In 1970's, climatologists recognized the pressing need to find out whether the Earth receives more energy from the Sun than it radiates out. Here is how NASA Langley Research Center introduces the topic on
"The radiation budget represents the balance between incoming energy from the Sun and outgoing thermal (longwave) and reflected (shortwave) energy from the Earth. In the 1970's, NASA recognized the importance of improving our understanding of the radiation budget and its effects on the Earth's climate. Langley Research Center was charged with developing a new generation of instrumentation to make accurate regional and global measurements of the components of the radiation budget. The Goddard Space Flight Center built the Earth Radiation Budget Satellite (ERBS) on which the first ERBE instruments were launched by the Space Shuttle Challenger in 1984. ERBE instruments were also launched on two National Oceanic and Atmospheric Administration weather monitoring satellites, NOAA 9 and NOAA 10 in 1984 and 1986. "
Knowing the Earth Radiation Budget (a.k.a. Radiative Budget) is fundamentally important to forecasting the global climate trend, because according to the elementary thermodynamics the body temperature will increase if the energy input exceeds output, stay constant if the input equals output, and decrease if the output exceeds the input. This is the indisputable truth (I will resist temptation of calling it "the inconvenient truth") that ought to be recognized as fundamental to the Global Warming Hypothesis.
The ERBS satellite had been designed, launched, and operated successfully. The data it found have been extensively analyzed and placed by NASA as a public information on
The key finding is that the Earth Radiation is in balance, the energy radiated back to space equals that received from the Sun. The website conveys the above in a very informative graphic, designed to be clear to an educated non-specialist. It is reproduced below.
Review of the percentage numbers shows that about 30 % of the solar energy received is immediately reflected back, the remainder of 70 % is absorbed in various ways and radiated back through several channels, all adding up to the 100 % of the total input from the Sun. This graphic found its way into a number of publications, e.g., it can also be found in Wikipedia at http://en.wikipedia.org/wiki/Radiation_budget (but somehow it escaped attention of the policy makers). The Wikipedia article accounts also for non-solar energy sources such as geothermal, tidal friction, and waste heat from fossil fuel, all of them being negligibly small (it omits the cosmic rays and the heat radiated by living organisms).
To be honest, one must acknowledge that the above figure provides rounded up numbers for general public consumption and does not show the uncertainty due to the instrumentation limited precision (see Appendix for remarks about uncertainty). Therefore, the conclusion implied by the input/output equilibrium in the figure has to be stated in somewhat qualified terms as follows:
The ERBS data show the Earth solar energy input to equal the Earth energy output radiated back to space, within the satellite instrumentation margin of error. This conclusion puts the entire premise of the Global Warming hypothesis in serious doubt, to put it mildly.
The corollary to the above is that to reconcile this with the ground data showing glaciers retreating, arctic ice cover diminishing, and warming at various localities, etc., one should look into the thermal energy redistribution within the Earth as a system of many components. The fundamental thermodynamics law of the body temperature remaining constant in absence of net energy input does not preclude the possibility of the energy temporal redistribution within the body. Hence, the climate change research focus ought to be redirected from the causes of non-existent Global Warming to the mechanisms that control that redistribution. A very different issue, indeed.
A caveat is in order, the ERBS data are frozen in time and say nothing about the future of the Earth Radiation Budget balance. It is possible that it will change either toward positive (warming) or negative (cooling). It has in the past. There are satellites now operating (the CERES series) that will add temporal data, and we would certainly be well advised to keep the watch over the trend. The same applies to the CO2 issue. It is possible that if the CO2 level keeps increasing eventually it may force the balance toward positive (warming), but there is nothing in the ERBS data to indicate that this should be of any immediate concern.
Why the ERBS data that ought to be at the root of any serious debate about the climate change are so consistently ignored by the media, politicians, and those in climatology who should be the first to recognize the fundamental importance of these data? Is it because the data contradict the preconceived notions?
This note is posted in hope that it will arouse curiosity of the readers to seek answers to the above questions and to put them on the table in the national debate.
Appendix: For the readers inclined to dig deeper, here are a few pointers:
• NASA Technical Report providing depth of technical detail to the Earth's Energy
• Budget figure at http://eosweb.larc.nasa.gov/PRODOCS/erbe/quality_summaries s10n_wfov/erbe_s10n_wfov_nf_sf_erbs_edition3.html
• Paper by Kiehl & Trenberth; National Center for Atmospheric Research, Boulder, Colo., 1996; Bulletin of American Meteorological Society Vol. 78, No. 2, Feb. 1997 at http://www.gis.usu.edu/~mikew/awer3820/KiehlTrenbBAMS97.pdf. It discusses data obtained from satellite measurements obtained after the ERBS program ended. It also includes a graphic of the Earth's Energy Budget in a version much more detailed than the one included herein. There is a long list of references and the paper is a good point of entry into the subject literature.
• NASA Goddard Institute for Space Studies at http://icp.giss.nasa.gov/education/; It lists a number of relevant technical papers.
• Satellite instrumentation measurement accuracy: perusal of the above sources indicates that the uncertainty bounds are quite small: 0.07 % and 0.3 %.