The CO2 Problem: Climate Models vs. Field Measurements

Abstract

Developed countries (e.g., USA, Germany, and France) have the unfair advantage over developing countries (e.g., Republic of the Congo, Republic of Kenya, and Sri Lanka) in imposing climate rules that enforce the use of expensive renewable energy based on flawed climate models with inflated CO₂ concentrations. This review attempts to bring attention to this irregular practice by amassing empirical data from field measurements on CO₂ that contradict climate models. The content is presented in two parts, (1) the “PhanDA” model and (2) the CO₂?1,000 ppm limit.

The “PhanDA” model-derived CO₂ value by Judd et al. (2024) for the Present is ~220 ppm, which does not match the measured value of 420 ppm at the Mauna Loa Observatory in Hawaii for the Present in the Keeling Curve. During the past 50 years, the Keeling Curve shows a rapidly increasing CO₂ trend, whereas the PhanDA model shows a rapidly decreasing trend.

Equally important, the PhanDA model is inapplicable for the Mesozoic era ((252 Ma-66 Ma), which represents 35% of the Phanerozoic eon (539 Ma-0). There is no correlation between Temperature and CO₂ during the Mesozoic, which is the underpinning of the model. Therefore, the PhanDA model and the associated assertion on the importance of CO₂ on Climate Change are problematic.

During a Trump-Musk Conversation on X (2024), Elon Musk claimed that when Atmospheric CO₂ goes past 1,000 ppm from the current value of nearly 400 ppm at a rate of 2 ppm per year increase, it would cause headaches and nausea in humans. This is a consequential claim to human health. In addressing this vital issue, a rigorous examination of 80,302 empirical data points from 25 countries on CO₂ concentration values available from direct measurements and from publications related to classrooms, conference rooms, dwellings, and aircraft cabins was carried out. This robust dataset (i.e., 46 figures and 13 tables) suggests that humans are able to function normally without adverse health effects even when CO₂ concentration levels reach between 2,000 and 6,000 ppm. Further, the U.S. Government (USDA, 2024) does not consider the CO₂?1,000 6limit as a health threat. In fact, the CO₂ 5,000 ppm is the U.S. Government’s Permissible Exposure Limit (PEL) of the daily workplace exposure. For basic physiological reasons, the concentration of CO₂ in ambient air is almost irrelevant as long as it is much smaller than about 40,000 ppm, where it is in equilibrium with the optimum CO₂ concentration of human blood. According to NRC (2007), 20,000 ppm is an appropriate sub chronic NOAEL (No Observed Adverse Effect Level) for headaches. Therefore, the notion that headaches supposedly associated with the 1.000 ppm limit of CO₂ is a fallacy. There is no need for concern about indoor CO₂ levels in classrooms, conference rooms, dwellings, and aircraft cabins.