Fair Oaks, Indiana – to investigate methane emissions near pig farms
Sebastian’s entry grabbed the immediate attention of all the judges because it began “I like pigs. I also love ham. However, when I buy pork, I do not pay for the environmental damage. This damage mainly comes from methane that the pigs produce.” As he went on to point out, methane is a greenhouse gas and therefore climate scientists are extremely interested in monitoring where and how it is produced, and how it travels in the atmosphere. Sebastian calculated that the pigs from farms in the US alone produce an amount of manure (well over 100 million tons) that releases 34 million pounds of methane into the atmosphere each day. And, of course, pigs are not the only animals that are intensively farmed and produce manure (just ask anyone who lives around here about a rather smelly Monday in August)!
He asked for a photograph of a place in Indiana which has a large pig farm – and several nearby dairies. The farms are inland and the area Sebastian requested is quite small, so the astronauts are finding it quite a challenge to zoom in on the requested area from 250 miles up when they are travelling at 5 miles every second. They have been trying – and are continuing to do so whenever they fly over the area at an appropriate time of day in good weather.
Although methane is an invisible gas – light goes straight through it – it does block certain types of infra-red radiation which means that this can be used to detect it. Sebastian therefore asked for a false-colour image produced by combining information about infra-red and visible light reaching the satellite. We have produced images for him using data sent from the MultiSpectral Imager (MSI) on the European Space Agency’s Sentinel 2A satellite in May. Unfortunately, the infra-red wavelengths this instrument responds to do not closely match the narrow bands which are needed to detect the gas, and methane-detecting instruments currently in orbit can only collect results for a relatively large area at a time.
However, scientists and engineers at NASA’s Jet Propulsion Laboratory (JPL) in California are planning a new earth observation mission and, as part of the process of developing the instruments their satellite is to carry, are using a device called the Hyperspectral Thermal Emission Spectrometer (HyTES). This instrument is carried on a plane and can detect methane and pinpoint where it is coming from. Glynn Hulley and Simon Hook from the team have supplied us with an additional image for Sebastian that shows methane escaping from a covered waste lagoon at a dairy farm near Bakersfield, California. In this case, the scientists were actually investigating a nearby gas pipeline but, thanks to what they saw, the farmer was able to stop the leak quite quickly.
Instruments like this can not only detect leaks, but may also help us work out more precisely how much of the methane in the atmosphere is coming from which sources and so improve our climate models and determine the most effective methods for reducing emissions of this powerful greenhouse gas.