Figure 4.
Probability density functions (PDFs) of the GEM data (ng m−3) for the northern, southern and tropical sample groups (dash dotted lines). Full lines the normal distribution fit of the samples.
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.