During the Conference of Parties in Paris (COP21) held in December 2015, leaders from 195 countries committed to a global, net decarbonization goal in order to address climate change. The goal is to “pursue efforts to limit the (global average) temperature increase to 1.5 °C above pre-industrial levels”.
However, the way in which this goal will be accomplished is not included in Paris documents. The authors of Pathways for balancing CO2 emissions and sinks, an article published in Nature last Friday, use assessment models to determine scenarios in which the goals of the COP21 can be met. According to their research, it is necessary to both reduce greenhouse gas emissions and preserve carbon sinks, with net emissions peaking in the next ten years.
The research model shows fossil fuel consumption must be reduced to less than 25 percent of the global energy supply by 2100, compared to the current rate of 95 percent. The rate of deforestation needs to be reduced drastically in order to achieve 42 percent decrease in cumulative emissions by 2100.
Renewable energy such as wind, solar, and bioenergy needs to increase by about 5% each year until 2022. However, renewable energy must be paired with negative emissions technologies such as reforestation and revitalizing ocean ecosystems. Otherwise, the global temperature will surpass the Paris agreement target to reach 2.5°C.
“The study shows that the combined energy and land-use system should deliver zero net anthropogenic emissions well before 2040 in order to assure the attainability of a 1.5°C target by 2100,” said Michael Obersteiner, coauthor and IIASA director.
These numbers may seem overwhelming but science is showing that some countries are moving in the right direction. China has increased their renewable energy consumption and entire countries such as Denmark have committed to 100% renewables.
Read the published paper, Pathways for balancing CO2 emissions and sinks, from Nature: https://www.nature.com/articles/ncomms14856