Archive for September, 2018

UVI and total ozone column: 3 days in September 2018

September 27, 2018

I wrote many times on the relationship between the total thickness of the ozone layer(TOC) and the UVB radiation at ground level (see paper, and comments here, here. Roughly speaking, the ozone column is a filter for UVB, so when this filter becomes thinner (the measure of TOC gives decreasing Dobson units), the UVB irradiance should increase. One common relationship to quantify this increase is the radiation amplification factor RAF defined by RAF = -[ln(DU1/DU0)]/[ln(TOC1/TOC0)].

Today and the two previous days (27, 26, 25 Sep.2018) gives a nice illustration.

First note that the maximum of the total solar irradiance was more or less constant, whereas the UVB irradiance increases markedly:


The next plot shows the variation of the UVI (UV index, here UVI = 0.00278*UVB when UVB is given in mMED/h):


The TOC numbers are given in DU below the x-axis: they decrease from 267 to 227. A quick X/Y graph shows a possible linear relation-ship:

From the 25th to the 27th September, a TOC decrease by 17% causes an increase of the UVI by 14% (please note that the relationship is logarithmic, so this line should seen as a linear approximated segment of the “real” curve).

Using the RAF formula given above for the second and last days and replacing the DU readings by DU/cos(SZA) as stated in the paper yields an average RAF of 1.086, close to the values found in the paper

Conclusion: our measurement clearly show the inverse relation-ship between TOC and UVB irradiance.



29 Sep 2018:
changed calculation of RAF’s by using “slanted” formula given in the paper (DU replaced by DU/cos(SZA)) and calculating the RAF’s for the second and third day by taking the 25th September as base-line (index 0 in the formula)


Stop this energy transition!

September 23, 2018

Laurent Alexandre, a well known urologist and company founder (former director of Doctissimo) has a very interesting and clear article in the French weekly L’Express, one of the oldest and most read French news weeklies. L’Express usually is left and green leaning, so this article (“Arrêtons cette transition énergétique“) which speaks clearly against the official French energy politics is remarkable.

L. Alexandre writes that the ecologists work (often through ignorance) to increase CO2 and fine particle emissions. The French greens, as most of their European partners and the multi-billion lobby Greenpeace, are strongly anti-nuclear, and stubbornly ignore that France is a world-champion in low-CO2 electricity production. The following picture from shows the live CO2 intensity of electricity production for a large part of the EU (the picture corresponds to 23 Sep. 2018, 11:300 UTC):


Clearly France with its more than 75% nuclear electricity is the winner, by a very large margin. The 32 g must be compared to the “über-grün” Germany situation of 339 g. Germany’s part of renewables is 42%, France’s is 27%. Germany has a breathtaking 105000 MW wind and solar installed capacity, France’s nuclear capacity is only 63000 MW.  This much lower nuclear capacity produces 400 TWh CO2 free and reliable electricity a year, whereas Germany’s 167% higher renewables (at a cost > 200 billion €) do not generate more than 140 TWh intermittent energy a year.

Alexandre has this biting sentence: “L’affreuse réalité, c’est que, aujourd’hui encore, les énergies intermittentes ne sont vertes que quelques heures par jour et sont indirectement des énergies noires la plupart du temps..” which translates into “the frightful reality is that today the intermittent energy sources are green only for a couple of hours per day, and indirectly black for most of the time..”

An he concludes by “Vous serez fascinés par notre bêtise collective… alimentée par une stratégie de communication mali(g)ne des industriels “verts”. Les ayatollahs verts veulent nous amener dans l’impasse allemande…” (you should be fascinated by our collective imbecility…which is fostered by the evil communication of the green industrial lobby. The green ayatollahs would like to push us into the German dead-end…”).

Is this comment published in the Express a sign that some EU media do not sheepishly echo anymore anything written in green?


h.t. to René T. for pointing me to this article.