Stratosphere the stratosphere temperatures increase with altitude "(see temperature inversion)"; the top of the stratosphere has a temperature of about 270 K (−3°C or 26.6°F). This vertical stratification, with warmer layers above and cooler layers below, makes the stratosphere dynamically stable: there is no regular convection and associated turbulence in this part of the atmosphere. However, exceptionally energetic convection processes, such as volcanic eruption columns and overshooting tops in severe supercell thunderstorms, may carry convection into the stratosphere on a very local and temporary basis. Overall the attenuation of solar UV at wavelengths that damage DNA by the ozone layer allows
Exposing Microorganisms in the Stratosphere stratosphere (31 km above sea level), 99.9% of the entire population was destroyed. According to the researchers, "most terrestrial bacteria would be inactivated within the first [day] on Mars if contaminated spacecraft surfaces receive direct sunlight." Of the 40 million spores exposed to the stratosphere, only 267 spores (or 0.0007%) remained viable. Extrapolating this, no viable spores would remain if flight samples had an additional 150 minutes of Sun exposure in the stratosphere (630 min total time). The survivors showed three single nucleotide (base pair) substitutions compared to unexposed controls kept on the ground. These three coding regions are associated