The right release of OH to the troposphere with some modeling

Hydroxyl is the main sink for tropospheric ozone, which is desirable at this lower altitude but if we wanted to repair the ozone layer, we would need to ensure that oxide radicals were delivered to the stratosphere instead. The natural tendency of an oxide radical released at room temperature is to go to the ground state eventually if it does not form the newly termed doublet hydroxyl (An O* in HO*OH). This causes the oxide, or even a doublet hydroxyl radical to revert to HO2* or atomic ground state oxide, and then reincorporate into the Ozone cycle higher up, most likely in the Stratosphere. This would be most likely where the atmosphere is shorter, such as at the poles. This may be important if the Ozone Layer is now regularly damaged at both poles. (11-2020 Comment by Viva Cundliffe PhD abd)

Here the projection of atomic O making its way up towards the Stratosphere when dispersed.

Note this below explanation from this Harvard University site: The formulas are omitted here but are there


In the late 1950s it was discovered that catalytic cycles initiated by oxidation of water vapor could represent a significant sink for O3 in the stratosphere. Water vapor is supplied to the stratosphere by transport from the troposphere, and is also produced within the stratosphere by oxidation of CH4. Water vapor mixing ratios in the stratosphere are relatively uniform, in the range 3-5 ppmv. In the stratosphere, water vapor is oxidized by O(1D) produced from (R3) :

The high-energy O(1D) atoms are necessary to overcome the stability of the H2O molecule.

The hydroxyl radical OH produced by See can react with O3, producing the hydroperoxy radical HO2 which in turn reacts with O3:

We refer to the ensemble of OH and HO2 as the HOx chemical family. The sequence of reactions (R6) and (R7) consumes O3 while conserving HOx. Therefore HOx acts as a catalyst for O3 loss; production of one HOx molecule by (R5) can result in the loss of a large number of O3 molecules by cycling of HOx through (R6) and (R7) . Termination of the catalytic cycle requires loss of HOx by a reaction such as

The sequence (R5)  (R8) is a chain reaction for O3 loss in which (R5) is the initiation step, (R6)  (R7) are the propagation steps, and (R8) is the termination step. There are several variants to the HOx-catalyzed mechanism, involving reactions other than See  See ; see problem 10. 4 . From knowledge of stratospheric water vapor concentrations and rate constants for (R5)  (R8) , and assuming chemical steady state for the HOx radicals (a safe assumption in view of their short lifetimes), one can calculate the O3 loss rate. Such calculations conducted in the 1950s and 1960s found that HOx catalysis was a significant O3 sink but not sufficient to reconcile the chemical budget of O3. Nevertheless, the discovery of HOx catalysis introduced the important new idea that species present at trace levels in the stratosphere could trigger chain reactions destroying O3. This concept was to find its crowning application in subsequent work, as described below. Another key advance was the identification of (R5) as a source for the OH radical, a strong oxidant. As we will see in chapter 11, oxidation by OH provides the principal sink for a large number of species emitted in the atmosphere. Finally, recent work has shown that the HOx-catalyzed mechanism represents in fact the dominant sink of O3 in the lowest part of the stratosphere ( section 10.4 ). End Quote.

So, the two ongoing problems, Stratospheric Ozone decline, and Tropospheric swamping of hydroxyl levels due to anthropogenic pollution deserve different consideration for any direct remediation effort.

Viva Cundliffe, PhD abd

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