by Michel de Rougemont
Not as naive as it seems, a related question was posed by Judith Curry on Twitter:
How much cloudiness varies will take into account 0.53 W/m2 increased TOA radiation since 2003?
https://twitter.com/curryja/status/1375144537522204672
She asked it regarding a recent article that was accepted for publication on Observational evidence of an increase in the global radiative force (Kramer et al., 2021).
Abstract. “Changes in atmospheric composition, such as increases in greenhouse gases, cause an initial radiative imbalance to the climate system, quantified as the instantaneous radiative force. This underlying metric is not directly observed globally and previous estimates come from models. This is partly because current space-based instruments cannot distinguish the instantaneous radiative force from the radiative response of the climate. We apply radiation nuclei to satellite observations to classify these components and find that the instantaneous radiative force of the entire sky has increased by 0.53 ± 0.11 W/m2 from 2003 to 2018, there was a positive trend in the planetary-wide radiation imbalance. This increase is due to a combination of increased concentrations of well-mixed greenhouse gases and a recent decrease in aerosol emissions. These results highlight distinct anthropogenic fingerprints in the Earth’s changing energy budget, which we found in observations to be detectable up to four years.”
This question touches on the heart of climate science because it cannot be an experimental science in which one can experiment with parameters in isolation from each other. Only a limited number of continuous instrumental observations and Paleolithic reconstructions can be used to attempt to distinguish natural processes from humans, especially radiation-induced processes. However, most of this work, if not all, takes place in silico.
The question can also be formulated in a more general way:
Is it possible, on a global scale and by instrumental observations, to distinguish the causes of a radiative forcing difference of 0.53 W?·m-2 over a period of 15 years?
For the cloud proposal:
- simple words, two-tier energy balance budget It can be estimated that, all else being equal, a 1% increase in cloudiness (about 66% overall) could cause a 0.54°C increase in temperature at the Earth’s surface and 0.45°C increase in temperature. °C at the top of the atmosphere (TOA)
- Regardless of any system feedback, radiated force 0.53 Wm-2 will increase the temperature 0.11°C at the surface and 0.18°C at TOA.
- To get the same temperature rise, thus to react with a force of 0.53 Wm–2it will change the cloudiness by 0.27% for the surface or 0.4% for the TOA.
- Is cloudiness, or variation in cloudiness, measurable with such precision and accuracy at an aggregated global scale? Is it 2003 and 2018?
From an overall energy balance point of view:
- Collectively, and for the sake of simplicity, modelers estimate all incoming and outgoing heat fluxes, and let any remaining heat warm or cool the oceans, thus reporting the called the ocean’s accumulated heat or “heat content anomalies”.
According to NASAfor the period 1993–2019, the anomalous heat flux from 0.36 to 0.41 Wm-2 for the first 700 m depth will be accumulated. Over time, other stages of heat release will also occur so the imbalance doesn’t allow us to boil or freeze forever (it never happens). - Over this 26-year period, this heat flux could imply a temperature change for a uniform 700-meter water column in the well of 0.10 to 0.11 °C, a change that is difficult to measure.
- A question, similar to the previous one, arises regarding instrumental observation: is it possible to measure such heat accumulation precisely, precisely, and at an aggregated global scale (by following local temperature monitoring or any other valid method)?
In all of these assessments, errors will have to be taken into account; those that arise from tool inaccuracies and inaccuracies, those that are embedded in the data massage (time and location-averaged), and those that are systematically derived from design incomplete and imperfect models, their parameterization and simplification.
In other words: the resulting balance sheet of any model must contain a junk account; but it also seems to be energy accumulating in the oceans. The Simple representations of NASA-Goddard do not show any; others (Trenberth, Fasullo, & Kiehl, 2009) show that the “actual absorption” is 0.9 W m-2 or US Global Change Research Program (USGCRP) says “Surface Unbalance” is 0.6 ± 0.17 W m-2 (one who appreciates margin accuracy). Taking into account all potential errors, however, the true range of effect of this imbalance could be hundreds of percent, thus challenging the story of a time bomb accumulating at the bottom of the ocean. positive.
One final question must be addressed for the climate science community: will the heat accumulated in the oceans ever be carried out by surface climate?
Presenter
Kramer, RJ, He, H., Soden, BJ, Oreopoulos, L., Myhre, G., Forster, PM, & Smith, CJ (2021). Observational evidence of global radiation intensification. Geophysical Research Letter, 48 (e2020GL091585). https://doi.org/10.1029/2020GL091585
Trenberth, KE, Fasullo, JT, & Kiehl, J. (2009). Earth’s Global Energy Budget.
Bulletin of the American Meteorological Society, 90 (3), 311–323. https://doi.org/10.1175/2008BAMS2634.1
Information about the Authors:
Michel de Rougemont, chemical engineer, PhD in technology, is an independent consultant. www.mr-int.ch
During his activities in fine chemicals and agriculture, he faces various environmental and safety challenges without fear.
He published a book’Réarmer la raison‘, sold at Amazonand a essay ‘Entre hysterie et negligence climatique‘ (both in French only).
He maintains a blog blog.mr-int.ch,, a website dedicated to climate climate.mr-int.chas well as biological control in agriculture biologicals.mr-int.ch
Email: [email protected]
He has no conflict of interest regarding the subject of this article.
