Holocene Thermal Optimum

By Andy May

The Holocene Thermal Maximum, also called the Holocene Thermal Optimum, occurred at different times in different parts of the world but generally between 10,000 BP and 4,000 BP.  I use BP to indicate years before 2000.   The world ocean was probably 0.7°C warmer than today 8,000 BP. This is remarkable because the ocean heat capacity is 1000 times larger than the atmosphere’s according to the IPCC and NOAA.  Simple high school physics is all that is required to verify this, the calculation is described here.  What this means is that if you heated the atmosphere to 1000°C and transferred all of that heat to the ocean, the ocean would only warm 1°C once the heat was well mixed. We can draw two conclusions from these facts. First, the world was much warmer 8,000 BP than today and the total heat stored in the atmosphere and in the oceans was much greater. That 0.7°C represents the heat required to warm the atmosphere to over 700°C. This would never happen, of course, ocean-atmosphere heat transfer processes would work to move heat from the ocean to the atmosphere and back again to keep temperatures moderate and stable.

The second conclusion is that there is no magic 2°C tipping point. Raising todays atmospheric temperature 2°C involves an insignificant amount of heat relative to the total ocean/atmosphere heat present only 8,000 years ago. If the oceans absorbed 2°C worth of atmospheric heat, the ocean temperature would only go up a trivial and unmeasurable 0.002°C.

Climate and Human Civilization over the last 18,000 years, updated

By Andy May

This is an updated timeline of climatic events and human history for the last 18,000 years. The original timeline was posted in 2013. The updated full size (Ansi E size or 34×44 inches) Adobe Reader version 8 PDF can be downloaded here or by clicking on Figure 1. It prints pretty well on 11×17 inch paper and very well on 17×22 inch paper or larger. To see the timeline in full resolution or to print it, you must download it. It is not copyrighted, but please acknowledge the author if you use it.

Figure 1

References to the images and data are given in this essay as hyperlinks. I’ve done my best to verify the accuracy of the content by checking multiple sources. When references had different dates for the same event, I chose the most commonly cited date or the most prestigious source. All dates (except some in the modern era) are given as “BP” or before the year 2000 for simplicity, using 1950 (the radiocarbon zero) was too cumbersome.

The heart of the poster is the timeline of historical and climatic events. The Last Glacial Maximum (LGM) ended around 19,000 BP, the illustrations on the lower left of the poster illustrate what the world was like then. Much of the land area of the world was under ice or desert at the time and the exposed land had less precipitation than we do today.

Dr. Harold Lewis, why he resigned from the American Physical Society (APS)

Dr. Harold Lewis was a towering figure in physics. He resigned from the APS and detailed his reasons in an important open letter. In his view government research grants corrupted the APS. The environmental community has tried to demonize privately funded research as “corrupt” so that “pristine” government funding has a monopoly on research. In this way, by controlling the government funding, they can dictate outcomes. Thus man-made climate change becomes “fact,” although all data indicates otherwise. In Professor Lewis’s own words:

“It is of course, the global warming scam, with the (literally) trillions of dollars driving it, that has corrupted so many scientists, and has carried APS before it like a rogue wave. It is the greatest and most successful pseudoscientific fraud I have seen in my long life as a physicist.”

Dr. Benny Peiser’s notes on the UK Met Conference on Avoiding Dangerous Climate Change

Dr. Peiser’s notes on the 2005 UK conference are worth a read. He notes that Professor Yuri Israel, the chief climatologist at the Russian Academy of Science estimated that attempts to stabilize the world’s climate may cost 18 trillion US dollars! He encouraged adaptation and little mitigation. He was rudely and disrespectfully admonished by the IPCC crowd. Typical.

A Short Summary of Soon, Connolly and Connolly, 2015; “Re-evaluating the role of solar variability on Northern Hemisphere temperature trends since the 19th Century”

By Andy May

Soon, Connolly and Connolly (2015) is an excellent paper (pay walled, for the authors preprint, go here) that casts some doubt about two critical IPCC AR5 statements, quoted below:

The IPCC, 2013 report page 16:

“Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C (high confidence), extremely unlikely less than 1°C (high confidence), and very unlikely greater than 6°C (medium confidence).”

Page 17:

“It is extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together.”

Soon, Connolly and Connolly (“SCC15”) make a very good case that the ECS (equilibrium climate sensitivity) to a doubling of CO2 is less than 0.44°C. In addition, their estimate of the climate sensitivity to variations in total solar irradiance (TSI) is higher than that estimated by the IPCC. Thus, using their estimates, anthropogenic greenhouse gases are not the dominant driver of climate.

New Book: A Disgrace to the Profession, by Mark Steyn

Mark Steyn has written a wonderful new book on Dr. Michael Mann’s hockey stick and the controversy surrounding it. It is difficult to overstate the significance or impact of Mann’s Hockey Stick (Mann, Bradley, Hughes (23 April 1998), “Global-scale temperature patterns and climate forcing over the past six centuries” (PDF), Nature 392 (6678): 779–787, Figure 5, the paper is often abbreviated as “MBH”). The Hockey Stick appeared in Figure 1 of the Summary for Policymakers of the third IPCC Assessment Report (called “TAR” published in 2001) and it was prominently displayed in Al Gore’s movie “An Inconvenient Truth.” As the book clearly shows, both the graph and the movie have been thoroughly discredited by hundreds of scientists who have attempted and failed to reproduce Michael Mann’s hockey stick using his data and other proxy data.

#a-disgrace-to-the-profession, #climate-change, #hide-the-decline, #hockey-stick, #ipcc, #mark-steyn, #mikes-nature-trick, #scientific-fraud

Notes on the APS Workshop on Climate Change

In January, 2014 the American Physical Society (APS) held a one day workshop on climate change and invited six climatologists to participate.  A full transcript of the workshop can be found here. The six speakers are all very eminent climate scientists.  The discussion was limited to the physical basis of climate change and atmospheric physics was the predominant topic.  Three of the speakers lean to the alarmist view. That is they think we are headed toward a climate catastrophe due to man-made Carbon Dioxide. These are Dr. Held, Dr. Collins, and Dr. Santer.  The other three lean to the skeptical view and do not think we are headed to a climate catastrophe. These are Dr. Curry, Dr. Lindzen and Dr. Christy.  Short biographies of each of the speakers can be seen here. Someone new to the climate change debate would have a hard time telling the alarmists from the skeptics from this transcript. They were all very professional and they stuck to the science as their host, Dr. Koonin, requested. Climate science and the debate about it are much more complex than the media, the politicians and public know. This workshop drills down to the root of the disagreements and reading it reveals the considerable uncertainty in estimates of both climate sensitivity to CO2 and the effect of natural long term climate cycles.

On the new EPA Carbon Dioxide emission rule for power plants on Regulations.gov

This is a comment I put on regulations.gov about the proposed new rule.

The key assumption in this rule is that man-made Carbon Dioxide is harmful to the environment by altering our climate. I do not think this is proven. The key elements of the debate on man-made catastrophic climate change are actually pretty simple. Obviously, climate changes and it is warmer than it was 150 years ago, so these facts are not in dispute. It is the “man-made” and the supposed impending catastrophe that are controversial.

Now, if we were to double the amount of CO2 in the atmosphere from the current 400 PPM (0.04%) to 800 PPM physics and chemistry would predict that the atmospheric temperature would increase a trivial 0.75 degrees C. The climate alarmists have used global circulation models (GCM’s) with a climate sensitivity factor that increases this to three or four degrees C by assuming positive feedbacks. These models generally assume that as CO2 goes up, water vapor will increase and since water vapor is a much stronger greenhouse gas than CO2 they speculate that temperature will spiral out of control with catastrophic effects. That is pretty much their case.

The problems with this are twofold. First there are no measurements to support the idea that water vapor will increase with CO2. In fact, the models suggest the highest rate of warming should be in the tropics because most water vapor is there and most heat enters the atmosphere there. But no significant warming has occurred in the tropics (or in Antarctica for that matter), warming has been almost entirely in the northern Northern Hemisphere and especially in the Arctic. Further, if more water is held in the atmosphere wouldn’t we get more clouds? Will the clouds make us warmer or cooler? No one knows, clouds are not in the GCM’s. Second, the GCM’s have not been successful in predicting anything yet. Observations have shown no increase in global temperature since 1998, but the models predicted an increase. The proportion of CO2 in the atmosphere has increased, why no increase in temperature?

We need to remember that man’s burning of fossil fuels contributes only 8% of the CO2 that goes into the atmosphere; respiration, microbial activity, volcanism, ocean outgassing, etc. provide the rest. We also need to remember that the average CO2 in the atmosphere after the dinosaurs and until the ice age (which we are still in) is 800 ppm. Atmospheric CO2 only decreased to 300 PPM (and perhaps less) due to the ice age. The article noted below provides actual evidence (not a computer model) that the additional climate sensitivity due to doubling CO2 to 800 ppm will increase the average temperature 1.093 degrees C. A trivial amount and a fraction of what the IPCC circulation models predict. This makes much more sense and is in line with what has been seen in the Earth’s history. If this article stands the test of time, it kills the entire alarmist argument. Some have said that computing or measuring climate sensitivity to CO2 is a fool’s errand and perhaps this is so. But, either way the alarmist argument is destroyed. It is far from certain that climate change is a problem or even unusual.