Satellites for Climate Change? Seriously?

If you looked up at the sky with your naked eyes, it would be hard to accurately guess how many satellites there are. In fact, over 5,000 satellites currently hover above the planet, gathering crucial data to power our global GPS system, forecast the weather, and, surprisingly…combat climate change. 

Since the mid-1970s, Geological Survey Landsat Earth Observation Satellites have provided undeniable evidence of the challenge unfolding in front of our eyes, offering high-quality imaging, mapping, and monitoring services that help track global warming. Although certain technologies have shown promise in slowing down global warming—the global temperature increase by the end of the year 2100 is predicted to slow down to three degrees Celsius—a more forceful solution is urgently required to ration global warming below the 1.5 degree Celsius threshold. The space industry may provide much-needed solutions. Yet, as satellite companies attempt to fill in this market niche and advertise the exciting potential of their new technology, further analysis shows that satellite technology might not be as beneficial as stated; further research is required to mature the technology and render it suitable for fighting climate change.  

Satellite technology tracks human-caused methane emissions, which contribute significantly to global warming by making the atmosphere more insulated and trapping heat from the Sun on Earth. Satellites provide real-time updates on atmospheric changes and pinpoint the origin of greenhouse gas emissions from a range of sources, such as oil wells, landfills, industrial operations, and farms. Many scientists believe that governments can use this data to formulate regulations and root out companies responsible for methane emission. Ironically, the satellite launches also pollute the atmosphere and disturb the delicate balance of “good” and “bad” gases. A thousand hydrocarbon-based rocket launches per year—the amount proposed for space tourism—would cause ozone loss up to 6 percent in polar regions. Additionally, the carbon dioxide and water in a rocket’s exhaust trail trap heat and absorb sunlight, further contributing to global warming. Those two downsides of rocket launches are enough to offset the benefits brought by the satellites. 

Satellite technology also helps tackle global warming by generating renewable energy sources. Burning of fossil-fuels supplies 84 percent of global energy demands. Solar energy is dramatically underused despite the limitless amounts available for human consumption, unlike fossil fuels. To utilize solar energy, large mirrors attached to satellites can reflect unused light back to earth, capturing much more energy than terrestrial solar panels. However, this technology is far from ready. It is unclear whether satellites, which generate solar power, have a high-enough efficiency rate to justify the gaseous emissions they produce: Current satellite models have a trifling 5 percent efficacy, while at least 20 percent efficiency is required for a space-based solar plant to work. This predicament prevents widespread adoption of the technology, at least for now. 

There are many controversies regarding satellite technology, but we can harness its environmental benefits by perfecting current legal regulations. Current steps taken by the United States Environmental Protection Agency regulate launch sites, but the laws are general and ill-defined. For instance, they warn launch sites to “not cause significant cumulative effects to the environment” without quantifying what a “significant” effect is. This could prevent companies from fully researching the emissions of present-day rocket launches, ignorantly launching flights that should not be launched. Since satellite applications in climate protection are young technologies, more detailed estimation of launch impacts should be created to limit unnecessary spaceflight activity. 

Despite policy improvement, satellite technology improvements over the past 10 years have made scientists confident in its prospects. The European Space Agency (ESA) is seeking an option to fuel rockets using liquid, green hydrogen produced through water electrolysis. This hydrogen production method benefits the environment, as it does not cause greenhouse gas emissions, unlike conventional methods such as methanol reforming, which reacts methanol with steam and produces a great amount of carbon dioxide gas. This technology could successfully reduce rocket CO2 emissions while maintaining launch efficiency. 

The collective interest in using earth-observing satellites dedicated to fight climate change will only continue to grow as the space industry thrives. Yet, many reservations remain about the  ability of these satellites to truly counteract the global warming crisis due to their limited efficacy and gaseous emissions. For advancements in satellite technology to effectively fight climate change, the potential problems must be promptly addressed. It is imperative to ensure that efforts devoted to developing climate-monitoring satellites are not offset by the pollutants created by launch exhaust.