Jenna Ladd | October 25, 2016
With carbon dioxide in the atmosphere reaching 400 parts per million (ppm), the World Meteorological Organization (WMO) recently announced that a new era of “climate change reality” has begun.
Earth’s atmosphere contained 400 molecules of CO2 for every one million molecules for the first time in globally recorded history in 2015, and 2016 is likely to be the first year where global averages exceed this threshold.
Even though human outputs of CO2 remained steady from 2014 through 2015, a particularly strong El Niño in 2015 caused a dramatic increase in greenhouse gas levels. El Niño is a weather phenomenon characterized by especially warm temperatures in the Equatorial Pacific Ocean that have far-reaching weather effects. In 2015, the phenomenon caused drought in tropical regions around the globe, which negatively affected the amount of gases that forests, vegetation, and oceans were able to absorb.
While El Niño heightened the spike of greenhouse gases in the atmosphere last year, human activities like agriculture and industry caused 37 percent of the warming effect due to methane, carbon dioxide, and nitrous oxide increase from 1990 through 2015. Petteri Taalas, WMO secretary-general, said, “The El Niño event has disappeared. Climate change has not.” Scientists at the longest-running greenhouse gas monitoring station in the world in Hawaii say that CO2 levels will not drop below 400 ppm for several generations. Carbon dioxide is responsible for around two-thirds of the warming effect that long-lived greenhouse gases have on the atmosphere.
WMO released this report just before the next round of climate talks associated with the Paris Agreement, a climate change mitigation plan signed by 200 nations last December. Participating countries committed to limiting temperature increases to less than 2 degrees Celsius above pre-industrial levels.
Taalas said, “The year 2015 ushered in a new era of optimism and climate action with the Paris climate change agreement. But it will also make history as marking a new era of climate change reality with record high greenhouse gas concentrations.”
The 200 nations will meet in Morocco next month to forge a path forward.