Samantha Zeitz

Scientific experts are saying to comply with the Paris Agreement countries are going to have to start putting a lot more effort into achieving climate change goals.

A new study from the International Institute for Applied Systems Analysis (IIASA) shows that combined energy and land-use systems will have to become emissions free before 2040 to limit the average increase of global warming by 1.5 degrees Celsius by 2100. The IIASA is a scientific institute that does research on environmental, economic, and social change of global importance. The institute study included a global model of the carbon system, considering carbon release and contributions from natural and human activities. It accounts for fossil fuel emissions, agriculture, land use, food production, bioenergy, and carbon uptake by natural ecosystems.

Greenhouse gas emissions can be reduced not only by cutting our emissions, but also by getting removed from the atmosphere through plants, the ocean and soil. The study suggests that by reducing deforestation we could achieve a 42 percent decrease in cumulative emissions by the end of the century.

Another large contributor to the problem is the consumption of fossil fuels. The study says to achieve climate change goals fossil fuels will have to only be responsible for 25 percent of the global energy supply by 2100. Fossil fuels currently supply 95 percent of global energy.  The study shows four different scenarios with a variety of mixtures of renewable energy and fossil fuel energy. The “high-renewable” scenario accounts for wind, solar, and bioenergy increasing by 5 percent annually, allowing net emissions to peak by 2020. However, without negative emission technologies, this scenario would still lead the global average temperature rise of 2.5 degrees Celsius, higher than the Paris Agreement target.

In an IIASA brief, World Bank consultant, Brian Walsh, who led the study, said the high-renewable scenario will be challenging, but is not out of our reach.