Do emissions from severe fires influence the formation of noctilucent clouds?

This paper presents analysis of photographs of noctilucent clouds taken on June 30, 2021, over the central part of Yakutia. They were distinguished by their brightness and shape in the form of blurred elongated parallel stripes of haze and many clear waves perpendicular to them. These waves on the clouds demonstrate a "trace" from the propagation of internal gravity waves from the lower layers of the atmosphere to the upper ones. The conditions for the formation and observation of noctilucent clouds are described. Based on Aura MLS satellite data on moisture content and mesopause temperature, the freezing temperature of water vapor was calculated. The increasing frequency of detection of noctilucent clouds is associated with an increase in the concentration of methane in the atmosphere. One of the powerful sources of greenhouse gas emissions is biomass combustion. In the summer of 2021 in Yakutia, extremely strong forest fires were observed over the past four decades. This is evidenced by the active fire data from MODIS and VIIRS sensors. The question arose: "Do emissions from severe fires affect the formation of noctilucent clouds?" For this purpose, methane concentration distribution maps were constructed based on AIRS data, with wind fields from NCEP/NCAR reanalysis data. A strong anticyclone at the end of July 2021 contributed to intensification of forest fires and significant increase in the methane content in the atmosphere in central Yakutia. Such meteorological conditions and the propagation of internal gravity waves could have affected the vertical transport of methane molecules, which likely were transformed into water molecules during chemical reactions in the stratosphere. An increase in the moisture content of the mesosphere could have been one of the components of the cause of the formation of bright noctilucent clouds on June 30, 2021.