What to do about global warming - 7: Risk Management

In our previous installment we considered methods other than carbon dioxide sequestering as means to control global warming using geoengineering to increase earth’s average albedo.

As discussed in the first installment we accept the premise that human-generated CO2 causes unacceptable atmospheric warming. In the second installment we showed the life cycle of CO2 in the atmosphere and how it persists for centuries and millennia after emissions. In the third installment we showed how the emitted CO2 affects global temperatures and demonstrated that no amount of CO2 emission control will be sufficient to prevent reaching the 2 °C “tipping point”. In the fourth installment we examined carbon dioxide sequestering as a means to control global average temperature, calculated the net sequestering required to prevent exceeding the tipping point, and compared some different options regarding their effectiveness and cost. In the fifth installment we examined some of the thermodynamics of the global system, the heating sources and their relative contributions, and identified increasing the earth’s albedo as another means to control global warming in addition to attempting to remove carbon dioxide.

In this final installment we consider the risk vs. cost of various alternatives to address global warming. What should we do about global warming?

We have assumed all along that global warming is real, human-induced via emissions of carbon dioxide and other gases, and potentially catastrophic for humans and the earth. Given these, we should be willing to "pay any price" to combat it, even the several hundred Trillion US$ identified in the last article. Right?

Or maybe not. As we noted, economists point out that the potential costs of preventing, combating or mitigating global warming might leave us poorer than simply adapting to it, especially when it comes to the effects on the poorest people of the earth. Nobel-Prize-winning economist William Nordhaus has pointed out that when one considers the costs of carbon dioxide mitigation vs. adaptation to the effects, “his own model shows that the UN’s target would make humanity poorer than doing nothing at all about climate change.” (Murphy, 2019) [emphasis in original]. It may be the case that doing nothing to prevent warming might be preferable to doing something that is unacceptably expensive, and apply financial resources to adapting to the effects of global warming, e.g., protecting or relocating cities.

After all, sea levels have been rising for hundreds and thousands of years since the end of the last ice age, and even since the end of the "little ice age" of the 17th-18th centuries. Humans have adapted, whether the rivers froze in winter, overflowed in the spring, or Greenland could grow crops or not. Humans adapt, even to unfixable "problems".

Historical Temperature vs. Time

We began this series with a graphic (Figure 1) of relatively modern temperatures. Two characteristics may be noted: there is no pre-industrial context, as the data only begin at 1880 (and thank you to commenters who noted this limitation). Second, this reflects only surface temperatures. While this is not surprising for the earlier data, the latest data could be augmented with satellite data that measures the overall atmospheric temperatures rather than just the surface temperatures (Spencer, 2018). The latter are known to be affected by the "urban heat island" effect where surface temperatures increase over time primarily because of encroaching urban effects, e.g., increased streets, asphalt, buildings, etc., that absorb and retain more heat from the sun than previous pastureland or forests (i.e., lower albedo). So temperature increases over time do not reflect global average temperatures.

Figure 1. Recent global mean surface temperatures (NASA Earth Observatory, 2010).

Is the latest temperature increase extraordinary?

A more complete temperature history that includes recent satellite measurements is displayed in Figure 2. The current temperature increases are not that extraordinary compared with the Roman warm period (0-200) and the medieval warm period (900-1100. The modern temperature increase also comes after the deep freeze in the depths (1700) of the “little ice age”. So the 1800s and 1900s are part of the temperature rebounding from recent low temperatures.

Figure 2. Modern period temperatures, including the Roman warm period (0-200), medieval warm period (900-11)), and “little ice age” (1700) (Ljungqvist, 2010).

Have Temperature and CO2 concentrations ever been this high?

If we look further back in time (Figure 3) we can see that earth’s temperatures have been much higher, as much as 10°C according to chemist Dr. Vincent Gray (Gray, 2013). Gray synthesized several sources to create the graph (“Analysis of the Temperature Oscillations in Geological Eras C. R. Scotese (2002)” appears to be derived from (Worsley, 1994), (Ruddiman, 2001), and (Pagani, 2005)).

As the graphic shows, carbon dioxide concentrations are estimated to have been as much as ten times higher (4000 ppm) than current values and CO2 levels appear to be uncorrelated to temperatures. (Gray, 2013) concludes, “The theory that carbon dioxide concentration is related to the temperature of the earth’s surface is therefore wrong.”

Figure 3. Carbon dioxide concentration and temperature variations over geologic time (Gray, 2013).

This leads some to discuss the current situation as a “carbon dioxide famine” (Happer, 2016). What we are seeing since the 1800s is a gradual “greening” of the earth (more land covered by richer forests) in response to the higher CO2 concentrations, much the way agriculturists enhance the CO2 of greenhouses to increase plant growth rates. (Idsoe, Plant Growth Database, 2019)

Are there other potential causes of warming?

If carbon dioxide is not the cause of global warming, what else could cause it? As we said in the fifth article, the problem is the sun. Variations in the earth’s orbit and rotation have been determined to be sufficient to cause the observed changes in net solar insolation. (Huff, 2019) cites the work of Milutin Milankovitch:

"When Milankovitch first put forward his model [(Milankovitch, 1941)], it went ignored for nearly half a century. Then, in 1976, a study published in the journal Science [(Hays, 1976)] confirmed that Milankovitch’s theory is, in fact, accurate, and that it does correspond to various periods of climate change that have occurred throughout history.

"In 1982, six years after this study was published, the National Research Council of the U.S. National Academy of Sciences adopted Milankovitch’s theory as truth, declaring that [(National Research Council, 1982)]:

""… orbital variations remain the most thoroughly examined mechanism of climatic change on time scales of tens of thousands of years and are by far the clearest case of a direct effect of changing insolation [solar heating] on the lower atmosphere of Earth."

"If we had to sum the whole thing up in one simple phrase, it would be this: The biggest factor influencing weather and climate patterns on earth is the sun, period. Depending on the earth’s position to the sun at any given time, climate conditions are going to vary dramatically, and even create drastic abnormalities that defy everything that humans thought they knew about how the earth worked."

Other historical variations in solar insolation correlate to lower global temperatures due to lower sunspot activity, e.g., Dalton Minimum (about 1800), Maunder Minimum (about 1650). There is reason to attribute at least some of the earth’s temperature variation to variations of solar insolation due to net solar output and changes in earth’s orbit.

What should we do? What if we’re wrong?

In deciding a course of action, we must consider (a) the probability that the cause is real (CO2-induced warming vs. other causes), (b) the probability that the effect based on the cause is real (°C/tonne CO2), and (c) the expected cost of mitigation (reducing CO2 or increasing albedo) vs. the cost of humans adapting to the revised environment.

For the first two probabilities, (IPCC, 2018) asserts (p. SPM-4) that

"A1. Human activities are estimated to have caused approximately 1.0°C of global warming above pre-industrial levels, with a likely range of 0.8°C to 1.2°C. Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate. (high confidence),"

where likely means “66%-100%” per (IPCC, 2018). For the IPCC, these probabilities are virtually certain, which is the position with which we began this analysis. What about the cost of mitigation vs. the costs of damage and adapting?

(Lomborg, 2007) estimates (p. 31) that the estimated damage from one additional ton of CO2 in the atmosphere is about two US dollars with a maximum cost of $14. This is a much lower cost than that of sequestration discussed in the prior article, in the range of US$30-50/tonne. Using US$14/ton for the cost of damage yields US$15.4/tonne. Using 1.37°C/Tt (trillion tonnes CO2) derived in the third article yields an “expected damage” of up to US$11.2 Trillion/°C. This is how much we should be willing to spend to prevent the problem. This is much lower than the estimated cost of prevention (CO2 sequestering or increasing earth’s albedo other than by marine cloud brightening) as of order US$200 Trillion/°C prevented. So it makes more sense in general to focus on adaptation rather than prevention.

Other effects: Sea level rise and ocean acidification

(Lomborg, 2007) also estimates (pp. 60-61) that estimated sea level rise has continued at about one ft/century, both historically and projected into the future. The IPCC estimates that it would cost US$5-6 billion to protect USA from a 3-ft rise in sea level (IPCC, 2001). The Netherlands has historically used this approach to reclaim land from the North Sea. Even the USA uses this technique where existing land is below sea level, e.g., New Orleans, LA.

(Idsoe, Ocean Acidification Database, 2019) suggests that the effects of ocean acidification (declining pH) are not as deleterious to ocean plants and animals as is sometimes asserted.

Conclusion

Doing nothing about the CO2 and adapting to the measurable impacts if and when they happen may be the best use of global financial resources. At the same time, the estimated (Lomborg, 2019) relatively low cost of marine cloud brightening (US$10 Billion) suggests that further research and pilot projects for this technique would be prudent risk management. And further research to confirm (Milankovitch, 1941) and other sun-driven causes is also prudent. Funds for these activities should come directly from existing expenditures regarding carbon dioxide emission reductions.

If temperature is the problem, then risk mitigation of temperature does not require eliminating all CO2 emissions, which would be disruptive, expensive, and ineffective on any time frame of interest. In contrast, deploying some means to increase albedo can be done immediately and incrementally, and terminated or removed if the risk is not realized or other problems arise.

One could reasonably expect that in 200 years we would have either determined that carbon dioxide is not a threat at higher concentrations up to some limit, determined a different tipping point in terms of higher temperatures or CO2 concentrations, determined that the sun is the primary cause of global temperature variations, and/or determined some affordable methods (e.g., different energy technologies) to mitigate the carbon dioxide. It does not seem prudent to devote US$200 Trillion to preventing further global average temperature increases.

Epilogue

Individual actions: Walking the Talk

Regardless of any effect on global warming, at a minimum we as individuals should consistently strive to destroy the least exergy. That is, we should strive to be more efficient in our use of energy. This both minimizes our individual costs and, more importantly, reduces overall use of resources that control the market price of energy used by the poorer among us. Driving larger cars with lower gas mileage, while safer for occupants, increases demand for gasoline and marginally increases the price for all users, including those least able to afford it. On the other hand, increasing the supply of such fuels has the opposite, declining effect on fuel prices, and should be encouraged.

Similarly, those advocating controlling CO2 emissions should be leaders in reducing energy use, and be first to forswear the use of private jets, and instead should fly commercially and only as necessary. To do other is rank hypocrisy. Such an attitude is also evident in those who demand control of CO2 emissions because of the potential impact on rising sea-levels yet buy ocean-front property. They clearly do not believe there is a threat in their lifetime. These actions signal that such individuals either do not believe their own words (hypocrisy and cynicism) or are ignorant about the inconsistency. In either case they should therefore not be making such pronouncements.

Mr. and Mrs. Patient: Reprise

Having transported Mr. Patient to the hospital with high fever and immediately placed Mr. Patient in a cool-water bath, the doctors later return with test results indicating that there is no ongoing infection as the cause. Further discussions with Mr. and Mrs. Patient lead to an understanding that Mr. Patient was simply dehydrated and overheated from lying in the sun that afternoon.

Thank you for joining me on this analytical journey, and for informative comments posted. My hope is that the information will assist each reader in making rational and effective decisions regarding what to do about global warming. References have been included so that you may continue your own investigations.

Works Cited

Gray, V. (2013, June 4). NZ Climate Truth Newsletter, NO 312 June 4th 2013, Carbon Dioxide. Retrieved from What's Up With That?: https://wattsupwiththat.com/2013/06/04/dr-vincent-gray-on-historical-carbon-dioxide-levels/

Happer, W. (2016, February 22). A Primer on Carbon Dioxide. Retrieved from CO2 Coalition: https://co2coalition.org/2016/02/22/primer-carbon-dioxide-climate/

Hays, J. D. (1976). Variations in the Earth's Orbit: Pacemaker of the Ice Ages. Science, 194(4270), 1121-1132.

Huff, E. (2019, August 30). NASA admits that climate change occurs because of changes in Earth’s solar orbit, and NOT because of SUVs and fossil fuels. Retrieved from Natural News: https://www.naturalnews.com/2019-08-30-nasa-admits-climate-change-not-caused-by-suvs-fossil-fuels.html

Idsoe, C. (2019, December 5). Ocean Acidification Database. Retrieved from CO2 Science: https://www.co2science.org/data/acidification/results.php

Idsoe, C. (2019, December 5). Plant Growth Database. Retrieved from CO2 Science: https://www.co2science.org/data/plant_growth/plantgrowth.php

IPCC. (2001). TAR Climate Change 2001: Impacts, Adaptation, and Vulnerability. Cambridge: Intergovernmental Panel on Climate Change, Cambridge University Press. Retrieved from https://www.ipcc.ch/report/ar3/wg2/

IPCC. (2018). Global Warming of 1.5°C", Summary for Policymakers. Intergovernmental Panel on Climate Change (IPCC), 6 October 2018.

Ljungqvist, F. C. (2010). A New Reconstruction of Temperature Variability in the Extra-Tropical Northern Hemisphere During the Last Two Millennia. Geografiska Annaler Series A Physical Geography, 92(3), 339–351. doi:10.1111/j.1468-0459.2010.00399.x

Lomborg, B. (2007). Cool it: The Skeptical Environmentalist's Guide to Global Warming. New York: Alfred A. Knopf.

Milankovitch, M. (1941).Canon of Insolation and the Ice-Age Problem (Kanon der Erdbestrahlung und seine Anwendung auf das Eiszeitenproblem) . Belgrade: Royal Serbian Academy Special Publications. 

Murphy, R. P. (2019, November 10). William Nordhaus versus the United Nations on Climate Change Economics. Retrieved from The Library of Economics and Liberty: https://www.econlib.org/library/Columns/y2018/MurphyNordhaus.html

NASA Earth Observatory. (2010, June 3). Global Warming. Retrieved from https://earthobservatory.nasa.gov/features/GlobalWarming/page2.php

National Research Council. (1982). Solar Variability, Weather, and Climate. Washington, D.C.: National Academy Press.

Pagani, M. J. (2005). Marked Decline in Atmospheric Carbon Dioxide Concentrations During the Paleogene. Science, 309(5734), 600-603. doi:10.1126/science.1110063

Ruddiman, W. F. (2001). Earth's Climate: Past and Future. NY: W. H. Freeman & Sons.

Spencer, R. W. (2018). Global Warming Skepticism for Busy People. Burke, VA: The Cornwall Alliance for the Stewardship of Creation.

Worsley, T. R. (1994). Phanerozoic CO2 levels and global temperatures inferred from changing paleogeography. In G. O. Klein, Pangea: Paleoclimate, Tectonics, and Sedimentation During Accretion, Zenith, and Breakup of a Supercontinent. Geological Society of America. doi:https://doi.org/10.1130/SPE288-p57

? 2019 Ronald S. Carson. All rights reserved.