The year 2024 was a record year, and not in a good way. In July the average temperature on Earth was highest it's been at least 175 years, with July 22 specifically being the date hottest day recorded. It was last summer hottest summer since about the year 1880, this year's hurricane season kicked off with Beryl - the earliest Category 4 hurricane on record - and a report published in June confirmed that human-induced global warming has reached an all-time high.
But it's not just the record-breaking headlines that scientists are concerned about. Since this year they have become glaciers melting As a result of all this man-made heat, sea levels are rising at an unprecedented rate irreversible are rising due to the melting of glaciers, coastal communities are being ravaged by storms exacerbated by such sea level rise combined with high temperatures, and animals are being turned off from their homes because Earth changes too much and too quickly. Just last month we saw Hurricane Helene destroying cities and claiming lives - and its power is indeed connected to climate change.
It's certainly tough to see the facts laid out like this, especially considering how much those paragraphs leave unsaid. However, this sentiment brings up something very important: it is, at a basic level, valuable that this information exists at all. Perhaps the biggest mitigating step in the fight against climate change is turning facts into actionable tasks and convincing policymakers to make major changes in the way our world is governed. The climate crisis is a deceptively political problem, which means the Earth's future depends on data - and, depending on how you look at it, that data depends on an unlikely source: space exploration.
"The only way we can make connections between the various phenomena that drive the complex functioning of our planet, and distinguish between the natural and man-made, is to connect the dots between them," says Cedric David, a scientist at NASA. Jet propulsion laboratory (JPL) in Southern California, Space.com told us.
'For this we need a continuous fleet of space rangers high in space room ' he said. 'Just as we do annual check-ups at the GP, we need to diagnose the health of our own planet.'
Related: World Space Week 2024: How space technology is arming scientists in the fight against climate changeWhat exactly do climate satellites do?
The word "satellite" is used a lot these days, but in basic terms it simply refers to any object sent into our planet's orbit to perform a particular task. We have communication satellites to make our cell phones work, navigation satellites to make sure Google Maps gives us the right directions, and experimental satellites for pure science, like this that is currently being tested solar sail technology.
In addition to the satellite party, we also have climate satellites.
"NASA and other international space agencies inspire the world with our exploration of our planets solar system and beyond," David said. "But a significant impact that space research has had is also a much better understanding of our own planet."
For example, there are satellites with spectrometers that can reveal the concentration of carbon dioxide in our atmosphere, which is important because experts have revealed that the level of carbon dioxide in the atmosphere is increasing, mainly due to the combustion of fossil fuels such as coal and oil. More carbon dioxide in the atmosphere means a "supercharged" greenhouse gas effect, as the US National Oceanic and Atmospheric Administration (NOAA) puts it - and a supercharged greenhouse gas effect means a increase in global temperature. To be clear: there is such a thing as 'natural' climate change. But right now, nature is not the main cause of global warming. Human activities are, as research shows time and again.
There are further many satellitessuch as NASA's Landsat spacecraft, which can obtain images of how forests are shrinking in size as industries cut them down to make room for commercial ventures. Footage can also help track issues such as changing animal habitats, forced migration of wildlife and... declining food supply for certain species. There are also spacecraft with lasers that can help measure speed ice caps melt. Still others have synthetic aperture radars that show how our planet responds earthquakeswhat could be increase in frequency as the earth warms.
"I worked at NASA Over the last ten years I have seen quite a few remote observations that have really given me food for thought," said David. 'I think gravimetry is the most incredible thing.'
Satellite gravimetry helps scientists measure Earth's gravitational influence - and especially subtle changes in our planet's gravitational field. Because gravity is directly correlated with mass objects, this means the technique can accurately measure when ice mass is lost, how the oceans are rising, and even fluctuations in groundwater supplies. "Satellites can see what we can't see with our own eyes: changes in deep underground water storage that require us to dig deep into the ground to witness firsthand," David said.
"That's just mind-boggling."
The future of the earth is our future
The list goes on - and that's a good thing. Having so much data allows scientists to do their due diligence and gather large amounts of evidence that people in power can sift through before making decisions that impact the climate. At major climate meetings - the COP conferences are probably the best known - that evidence can be presented to officials as part of a plea for change. Without information, communication is not easy.
But satellite data is often also practical in the short term.
For example, hurricane watchers help meteorologists predict where storms will fall - a crucial task, as these storms will undoubtedly increase in intensity and frequency as the climate warms - and methane emissions trackers can identify where exactly the greenhouse gas hotspots are located.
David also points out that in a 2018 report, the US National Academies recommended that NASA build a series of spacecraft that will form the Earth System Observatory (ESO). This observatory, he explains, would be tasked with observing the movements of our planet's atmosphere, the creation of rain, the fortunes of continents and the ongoing movements of mass around the world.
However, much more can be done.
"One major challenge remains: accurately measuring our snowpacks from space. Snow is notoriously difficult to quantify; we can see the area it covers, but it's still difficult to sense how deep it is and how close it is," he said. . "Given that many regions - including California, where I live - where snowmelt is a primary source of freshwater, advancing our understanding of snow in difficult-to-access areas is imperative."
David believes all this information is "absolutely essential". But I asked him to choose the most useful type of satellite data he needed when thinking about possible solutions to climate change; he opted for radar altimetry.
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"Since 1992, a series of radar altimetry satellites have been circling our Earth in constant operation and have allowed us to see the unmistakable: the oceans are constantly rising," he said. "The 30-year sea level rise curve is indisputable evidence that our climate is changing."
In other words, we have a continuous stream of data telling us the same thing over and over again: Earth's climate is changing, and that's because of the people who populate it. It's data like this that should dictate our response.
"As we continue to explore our universe and inspire people, we are constantly reminded that so far the only place we have found life is here on Earth," David said. "We can keep looking for a Plan B, but so far there is only Plan A: our own planet."
