Context: MethaneSAT — a satellite which will track and measure methane emissions at a global scale — was launched aboard a SpaceX Falcon9 rocket from California, United States.
About Methane:
- Methane (CH4) is a colourless, odourless, flammable gas that is the main component of natural gas.
- It is a powerful greenhouse gas i.e., it traps heat in the atmosphere and contributes to global warming. It is the second largest contributor to climate change, after carbon dioxide (CO2), responsible for 30% of global heating since the Industrial Revolution.
- Methane remains in the atmosphere for only about 12 years, but has a much more powerful warming impact than CO2.
- According to the United Nations Environment Programme, over a period of 20 years, Methane is 80 times more potent at warming than CO2.
- Over a 100 year timescale, Methane is about 21 times more potent than CO2 at trapping heat in the atmosphere. This means that one tonne of methane emitted into the atmosphere has the same warming effect as 21 tonnes of CO2.
- Methane also contributes to the formation of ground-level ozone — a colourless highly irritating gas and a harmful environmental pollutant that forms just above the Earth’s surface.
- According to a 2022 report, exposure to ground-level ozone could be contributing to one million premature deaths every year.
- Ground-level ozone can cause various other health issues, including- Respiratory problems like asthma and bronchitis, Reduced lung function and Cardiovascular issues.
Note: Global Warming Potential (GWP) describes how much impact a gas will have on atmospheric warming over a period of time compared to carbon dioxide. Each greenhouse gas has a different atmospheric warming impact, and some gases remain in the atmosphere for longer than others. Carbon dioxide (CO2) has the lowest warming potential, is the most abundant and lasts for thousands of years, so it is used as the baseline.
Methane Emission Sources
- There has been a steady increase of methane in the atmosphere, with concentrations currently over two-and-a-half times greater than pre-industrial levels.
- Around 50-65% of total methane emissions globally are attributed to human activities, also known as anthropogenic emissions.
- The remaining 35-50% comes from natural sources, with wetlands being the largest contributor within this category.
Anthropogenic Sources
- Agriculture: Agriculture is the biggest emitter, responsible for roughly a quarter of emissions. Most of that is from livestock (cows and sheep release methane during digestion and in their manure) and rice cultivation, where flooded fields create ideal conditions for methane-emitting bacteria.
- Energy sector: Coal, oil, and gas is the second largest source of human caused Methane emissions. Methane leaks from energy infrastructure, such as gas pipelines, and from deliberate releases during maintenance.
- Discarded household waste also releases large quantities of Methane when it decomposes, if left to rot in landfills.
About MethaneSAT
- MethaneSAT is a small Earth observation satellite with the goal of monitoring and studying global methane emissions in order to combat climate change.
- Developed by: Environmental Defense Fund in partnership with the New Zealand Space Agency, Harvard University among others.
- MethaneSAT will orbit the Earth 15 times a day, and monitor the oil and gas sector. It will create a large amount of data, which will tell how much methane is coming from where, who’s responsible, and are those emissions going up or down over time. (Fossil fuel operations account for about 40% of all human-caused methane emissions)
- MethaneSat will be used in the future to track methane from coal mines, landfills and farming (the other main sources of human-caused emissions).
- The challenge: Tracking the source of methane emissions and measuring them has been quite challenging.
- While some satellites can provide high-resolution data, they can only scan specific, pre-targeted sites. Others can examine larger areas and detect large emitting events, but cannot scan smaller sources that account for the majority of emissions in many, if not most, regions.
- Due to this discrepancy, according to an International Energy Agency (IEA) report, global methane emissions are about 70% higher than levels reported by national governments.
- MethaneSAT is expected to fix the issue. It is equipped with a high-resolution infrared sensor and a spectrometer, the satellite will fill critical data gaps. It can track differences in methane concentrations as small as three parts per billion in the atmosphere, which enables it to pick up smaller emissions sources than the previous satellites.
- MethaneSAT also has a wide-camera view — of about 200 km by 200 km — allowing it to identify larger emitters so-called “super emitters”. The collected data will be analysed using cloud-computing and AI technology developed by Google and the data will be made public through Google’s Earth Engine platform.
Significance
- MethaneSAT will be a tool to track the implementation of more stringent methane management policies and help meet these targets.
- For instance, more than 150 countries signed the Global Methane Pledge in 2021, to cut their collective methane emissions by at least 30% from 2020 levels by 2030.
- At COP-28, more than 50 companies committed to virtually eliminating methane emissions and routine flaring.
- The data collected by the satellite would be publicly available which can be accessed by anyone in the world. It would usher in a new era of transparency in meeting methane commitments made by governments and corporations.