Wolkenvormen zijn uitdrukkingen van het onderliggende landschap, grote fenomenen en soms lokale menselijke activiteiten.
“Ook komt de Wereld Meteorologische Organisatie (WMO) met
een aanduiding voor wolken zoals vliegtuigstrepen die door menselijke
activiteit zijn ontstaan: 'homogenitus', ofwel 'door de mens gemaakt'.”
Ik lees ondermeer over deze menselijk beinvloede wolken:
“2.2.2. Anthropogenic clouds
2.2.2.1. In a
paper [Reference 3] "Clouds
caused by human activities", published in the Royal Meteorological
Society's journal 'Weather' in November 2012 (Volume 67:11), J. Mazon, M.
Costa, D. Pinto and J. Lorente proposed that clouds clearly arising from human
activity should be designated with the prefix 'anthropo-'/(a) to differentiate
them from clouds of natural origin. In the case of aircraft condensation trails
(contrails) spreading out into cirri-form clouds, the author's proposed that
these anthropogenic clouds (anthropo-clouds) should be classified as:
anthropoCirrus (aCi), anthropoCirrocumulus (aCc) and anthropoCirrostratus
(aCs). In their paper, Mazon et al also consider other examples of clouds
produced by human activities, such as anthropoCumulus and anthropoStratus .
2.2.2.2. The Task Team accepted that there was a case
for the specific classification of clouds caused by human activities. The prime
example being that of aircraft condensation trails (contrails). It is well
known that in certain atmospheric conditions contrails may persist and, with
time, these may then spread under the influence of the upper winds to cover
large parts of the sky in cirriform clouds.
2.2.2.3.
The current ICA states: -
II.6.3
Condensation trails (contrails)
Contrails are clouds which form in the wake
of an aircraft when the atmosphere at flying level
is sufficiently cold and humid. When just
formed, they have the appearance of brilliant white
streaks; soon however they show pendant
swellings like inverted mushrooms. Often they are
short-lived, but especially when Cirrus or
Cirrostratus is present, they may persist for several hours.
Persistent trails spread progressively,
frequently forming large patches of fluffy or fibrous clouds,
having the appearance of Cirrus or patches
of Cirrocumulus or Cirrostratus; in fact it is sometimes
impossible to distinguish old contrails from
these clouds.
II
.6.7 PART II - 6. SPECIAL CLOUDS
Clouds
resulting from industry
These
clouds have very diverse origins; the following are mentioned only as examples:
clouds
of
smoke and steam in industrial areas, smoke clouds created for frost protection
purposes, clouds
of
insecticide gas or powders in agricultural areas.
II
.6.8
Clouds
resulting from explosions
When
an explosion is very large, it is usually accompanied by a cloud of smoke and
dust.
Above
this cloud, velum or pileus are often seen. Sometimes the propagation of shock
waves is
manifested
by dark rings or bands moving with extreme rapidity.
2.2.2.4. The
Task Team noted that the prefix 'anthropo-' is derived from the Greek word for man-made and expressed the view that
it would not be desirable to mix Greek with Latin in the cloud classification
scheme. Also the cloud classification scheme utilises suffixes for
'mother-cloud s, rather than prefixes, as per the following sections from the
ICA:-“
