FIG. 4.
(Color online) Spectral probability density plots for the month of February 2019. The 10th, 50th, and 90th percentile curves are overlaid.
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.