The end of 2013 marked the first occasional observations of carbon dioxide levels in the atmosphere of 400 parts per million. There is nothing magical about that value, but we do tend to focus on round numbers.
We have heard the term “clean coal” for years, mostly from politicians and in coal company advertising. The concept sounds good: burn coal but don’t produce carbon dioxide emissions. While there have been various small-scale tests of technologies to accomplish this, it has not actually been a viable option for the power industry.
2015 was the hottest year in the historical record, easily breaking the mark set only one year earlier. The unusually large El Niño weather pattern is releasing enormous amounts of heat from the Pacific Ocean into the atmosphere, but climate scientists say that the bulk of the record-setting heat is due to the long-term warming effects of greenhouse gas emissions. The global land surface temperature was 1.6°F above the 20th century historical average. That’s a huge jump from 2014, which was 1.3° above average. That may sound like very little, but for the planet as a whole, it is extremely large.