Sean Bromilow
Early this February, space enthusiasts around the world tuned in at 6:30am GMT to watch as a SpaceX Falcon 9 rocket fired NASA’s newest satellite into orbit, where it directed its gaze back down to Earth from a viewpoint higher than the International Space Station.
This was the grand lift-off of the PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) mission, the first NASA satellite to launch from Cape Canaveral into polar orbit since 1960. After over a decade of research, hard work and planning (not to mention the $950 million budget) PACE represents a huge step forward for climate research, gathering important new data about our planet’s health from the oceans and clouds. This monitoring will be done, in part, by focussing on an unexpected new subject for NASA’s attention – the humble plankton.
As global temperatures rise, this essential process is in danger of disruption
As its name might suggest, the study of plankton will be a key aspect of PACE’s mission statement, and with phytoplankton (that is, plant-like plankton) producing nearly 50% of the world’s oxygen whilst making up only 1% of its total biomass, it’s more important than ever to try and understand how these little powerhouses can change our rapidly deteriorating environment. As NASA scientist James Werdell puts it, “If you’re a citizen of the world who likes breathing, and you like eating, and you like going to the beach, say thank you to a phytoplankton next time you see one”.
We’ve certainly got plenty to be grateful to them for, since not only do our microscopic friends produce oxygen through their photosynthesis, they also extract carbon dioxide from the atmosphere to fuel the process. Waste material from dead phytoplankton then leads to a portion of this absorbed carbon being sent down into the ocean depths, sequestering away around 10 billion tons of carbon globally per year, in a process called the biological pump. However, as global temperatures rise, this essential process is in danger of disruption.
The data PACE gathers might become an essential part of climate modelling
Larger phytoplankton, the kind mainly involved in the biological pump, dominate populations in colder, less acidic waters – meaning the oceans are slowly becoming less favourable to them as global warming increases ocean temperatures and acidity. In their place, smaller phytoplankton tend to bloom and flourish, leaving fewer nutrients behind for their bigger – and more preferable – cousins. A worrying prediction in models of our future seas is that smaller plankton might begin to dominate closer and closer to the poles, helping to stall the engine of the biological pump and potentially accelerating the effects of global warming. As such, studies of different plankton species, how they spread, mix and bloom across the world’s oceans, are key to a deeper understanding of these effects.
PACE has been equipped with a new type of instrument for this job called the OCI (Ocean Colour Imager), an optical imager freshly developed by NASA to have a massively increased coverage of colours across the visible light spectrum. Rather than dividing incoming light into only a handful of channels, which would roughly distinguish between green plants and blue seas, the OCI will split light into over 200 different channels, allowing PACE to spot individual plankton species based solely on their specific shade of green. With the new ability to track ocean life at such high resolution, the data PACE gathers might become an essential part of climate modelling, giving us more accurate predictions and a better understanding of our planet’s future.
In the end, it may turn out that best way to study our impact on the global ecosystem is by looking at its tiniest residents.
Sean Bromilow
Featured image courtesy of NASA via Unsplash. Image license found here. No changes were made to this image.
For more content including Uni News, Reviews, Entertainment, Lifestyle, Features and so much more, follow us on Twitter and Instagram, and like our Facebook page for more articles and information on how to get involved.
If you just can’t get enough of Lifestyle, like our Facebook as a reader or contributor.
