There is no doubt that:
- Average surface temperatures on Earth have increased by about 1.5⁰F (0.8⁰C) over the past century.
- The so-called Atmospheric "Greenhouse" Effect is real. That is, the presence of "Greenhouse" Gases in the Atmosphere, mainly water vapor (H2O) and carbon dioxide (CO2), makes the Earth surface some 60⁰F (33⁰C) warmer than it would be absent those gases. All else being equal, increases in Atmospheric CO2 tend to raise average global temperatures.
- Some of the temperature increase is due to human activities. Most of the recent rise in Atmospheric CO2 is due to human activities, mainly burning unprecedented amounts of fossil fuels (coal,oil, gas). Changes in land use due to worldwide agricultural and industrial development have reduced the albedo (reflectivity) of the Earth's surface, which contributes to warming.
The issues (and my answers):
- How much of the average global temperature increase is due to human activities?
- Most likely less than a third of the net warming over the past 100 years is due to human activities. That amounts to only about 0.5⁰F (0.3⁰C).
- The official Intergovernmental Panel on Climate Change (IPCC) claims that human activities are responsible for more than half of the warming. However, the lack of any statistically significant net warming over the past two decades, despite continued, mostly human-caused CO2 rise, casts serious doubt on that claim.
- How much of the warming is due to natural cycles not under human control or influence, and how dangerous is moderate warming?
- Most likely more than two-thirds of the warming is totally natural and due to the Earth's recovery from the "Little Ice Age" (LIA), a near-disastrous time of low crop yields that occurred between the years 1650 and 1850.
- The LIA followed the Medieval Warm Period (MWP) that occurred between 900 and 1200. History shows that the MWP and other moderately warm periods such as that associated with advances in the Roman empire, are generally beneficial to human life and civilization.
- Geological evidence and ice core data indicate that, well-prior to the appearance of humans on Earth, natural cycles of ice ages have recurred every 100,000 years or so. We are currently in a warming inter-glacial period between ice ages.
- Why have the predictions of continued rapid warming based on the official Climate Theory put forth by the IPCC failed to materialize?
- IPCC Climate Models, based on their Climate Theory, predicted that average surface temperatures would rise more than 0.7⁰F (0.4⁰C) between 1980 and 2015, in tandem with rising CO2 levels .
- Actual increases during this thirty-five year period have been less than a third of that estimate. The excellent, and highly reliable global satellite record, available since 1979, shows absolutely no net increase since 1998. The terrestrial record (surface-based thermometers) has recently been "adjusted" to yield a tiny increase, but nowhere near what had been predicted.
- The IPCC computer climate models are based on a Climate Theory that is far too sensitive to CO2 levels. The theory predicts that a doubling of Atmospheric CO2 will cause warming of between 1.5 to 4.5⁰C (3 to 8⁰F). Based on several decades of observations, the actual sensitivity of Climate to CO2 is most likely 0.5 to 1.5⁰C (1 to 3⁰F). That is the only reasonable explanation of the failure of the IPCC Climate Theory.
- According to Nobel Laureate Richard Feynman "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's wrong." Instead of following Feynman's advice and changing an obviously flawed Climate Theory, the IPCC scientists have "adjusted" the data! But, even the "adjusted" data fails to match up with the outlandish predictions of the IPCC Climate Models.
- What can and should be done to mitigate that increase?
- Very little beyond moderate "green" energy conservation along with transition from fossil fuels to alternatives such as water, wind, solar, nuclear, recycling of biowaste, and so on.
- Even if we in the US and Europe and other highly-developed countries take maximum "green" action, China, India, and other rapidly-developing economies will continue to increase their use of coal, oil, and gas, totally cancelling out any effect our actions may have.
Academic System Science Credentials
The Global Climate System is very complex, with innumerable interacting parts. I earned a PhD in System Science (1996) and therefore have academic credentials and knowledge of how to analyze, model, and attempt to understand complex systems. For example:
- Some components of the Climate System tend to provide positive feedback that increases warming, such as rising CO2 levels that cause surface temperature increases that, in turn, cause less CO2 to be absorbed by the oceans and rivers and more CO2 to out-gas from these water features, further increasing Atmospheric CO2.
- Other components cause negative feedback, such as the tendency of higher morning temperatures to produce greater evaporation and therefore more daytime clouds and thunderstorms earlier in the day.
- Thunderstorms and daytime clouds have a net cooling effect, making this process a type of automatic "thermostat". with the result stabilizing temperatures despite CO2 rise.
- Daytime clouds increase the albedo (reflectivity) of the Earth surface and therefore have a net cooling effect
- Nighttime clouds absorb and re-emit long-wave radiation, causing a net warming effect.
- Here is a simplified model constructed by a leading Warmist, Kevin Trenberth, a lead IPCC author and US NCAR researcher. See comments here.
My decades-long professional career was in System Engineering (IBM, Lockheed-Martin) so I have practical experience with really complex human-made systems.
- I have actual "hands-on" experience attempting to properly construct and evaluate computer models of complex avionics systems.
- I've "burnt my fingers" on models of the Doppler-Inertial Navigation systems that were in use prior to the advent of GPS.
- I've "stubbed my toes" on models of the multiple redundant data bus systems interconnecting multiple computers, sensors, displays, and actuators on modern aircraft.
- I know, from sometimes bitter experience, how difficult this task may become, and how easy it may be to fool ones-self.
I've also been an adjunct professor at the Thomas J. Watson School of Engineering at Binghamton University (NY) and the University of Maryland University College, teaching both under-graduate and graduate-level courses in Computer Science, Artificial Intelligence, Artificial Life, and System Engineering.
Online Climate Publication Credentials
So, please click on each of the CLIMATE SCIENCE TOPICS listed at the top of the right-hand column under the Blog title.