GLOBAL WARMING IS REAL, BUT NOT A BIG DEAL
1) Some of the net Global Warming since 1880 is undoubtedly due to human actions. The Atmospheric "Greenhouse" Effect is real and water vapor (H2O) and carbon dioxide (CO2) are "greenhouse" gases.
2) The actual temperature rise and human responsibility for it have been exaggerated. By their repeated and substantial "adjustments" to the US temperature record, the Official US Climate Team (NASA GISS) has admitted that it is unreliable.
3) Official Climate Theory is flawed because it is "handcuffed" to CO2 levels. None of the official Climate Models predicted the current 17-year "pause" in warming. CO2 levels continue to rise rapidly, but the predicted warming has not occurred.
Going from left to right on the above graphic:
Atmospheric “Greenhouse” Effect, responsible for about 59°F (33°C) warming. This is the Natural Process that makes life on Earth as we know it possible. The mean temperature on the surface of the Earth is about 59°F (33°C) warmer due to Atmospheric absorption of long-wave radiation by "greenhouse" gases, and the subsequent "back-radiation" of some of this heat energy towards the Earth surface. (See my WUWT Visualizing series [Physical Analogy, Atmospheric Windows, Emission Spectra, and Molecules/Photons Light and Heat])
Ice Age Warming and Cooling, are Natural Cycles that have occurred about every 100,000 years according to the ice core records from the past 400,000 years. Since these cycles occurred well before humans appeared on Earth, they must be entirely natural. The climate is always changing, with up and down temperature jigs and jags at all time scales. The major Ice Age Cycles change temperatures over a range of about 13°F (7°C ).
Mean Global Warming Since 1880, According to the Official NASA GISS and IPCC Accounting, is 1.4°F (0.8°C). According to the IPCC, the majority of this Global Warming is due to human activities (mainly unprecedented burning of fossil fuels and land use that has reduced the albedo of the Earth). I have interpreted "majority" to mean about 70% and have therefore allocated 1°F (0.6°C) to Human-Causation and the remaining 0.4°F (0.2°C) to Natural Cycles.
Please notice that the Human-Caused warming is a minor uptick in temperature compared to the variations due to the Natural Cycles of Ice Age warming and cooling and the major Natural Process warming due to the Atmospheric "Greenhouse" Effect!
Even that small amount of warming is most likely exaggerated and NASA GISS and the IPCC have the proportion of human-caused and natural backwards. Actual warming is most likely about 1.0°F (0.6°C), with about 0.8°F (0.5°C) due to Natural Cycles, and the remaining 0.2°F (0.1°C) due to Human-Causation.
Move from New York to Florida, My wife and I experienced considerable warming when we retired from full-time employment and moved from Upstate New York to Central Florida. The average temperature in Florida is about 20°F (11°C ) warmer than that in New York. While not exactly "Global" Warming, this warming was certainly due to our Human-Caused decision to move south, and, of course, we enjoy the resulting moderately higher temperatures :^). Our voluntary move caused many times more degrees of warming than the global warming since 1880!Yearly and Daily Warming and Cooling: Natural Cycles of the YEARLY 43°F (24°C ) temperature range in Central Florida (July mean minus January mean), and Natural Cycles of the DAILY 19°F (11°C ) temperature range we experience here. Please notice that these ranges are much larger than the Natural Cycles of the Ice Ages, and they recur on a daily or yearly basis in the temperate zones of the Earth. Again, these daily and yearly temperature cycles cause many times more degrees of warming and cooling than all the global warming since 1880!
THE OFFICIAL TEMPERATURE RECORD IS UNRELIABLE
The blink chart below illustrates how US thermometer data from the early 1900's to 1998 has been "adjusted" by NASA GISS to COOL DOWN data prior to the 1970's and WARM UP data after the 1970's. Please note that 1998, the warmest year of the 1990's, is now shown as warmer than 1934, the warmest year of the 1930's. When the same chart was originally published in 1999 by the same US-government-supported institute, the relationship was reversed. The net change in this relationship is 1.154°F (0.641°C). Both charts were downloaded in March 2014 from http://www.giss.nasa.gov/
We know that the US thermometer record is so unreliable that it has had to be "adjusted" several times by the official US Climate "Team" at GISS, see The Past is Not What it Used to Be, and Skeptic Strategy. and Climate Change Controversy.
Unless we believe that the world temperature record is more reliable than the US record, it is likely the world record has also been similarly "adjusted". Therefore, I have discounted the GISS estimate of Global Warming by about 30%, so actual warming is about 1.0°F (0.6°C). I believe the IPCC has over-estimated Climate Sensitivity by a factor of two or three, so I have allocated the majority of the warming 0.8°F (0.5°C) to Natural Cycles, and the remaining 0.2°F (0.1°C) to Human-Causation.
PLEASE NOTE: I do not claim that the "adjustments" are wrong, only that the underlying temperature data is unreliable. If that data was reliable, there would be no need for the repeated re-analysis and "adjustments" that have been done by the official Climate Team.
OFFICIAL CLIMATE MODELS HAVE FAILED
We have had good satellite records of Global Temperatures since 1979, so we no longer need to rely on the unreliable terrestrial temperature record. As shown in the chart below, the satellite record (blue arrows) shows moderate warming from 1979 to about 1996, and then a "pause" in warming that continues to this day. The wiggly lines on the chart show the theoretical Climate Models, with the heavy red line (and the red arrow) indicating the average of all the models. All of the official Climate Models have failed because the underlying Climate Theory is flawed.
Climate Sensitivity is the Mean Temperature Rise expected if CO2 levels double. So far, from 1979 to the present, CO2 has increased from about 330 ppmv to nearly 400 ppmv, a 40% rise. If that rate of CO2 rise continues, as it almost certainly will given the rapid industrialization of China, India, and other countries, the 1979 CO2 level will double by 2060.
The IPCC claims Climate Sensitivity is in the range of 2.7°F (1.5°C) to 8.1°F (4.5°C), and their Climate Models reflect that range. As the chart above indicates, when their Climate Models are run from 1979 to 2013, the expected temperature rise is about 1.6°F (0.9°C) . However, the actual temperature rise since 1979 is only about 0.3°F (0.17°C) , a fraction of what was predicted!
Based on the evidence of this chart, that the IPCC has over-estimated Climate Sensitivity by at least a factor of two to three. I believe actual Climate Sensitivity is closer to the range of 1.0°F (0.6°C) to 2.0°F (1.1°C).
THE SCIENTIFIC METHOD vs THE OFFICIAL CLIMATE THEORY
As Richard Feynman famously said,
It doesn't matter how beautiful your theory is. It doesn't matter how smart you are. If it doesn't agree with experiment it is wrong!The Official Climate Theory is based on a gross over-estimate of CO2 Climate Sensitivity. Reliable satellite-based temperature DATA since 1979 proves that the Official Climate Theory is WRONG by a factor of at least two or three.
According to the Scientific Method, if your theory doesn't agree with the observational DATA, you need to change your THEORY.
The Official Climate Team seems to have changed the DATA!