What temperature, pressure, and water vapor concentration would you expect to see in the
stratopause?

The expected parameters in Stratopause are; Temperature: -15 degrees Celsius, Pressure: 1 milibar and Water vapor concentration: cannot be determined.

Explanation:

"Stratopause" is the interaction between the ionosphere and the stratosphere. It is 50-55 km high above the earth surface that is why temperature is very less approximately -15 degrees Celsius (5 degrees Fahrenheit). As it is a thin layer separating the stratosphere and ionosphere actual water vapor concentration cannot be determined. The atmospheric pressure is around 1/1000 of the pressure at sea level.

fire could start, buildings collapsing, and ash falling from the sky.

explanation:

this is because the buildings or plants could catch on fire and the buildings would most likely collapse. lastly ash would fall because all the burning would cause ash to fall from the sky.

hope this .