noctilucent cheshire

Cheshire, UK. Photo Lee Taylor
An amazing outbreak of Noctilucent Clouds occurred across Europe this month of June with displays reported on June 8th, 10th and 11th, with a major display on the night of June 12/13th and another one on June 17/18th. June 21st however was perhaps a record breaking display with NLCs reported in literally dozens of countries.

Another remarkable aspect of the recent displays is that in many locations the clouds were seen across half the sky. NLCs are usually only seen in the northern part of the sky.

The highest clouds in Earth's atmosphere, noctilucent clouds are actually cloud-like formations made of ice-crystals that form in the mesosphere at altitudes of around 76 to 85 km. The increase in observations in recent years suggest a cooling of the mesosphere. They are most often observed during the summer months from latitudes between 50° and 70° north and south of the Equator. They are visible only during local summer months and when the Sun is below the observer's horizon, but while the clouds are still in sunlight. Recent studies suggest that increased atmospheric methane emissions produce additional water vapor once the methane molecules reach the mesosphere - creating, or reinforcing existing noctilucent clouds.

Over the next few weeks, watch the northern skies in evening and morning twilight. Noctilucent clouds will be bright white or bluish, while other clouds (lower down in the troposphere) will be already dark. Noctilucent clouds come in many different shapes and forms, from tenuous veils, to long streaking, parallel bands, closely spaced waves and ripples and sometimes even whirls.

noctilucent west yorkshire

West Yorkshire, UK. Photo: Curtis Thackray
Noctilucent cloud

Bavaria, Germany. Photo: Josef Zeitler‎‎‎.
noctilucent cheshire

Cheshire, UK. Photo: Lee Taylor
noctilucent czech republic

Němčice, Czech Republic. Photo: Jitka Rösslerová‎‎‎‎‎.
noctilucent edinburgh

Edinburgh, UK. Photo: Aldo Marchesi‎.
noctilucent netherlands

Groningen, the Netherlands. Note the reddish color of the upper part of NLCs – this part is illuminated by the evening reds refracting through the atmosphere. Photo: Dennis Veninga‎‎.