Four hundred: it’s a number that will go down in climate history while also continuing to rise.
According to the National Oceanic and Atmospheric Administration (NOAA), 400.83 parts per million (ppm) was the average concentration of atmospheric carbon dioxide in March. This news from NOAA marks the first time that the entire planet has surpassed the 400 ppm benchmark for an entire month.
Last month was the warmest June since records began being kept in 1880, the National Oceanic and Atmospheric Administration (NOAA) reported Monday. That follows the warmest May on record.
Last month broke a temperature record, averaging 59.93 degrees Fahrenheit — a degree and a third (1.33°F) above the 20th century baseline, according to new data released Monday by the National Oceanic and Atmospheric Administration. May 2014 was the 39th consecutive May that was warmer than average. This was also the 351st consecutive month where the global temperature was hotter than the 20th century average, meaning if you are 29 years old, you have never experienced a colder-than-average month in your life.