TROPOMI: Our Carbon-Monitoring Eye in the Sky

To combat global warming, we need to reduce our greenhouse gas emissions. Carbon dioxide and methane make up 90% of Europe’s greenhouse gases. But how do we know precisely how much we’re producing, and what’s causing these emissions to rise in the first place? Manu Goudar, an atmospheric scientist at the Netherlands Institute for Space Research (SRON) is working on the answer. While SRON is usually known for its focus on astronomy, the institute is also active in earth science and climate research.

Manu harvests data from the Tropospheric Monitoring Instrument, better known as TROPOMI, on board the European Space Agency’s (ESA) Copernicus Sentinel-5 Precursor (S5P) satellite. SRON and the ESA were joint developers of TROPOMI. In 2017, it was launched into space to monitor the Earth’s lower atmosphere, the troposphere, where pollution from human activities is most visible. Every day TROPOMI maps the entire Earth’s atmosphere and generates huge amounts of data fundamental to our understanding of climate change and air quality. “I identify anomalies in carbon monoxide (CO) data from the satellite,” Manu explains. “Then I try to understand the reason behind the anomaly and compute CO emissions using computer models.”

TROPOMI measures direct sunlight and reflected sunlight from the Earth’s surface and atmosphere. Its Short Wavelength Infrared detector monitors carbon monoxide, methane and water vapour, all greenhouse gases polluting the atmosphere. Although TROPOMI doesn’t measure carbon dioxide directly, its carbon monoxide measurements help researchers estimate how much carbon dioxide is being generated on Earth by, for example, forest fires or burning fossil fuels.

Manu enjoys working on these large-scale database modelling systems because they’re quite challenging and require integrating multiple subjects. Just think how hard it is to predict the weather, another large-scale system. At the moment, he’s working on integrating four different databases, which include data from two satellites (TROPOMI & Suomi NPP), meteorological data from the European Centre for Medium-Range Weather Forecasts, and the global fire assimilation system. He says, “Some people look at global emissions, but I wanted to look at localised fire emissions. The exciting thing about this is that we can quantify the emissions from TROPOMI measurements locally in time and space.  These very localised measurements will help with more accurate modelling of fires and also air quality in the future.” The plan is to eventually provide public access to these databases so other researchers can use them too.

Next up, Manu will be working on data from the pioneering satellite mission called Twin ANthropogenic Greenhouse Gas Observers, or TANGO, set to be launched in 2026. This project involves two satellites which will be able to zoom in on specific areas and provide even more accurate measurements of the greenhouse gases, carbon dioxide, methane, and nitrogen dioxide. As with TROPOMI, SRON is one of the key partners in the mission showcasing its expertise in space science, key technology research, and instrument building.

Coming from a fluid dynamics background, Manu appreciates having the chance to expand his skill set at SRON. He says, “I work on image processing, which is completely different from my previous field of work. I do a lot of data analysis and use optimization in conjunction with fluid dynamics. I have also written nearly 8,000 to 10,000 lines of code in the last two years. It's exciting to learn different things, and people here give a lot of support and help.” Manu is originally from India and moved to the Netherlands in 2010 for his Master’s and PhD. After working in both industry and university settings, he moved to SRON two years ago and really enjoys the work environment there. He finds the atmosphere stimulating and everyone is motivated to produce their best work. There’s a very open and constructive working culture which encourages people to talk honestly, also about mistakes and how to correct them. He says, “With the TROPOMI satellite, we’ve detected some things that people never thought of, like large amounts of methane emissions from landfills. Work like this makes you feel like you are doing something very important for society, and SRON enables you to contribute to society at a much higher level. And it makes you feel confident and happy about your work.”