In May 2016, atmospheric monitoring in north-west Tasmania recorded carbon dioxide above 400 parts per million (ppm) for the first time. These results were confirmed in measurements produced by the Earth System Research Laboratory in Hawaii in September 2016. 400 ppm is the level of concentrations of CO2 which will lead to a 2ºC rise in global temperatures from pre-industrial levels. The United Nations Framework Convention on Climate Change declares this to be ‘the highest rise we can afford if we want a 50% chance of avoiding the worst effects of climate change’. Current projections are for concentrations to continue to rise to as much as 500–1000 ppm by the year 2100.
Efforts to combat climate change are being targeted towards natural methods through areas such as afforestation, restoration of degraded coastal or marine habitats and soil carbon sequestration. Also seen to be viable options to reduce levels of atmospheric CO2 are technological and engineering advancements such as Direct Air Capture (of CO2) and Enhanced Weathering.
Bio-energy Carbon Capture and Storage (BECCS) technology is seen by many scientists as a viable and important tool in ameliorating rising CO2. Put simply, and illustrated below, BECCS denotes the process of capturing waste carbon dioxide from large sources such as fossil fuel power plants, transporting it to a storage site, and depositing it where it will not enter the atmosphere, normally in an underground geological formation.
Bio-energy, or biomass (also shown below), is the waste organic material derived largely from food production and agricultural processes, including wood and wood waste, straw, manure, sugarcane, and other products.
The net effect of BECCS technology and bio-energy as a renewable source, as opposed to burning fossil fuels, combined with the CO2 capture and sequestration, effectively removes CO2 from the atmosphere, leading to negative CO2 emissions.
Scientific investigation and debate regarding the effectiveness of BECCS technology, conducted from 2010, concluded that a potential existed to a make a significant contribution to reducing atmospheric CO2. At present, according to the Global CSS Institute, BECCS projects are operating in the USA in Illinois, Kansas and North Dakota. Others are in Tanzania and Brazil, and in Europe a number of projects are underway with more in the research and planning stages. Noteworthy, however, in terms of the technology being tested and available to be implemented, scientists reporting in Nature Climate Change believe BECCS will need another 4 to 5 years of research and testing before it can be brought into mainstream climate policy.
The problem is BECCS operations are not suited to all regions due to factors that include high cost, social issues, geology and the availability of sufficient amounts of suitable biomass. These factors translate into significant global-scale challenges. For BECCS to make a real difference, for instance, 50 to 100 BECCS projects need to be initiated and to have reached operational capability within the next two years, and several hundreds more shortly thereafter.