Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Perspective of changes in O3 concentration resulting from estimated 2010–2015 emission changes over (top panels) the US and (bottom panels) east Asia at the (a) surface, (b) bottom of free troposphere (750hPa), (c) middle of free troposphere (500hPa), and (d) top of free troposphere (250hPa).
