How much sky coverage is “significant?”

By davedahl, May 26, 2015

When I speak with scientists– especially climatologists, meteorologists and chemists– they believe that “aircraft clouds affect the weather” or NASA’s statement that “the abundance and location of clouds” would effect the climate more than CO2 or other green house gases, but many still think the impact of jet aircraft and artificial clouds on the climate is trivial (even though they don’t know how much would not be trivial).

I disagree. I think the impact on the weather and climate is evident and far from trivial.

Today is a good example. As you can see from this photo taken about five minutes ago, jet-spawned clouds are covering a substantial part of the sky.

The thinnest contrail in the middle was made about sixty seconds before taking this photo; and the thickest one below it, made about fifteen minutes ago, is expanding and already on its way to becoming a cloud, having hardly appeared to move at all.

So how much is significant? Today, it’s significant: it’s cloudy when it would otherwise be sunny. How can we tell? We watch these contrails become clouds and create shade here below.

When clouds obscure the sun in a large area like this, they create a shady area below in which the temperature drops.

The drop in temperature makes the air in the shaded area contract, dropping the pressure and creating wind as a result of the pressure difference.

So today, we have clouds and shade instead of sun. This is due to water moisture from jet air traffic (about 10 trillion cubic feet per year) mixing with natural (ice crystal saturation) and artificial (cloud seeding material)  condensation nuclei combining to produce clouds.

When the rain comes, the cloud seeding material and the artificial clouds have accelerated the storm and made the clouds thicker.

I’d call that a significant weather change too, so Yes, I’d say that by introducing massive quantities of artificial condensation nuclei the upper atmosphere via weather modification programs, we’re changing the weather signifiicantly.

More about weather modification and artificial clouds