Chemical Composition of the Middle Atmosphere and Its Changes in the 21st Century

• Published in: Russian journal of physical chemistry. B Vol. 12; no. 6; pp. 1094 - 1098
• Main Author: Larin, I. K.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-11-2018; Springer Nature B.V
• Subjects: 21st century; Carbon tetrachloride; Chemical composition; Chemical Physics of Atmospheric Phenomena; Chemistry; Chemistry and Materials Science; Chlorofluorocarbons; Hydrochlorofluorocarbons; Hydrogen peroxide; Initial conditions; Mesosphere; Middle atmosphere; Nitrogen dioxide; Organic chemistry; Physical Chemistry; Stratosphere; Trace gases; Troposphere; Two dimensional models; mesosphere; chemical families; troposphere; trace gases; stratosphere
• ISSN: 1990-7931; 1990-7923
• DOI: 10.1134/S1990793118060064

The chemical composition of the middle atmosphere (composed of the troposphere, stratosphere, and mesosphere) and its changes in the 21st century are considered. The initial data were obtained from the interactive two-dimensional radiation–chemical model SOCRATES, which calculates the height profiles of components with a resolution of 1 km in the latitudinal zone from 85° S to 85° N, with a step of 5°. The initial conditions were taken to be the Intergovernmental Panel on Climate Change (IPCC) RCP 4.5 scenario for June and January of 2000 and 2100 at a latitude of 50° N. For these conditions, the height profiles and the total content of the long-lived components N
2
O, CH
4
, and CO
2
; chlorofluorocarbons (CFCs) CFC-10 (CCl
4
), CFC-11 (CCl
3
F), CFC-12 (CCl
2
F
2
), CFC-113 (CCl
2
FCClF
2
), CFC-114 (CClF
2
CClF
2
), CFC-115 (CClF
2
CF
3
), halon-2011 (CBrClF
2
), and halon-1301 (CBrF
3
), hydrochlorofluorocarbon (HCFC) HCFC-22 (CHClF
2
); acids HF, HCl, HBr, and HNO
3
; atmospheric trace gases O(
3
P), O(1D), H, OH, HO
2
, H
2
O
2
, Cl, Cl
2
, ClO, OClO, HOCl, ClONO
2
, ClNO
2
, Cl
2
O
2
, N, NO, NO
2
, NO
3
, N
2
O
5
, HO
2
NO
2
, Br, BrO, HOBr, BrONO
2
, and BrCl, as well as the chemical families O
x
(O
2
+ O(
3
P)), HO
x
(OH + HO
2
), NO
x
(NO + NO
2
+ NO
3
), ClO
x
(Cl + ClO), and BrO
x
(Br + BrO). Among other conclusions, it has been shown that for June 2100, the relative change (in %) in the total content of components in the ClO
x
, O
x
, BrO
x
, NO
x
, and HO
x
families in the stratosphere, in comparison with June 2000, would be–57.5%, +4.0%,–25.7%,–13.9%, and–4.1%, respectively. For January, the corresponding values for ClO
x
, O
x
, BrO
x
, NO
x
, and HO
x
are–59.1%, +7.3%,–26.2%,–7.1%, and–3.6%, respectively. Similar comparisons have been made for the other components mentioned above. Almost all chemically active components are highly sensitive to the season change.