The uncertainty of science: Scientists are baffled by the sudden drop in one kind of atmospheric hydrochlorofluorocarbon (HCFC) gas that is thought to help create the hole in the ozone layer above the south pole.
New measurements show that after a rapid increase of the compound in the atmosphere of the Northern Hemisphere from 0.13 parts per trillion (ppt) in 2000 to 0.50 ppt in 2013, the concentration suddenly dropped to about 0.44 ppt by early 2015. This drop in concentration is equivalent to a 50 percent decline in global emissions percent of the gas: from 3,000 metric tons (3,300 US tons) in 2011 to about 1,500 metric tons (1,700 tons) in 2014, according to the new study.
Now for the kicker: They not only don’t know why this HCFC suddenly declined, they also don’t know where it is coming from. This gas is not one of the gases that were restricted decades ago to save the ozone hole. Until last year, scientists hadn’t even known it existed. And though the article claims it is human-caused, they haven’t yet identified how humans cause it. They hope its sudden decline in the atmosphere will help them pin down its source.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space
, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. The ebook can also be purchased direct from my ebook publisher, ebookit, in which case you don't support the big tech companies and I get a bigger cut much sooner.
Autographed printed copies are also available at discount directly from me (hardback $24.95; paperback $14.95). Just email me at zimmerman @ nasw dot org.