CO2 levels rose to nearly 398 parts per million, from 396 ppm in 2013, the World Meteorological Organization said.
The CO2 level fluctuates throughout the year and the monthly average crossed the symbolic 400 ppm threshold in March 2015. The WMO said the annual average "is likely to pass 400 ppm in 2016."
Pushed by the burning of coal, oil and gas for energy, global CO2 levels are now 143 per cent higher than before the industrial revolution. Scientists say that's the main driver of global warming.
"Every year we report a new record in greenhouse gas concentrations," WMO Secretary-General Michel Jarraud said. "We have to act now to slash greenhouse gas emissions if we are to have a chance to keep the increase in temperatures to manageable levels."
World governments are meeting in Paris later this month to craft a new UN pact to rein in greenhouse gas emissions.
Meanwhile, climate change is already transforming the Earth, melting Arctic sea ice, intensifying heat waves, and warming and acidifying the ocean.
Climate scientists say that if global warming continues unabated, dangerous effects could include flooding of coastal cities and island nations, disruptions to agriculture and drinking water, and the spread of diseases and the extinction of species.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
