Eighty-five percent of the Earth's air resides in the lowest layer of its atmosphere, or troposphere. Yet, major gaps remain in our understanding of the atmospheric chemistry that drives changes ...

TONIGHT: Overnight lows cool to the upper 30s with winds out of the northwest at 5-10 mph and gusts up to 15 mph possible.

The tropopause is defined as the upper limit of the troposphere which is the lowest layer of the atmosphere. A new study shows the earth’s atmosphere is expanding due to climate change.