise has all but destroyed governmental funding of research into natural sources of climate change. For years the modelers have maintained that there is no such thing as natural climate change…yet they now, ironically, have to invoke natural climate forces to explain why surface warming has essentially stopped in the last 15 years!

Forgive me if I sound frustrated, but we scientists who still believe that climate change can also be naturally forced have been virtually cut out of funding and publication by the ‘humans-cause-everything-bad-that-happens’ juggernaut. The public who funds their work will not stand for their willful blindness much longer.

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Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center, where he and Dr. John Christy received NASA’s Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer’s work with NASA continues as the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite. He has provided congressional testimony several times on the subject of global warming.

Dr. Spencer’s research has been entirely supported by U.S. government agencies: NASA, NOAA, and DOE.  He has never been asked by any oil company to perform any kind of service. Not even Exxon-Mobil.