Noctilucent Clouds

Noctilucent Clouds(NLCs) are high-altitude wispy-like clouds formed from ice crystals within the mesosphere at ~80km. Sometimes referred to as polar mesospheric clouds, NLCs are observed on the horizon at mid lattitudes around dusk when solar illuminated from below. No observations of NLCs exist prior to 1885 - NLCs are considered harbingers of climate change resulting from the presence of increased atmospheric methane.

NGDC paper archives include a number of reports and original paper records of NLC observations from the late 1960's through the early 1980's.

Data Documentation: