Dec. 9, 1921:  Chemist Thomas Midgley, Jr. discovers that adding Tetraethyl Lead (TEL) to gasoline reduces engine knock and increases performance.  Decades later, leaded gasoline would be banned for its impacts on human health.

Dec. 9, 1952:  A deadly fog finally lifts over London. As many as 12,000 may have died from the mixed impacts of weather, smog, and factory pollution.

Dec. 9, 2005:  A fierce winter storm is blamed for the stranding of nine pilot whales and 24 common dolphins in Cape Cod Bay.   None of the animals survive.

Dec. 9, 2012:  Another U.N. climate conference ends in Doha, Qatar.  Delegates and observers bemoan the meeting’s failure to produce any agreements on greenhouse gas emissions.

Photo: Steve Snodgrass/Flickr

This feature is compiled by Peter Dykstra, an MNN contributor and publisher of Environmental Health News and The Daily Climate.