Photography, rowing and the pursuit of data.....and Renee  

Climate Change 

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Infra red emissions from warm bodies was first identified by Herscel in the 1850's. By the 1880, infra spectra had been measured.

 

In 1856, Eunice Foote had no PhD. No laboratory. No university appointment.  She had just discovered the greenhouse effect based on measuring the insulating properties of gases   Her paper, "Circumstances Affecting the Heat of the Sun's Rays,"  Three years later, in 1859, British physicist John Tyndall conducted similar experiments using more sophisticated equipment. He published his findings to acclaim and entered the history books as the discoverer of the greenhouse effect—the "father of climate science.

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Famously in 1902, Svante Arrhenius published a paper identifying the hazards of fossil fuel use, was picked up by the popular media. His critical observation was that carbon dioxide absorbs the infra red black body emissions from a 20C earth. 

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In 1970, the  Ventura 7 space mission to Venus, managed by the Russians, showed that the atmosphere is 97% carbon dioxide. The temperatures on Venus are 800C and are THE example of the effect of a runaway greenhouse gas atmosphere. 

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In 1988, James Hansen, then the director of the NASA Goddard Institute for Space Studies, stated to the U.S. Senate Energy committee “The greenhouse effect has been detected, and it is changing our climate now.” 

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​Immediate evidence

The Vostoc ice cores taken from Antarctica, show the carbon dioxide in the air tracking temperature through the ice ages, the second  graph shows the recent rapid increase in carbon dioxide way above previous concentrations since 1900.  

 

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By 2022, the impacts of climate change were affecting every corner of the earth through extreme weather and changes in the distribution of water. For example, major rivers are drying out, glaciers disappearing, along with  massive floods.

 

 

 

 

 

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The measured greenhouse effect shown in the graph on the left is around 1C per 100 ppm in CO2, in spectacular agreement with Arrhenius's original estimate of 1.3C​

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In 2025, temperature rise over 1880 baseline is 1.5C, CO2 422 ppm compared to 275 ppm in pre- industry and last Ice Age cycle warming maximum. Sea level rise 0.3m  (7") in 2020. Ice pack tracks the seasons so surface melt has a >1 year time constant. 

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The effect of carbon dioxide on temperature takes around 500 years to reach equilibrium, with an additional 1-1.5C over the "immediate" impact.   

https://archive.ipcc.ch/ipccreports/tar/wg1/345.htm

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​Long term history 

The effect on the equilibrium sea level can be estimated based on what happened 100M years ago in the time of the dinosaurs. Carbon dioxide was 700ppm above current levels, temperatures were 10C higher, there were no ice caps and sea levels were a stunning 100m (330 ft) higher than today. 

NASA climate database 

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There is now a much more complete historical record back to 60 M years ago, that shows the equilibrium sea levels. 

The sea level record back to 800,000 years ago -  Spratt, R. M. and Lisiecki, L. E.: A Late Pleistocene sea level stack, Clim. Past, 12, 1079–1092, https://doi.org/10.5194/cp-12-1079-2016, 2016.

Back to 60M years ago; Ancient Sea Level as Key to the Future By Kenneth G. Miller et al doi.org/10.5670/oceanog.2020.224

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The current projections suggest that by 2100, there could be a 5C  increase in temperature, and a +1.2m  rise in sea level.

 https://www.livescience.com/39891-sea-level-rise-ipcc-report.html

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Over 100 years, 5C temp increase, the equilibrium contribution would be 1m which  is enough to possibly double rise in 2100. Collapse of any land based ice shelf would create a much larger step change. 

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It is important to note that the timescale for reaching equilibrium in temperature in our projection is on the order of thousands of years, far beyond most policy-relevant climate. projections.  https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025AV001719

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 CO2 data; Foster, G., Royer, D. & Lunt, D. Future climate forcing potentially without precedent in the last 420 million years. Nat Commun 8, 14845 (2017). https://doi.org/10.1038/ncomms14845

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Temperature data; https://en.wikipedia.org/wiki/File:All_palaeotemps.png#Summary

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The ice ages are linked to orbital changes that produce a 20% change in solar warming.   

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Currently the heating effect of extra greenhouse gases, since the start of the industrial revolution, from the mid 1700s to the mid 1800s, is equal to about one watt per square meter (0.3%) for 100 ppm CO2.  averaged over the year and the day, the Earth's atmosphere receives 340 W/m2 from the Sun. 

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If all the ice covering Antarctica, Greenland, (Antarctica would make about 60 meters of sea-level rise, Greenland about 7.4 meters), and in mountain ice caps around the globe were to melt, sea level would rise about 70 meters (230 feet) and cover all seaside cities.

https://vividmaps.com/the-world-with-a-70-meters-sea-level-rise/

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Antarctic ice sheet weighs 24,380,000 gigatons, that is being lost at  40 ± 9 Gt/y from 1979 to 1990, 50 ± 14 Gt/y from 1989 to 2000, 166 ±18 Gt/y from 1999 to 2009 and finally 252 ±26 Gt/y from 2009 to 2017 for a roughly 1C rise. 

https://en.wikipedia.org/wiki/Antarctic_ice_sheet

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A simple linear extrapolation can estimate time to melting all the ice.  Sea level rise since 1880, 0.3m with 1.5C temp change, and 420-290 = 130 ppm CO2 level.  Effectively 1C for every 100ppm, consistent with Arrhenius' estimate in 1901.  

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The Earth has cycled from ice free to iceberg on multiple occasions. Most recent ice free cycle was associated with volcanic activity, that increased CO2 levels to 1000ppm, eliminating ice. Subsequently CO2 has decreased to 300ppm, temperatures decreased by  12C and  sea levels have dropped by 100m.   In the last 800K years, ice age cycles have produced periods with temperature changes of 8C and  additional 100 m of sea level drop. 

 

To date, over 100 years CO2 has increased 150ppm, average temperatures 1.5 C, and sea levels have risen 0.3m. At thermal equilibrium, linear extrapolation  suggests that a 1.5C rise should produce 15m of sea level change over 5,000 years.  These linear predictions will probably be overwhelmed by irreversible "tipping points" such as the collapse of the Gulf Stream

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Paleo climate data suggest ice melting in roughly 7,000 years .

https://www.igminresearch.com/articles/a-pdf/igmin239.pdf

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"In the cooling case, the time to achieve 70% of the equilibrium response in the midoceanic depths is about 500–1000 yr. In the warming case, this response time is 1300–1700 yr" - Time Scales of Climate Response by RONALD J. STOUFFER.​. 

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By 2100, current IPCC estimate is 3.0C +-1.0C. There will be a 2x increase in extreme events compared to today. ​​​
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In the short term it is estimated that by 2100 the rise could be 0.6m,  These sea levels will impact most sea edge cities in the world. The time scales emphasize that the changes we have seen already are nothing compared to what will happen as we reach equilibrium, and also how long it will take for the changes that we must make will have an impact. 

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The use of fossil fuels since the industrial revolution has pumped enough Carbon Dioxide into the atmosphere to change the planet. To date, over 100 years CO2 has increased 150ppm, average temperatures 1.5 C, and sea levels have risen 0.3m. At thermal equilibrium, linear extrapolation  suggests that if it stays at only a 1.5C rise there will be 15m of sea level rise over 5,000 years.  Unfortunately CO2 is still increasing.   If the ice caps disappear eventually there will be 100m of sea level rise - Austin is beach front.

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Tipping points

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Disruption of the earth currents are probably one of the most significant tipping point. The Atlantic Meridional Overturning Circulation (AMOC) carries warm water north from the Southern Hemisphere, where it releases heat and freezes. The freezing process concentrates salt in the non-frozen portion of the ocean water; this extra-saline water sinks, travels back south and picks up heat again, restarting the conveyor belt. (The Gulf Stream is part of this belt.) This release of heat helps keep Europe, and to some extent North America, balmier than it otherwise would be. But sediment records over the past 100,000 years suggest that, at times, the AMOC has shut down abruptly, leading to major climate shifts over mere decades.  If the AMOC were to collapse in the near future, the consequences would be dire. Without the AMOC, the Northern Hemisphere would get colder, and the southern hemisphere would get warmer, though by a lesser degree . The effects vary by region, but Europe would be hard hit, van Westen said, cooling between 9 and 18 degrees Fahrenheit (5 to 10 degrees Celsius) within a century. That's a huge swing, even compared with the current level of climate change, which is already having impacts. 

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Without global warming, the earth is at a high temperature, low ice point in the last 400K years of ice age cycles. Loosing the polar ice will take us back to conditions that have not existed for 60M years. If/when the AMOC shuts off, Europe will initially cool and annual weather cycles will be disrupted. Then the global heating will take over and continue to melt. 

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AMOC strength has decreased by a few Sverdrups (1 Sv = 1E6 m3 s−1) from 2004 to 2012, from around 17 Sv. Longer timescale variability of the AMOC strength, estimated by using sea surface temperature (SST) time series based on “fingerprint” patterns (4), indicates that the AMOC weakened by 3 ± 1 Sv since about 1950. From proxy records, it has been suggested that the AMOC is currently in its weakest state in over a millennium (5).

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Modelling suggests that collapse occurs at around 10 Sv, a drop of 40%. Patchy historical data suggests AMO dropping at  15% in 50 years, suggesting another 100 years before disaster. 

https://www.science.org/doi/10.1126/sciadv.adk1189

https://en.wikipedia.org/wiki/Atlantic_meridional_overturning_circulation​​

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Tipping points are associated with the melting of various ice regions. Wide variation in guesses, 1-10k years for most major ice fields to disappear. 

https://climatetippingpoints.info/2022/09/09/climate-tipping-points-reassessment-explainer/

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Costs of energy generation 

My experience with Total Cost of Ownership models in a different (semiconductor) arena is that its very hard to distill them into actions.  I think I understood that ERCOT buys based on the self accessed cost of ownership of the independent generating company. One approach is apply a cost correction weighting factor to the generators bid in weighing choices. 

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My second take away was that the minimum gas generation capacity is determined by grid stability not economics or carbon emissions, and I would assume that min and max solar to wind ratio is also bounded by stability concerns. TCO really applies in optimizing the ratio of solar to wind within these limits. 

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My third take away is that carbon capture from the minimum gas capacity is essential.

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Fourth takeaway is that the costs of ecological damage from both climate change and extraction pollution probably dwarf all other costs and are very difficult to bound. However at least extraction pollution is mitigatable. 

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