Marieke Beckmann, Research Lead, National Physical Laboratory Centre for Carbon Measurement, writes. History was made last week in Paris with 195 nations agreeing a deal to tackle climate change and keep the rise in global temperature caused by greenhouse gases to “well below” 2C.
This will be achieved through pledges from individual countries, knows as Intended Nationally Determined Contributions (INDCs). Given the stalled negotiations seen at Copenhagen in 2009, it is no surprise this agreement is being hailed as a success.
However, INDCs are not binding under international law, meaning individual countries will be responsible for meeting their own pledges, and each will be collecting data in a different way. With so much at stake, the next step must be to standardise the process by which emissions pledges are monitored. This is the only way to see the INDCs monitored and fulfilled across the board, and potentially increased if countries are willing to accept greater ambition in future years.
The ability to prove emission reductions is reliant on accurate measurement, reporting and verification (MRV). Standard models of emissions measurement currently use a bottom-up approach, which estimates emissions based on activity data (for example, electricity consumption in kWhs) multiplied by an “emission conversion factor” (for example, the amount of carbon dioxide attributed to the use of one kWh of electricity).
These factors are established using direct measurements, but some countries do not have the means to make these and rely on data from elsewhere, which may be unsuitable for their particular national circumstances. Emissions from some sectors are very variable and not all measured emissions factors apply to all scenarios. Uncertainties in emissions from livestock or fertilizer use in the agricultural sector for example can be greater than 50%. If we are to ensure the various INDCs are met, we need to improve on these uncertainties, and provide support for developing countries to make their own measurements.
The relevant emissions measurement methods exist and all come with a range of sophistication, accuracy levels and costs. They range from a low-cost portable remote infrared imaging system that can be use to detect the source of leaks, right up to Differential Absorption LIDAR (DIAL), a mobile facility capable of monitoring the concentration, volume and source of atmospheric pollutants remotely at ranges of up to 3km.
Ground-based methods can be partnered with regional networks of sensors that measure atmospheric concentrations of greenhouse gases, and with monitoring from satellites which can give a global view of emissions. For example, the US satellite OCO2 measures carbon dioxide from space, and European organisations have plans for a similar satellite called CarbonSat which would also measure methane emissions.
The Paris deal has given us a real opportunity to make huge inroads into mitigating our impact on the climate. The political will is there, and the technology to implement it is established. A push for the standardisation of robust emissions MRV systems are the last piece of the puzzle in ensuring that INDCs are fulfilled and that the ultimate goal of keeping warming below 2C is achieved.