Perhaps the BEST B1G Forum anywhere, here at College Football Fan Site, CFB51!!!

A US patent today, FYI, expires twenty years after date of filing.  The rule changed some time back from 17 years from date of issue to 20 from date of filing.

Once expired, the technology is open for use by anyone.  And you're "supposed" to reveal everything you know about the invention to enable someone else to practice it.

I would have to do some research, but too lazy right now.  I seem to remember reading an article in some business journal that stated the patent expired in 1979.  I would assume at this point that Dupont did some modification to extend their patent(s) to get to 1979.

Earth heats up due to pandemic’s cleaner air, study finds

https://fox8.com/news/earth-heats-up-due-to-pandemics-cleaner-air-study-finds/

The study states:

“The COVID-19 pandemic changed emissions of gases and particulates. These gases and particulates affect climate. In general, human emissions of particles cool the planet by scattering away sunlight in the clear sky and by making clouds brighter to reflect sunlight away from the earth. This paper focuses on understanding how changes to emissions of particulates (aerosols) affect climate. We use estimates of emissions changes for 2020 in two climate models to simulate the impacts of the COVID-19 induced emission changes. We tightly constrain the models by forcing the winds to match observed winds for 2020. COVID-19 induced lockdowns led to reductions in aerosol and precursor emissions, chiefly soot or black carbon and sulfate (SO4). This is found to reduce the human caused aerosol cooling: creating a small net warming effect on the earth in spring 2020. Changes in cloud properties are smaller than observed changes during 2020. The impact of these changes on regional land surface temperature is small (maximum +0.3K). The impact of aerosol changes on global surface temperature is very small and lasts over several years. However, the aerosol changes are the largest contribution to COVID-19 affected emissions induced radiative forcing and temperature changes, larger than ozone, CO2 and contrail effects.”

So the smog actually protects the earth from the evil sun?

Kinda like back in the Dark Ages, when a good thick layer of crusty dirt on your skin, was thought to protect you from illness?

great smog both increases and decreases global warming

I understand perfectly

Kinda like back in the Dark Ages, when a good thick layer of crusty dirt on your skin, was thought to protect you from illness?

Wimanz pay good coin for mud packs

The cause, and scope, of the Little Ice Age remains a mystery.  Some suggest the sun went into a period of reduced activity.

Some claim it only happened in the northern hemisphere.  Some claim it was due to a volcanic eruption (for 300 years?).

so, why wasn't the earth warmer 100 years ago, before the 2nd industrial revolution?

How much of human activity centered around burning wood in those days? For heat, for cooking, etc? Burning logs creates plenty of particulate matter. 

seems to me that you folks in California have been burning too much weed lately

There, fixed that for you.