Color blindness all variations in human color vision involve the red and green receptors in male eyes. It is very rare for males or females to be "blind" to the blue end of the spectrum. The first scientific paper on the subject of color blindness, "Extraordinary facts relating to the vision of colours", was published by the English chemist John Dalton in 1798 after the realization of his own color blindness. Because of Dalton's work, the general condition has been called "daltonism", although in English this term is now used only for deuteranopia. Color codes present particular problems for those with color
Scientific opinion on climate change researchers unconvinced of ACC are substantially below that of the convinced researchers. A 2013 paper in Environmental Research Letters reviewed 11,944 abstracts of scientific papers matching "global warming" or "global climate change". They found 4,014 which discussed the cause of recent global warming, and of these "97.1% endorsed the consensus position that humans are causing global warming". This study was criticised by Richard Tol. James L. Powell, a former member of the National Science Board and current executive director of the National Physical Science Consortium, analyzed published research on global warming and climate change between 1991 and 2012 and found