IN 1800, CO2 levels were about 283 parts per million and by 1912 about 301ppm – look it up.
By 1989 CO2 levels had reached Dr Hansen’s so-called safe level of 350ppm.
IN 1800, CO2 levels were about 283 parts per million and by 1912 about 301ppm – look it up.
By 1989 CO2 levels had reached Dr Hansen’s so-called safe level of 350ppm.