Monitoring the Earth from Space
What can we learn from just looking back at ourselves?
When it comes to space exploration, we tend to focus on the missions that are travelling beyond Earth and throughout our Solar System. However, a very important area of space that is sometimes overlooked is the study of our own planet, Earth.
This is what scientists call Earth Observation – an area of space that is expected to be worth $66.1 billion in 2020. Scientists use satellites orbiting the planet to monitor it in many ways.
Some of these are probably familiar in your everyday life and some may surprise you, so let’s have a look!
Predicting the weather
The weather on Earth is very dynamic and continuously changes from one place to another. This is constantly being monitored by satellites such as the Meteosat satellites.
By studying things such as the movement of clouds and the changes in surface temperatures all around the world, scientists can make more accurate weather predictions than ever, helping us to know if we need to pack an umbrella or wrap up warm.
Satellites monitoring the weather also help keep us safe.
Sometimes extreme weather systems can cause sudden disasters such as tropical storms and flooding. Satellites can monitor and predict the movement of these disasters and help inform people to take precautions or even evacuate.
In recent years Britain has experienced some extreme flooding.
In 2015, Storm Desmond hit on the weekend of 5-6 December and brought with it severe flooding, causing 43,000 homes to be without power. A system of satellites, as part of the Copernicus programme, monitored and warned authorities about the areas at most risk and helped issue appropriate warnings and advice.
Without satellites, the prediction of these disasters would be much more difficult and human life would be at a higher risk.
Monitoring the environment and the creatures in it
With many species now under threat from human activity, satellites may provide a way in which wildlife can be monitored and protected.
Using satellites, scientists can determine the movement of animals, the numbers of a certain species, and even help prevent poaching using Earth Observation techniques.
Habitats are being lost all over the world – especially during wildfires such as the 2019 wildfire that has destroyed large parts of the South American rainforest. Satellites can not only help us track and combat the spread of fires in real-time, but also understand the impact these fires have on local wildlife.
For many years, scientists have been keeping track of wildlife numbers, using tag methods and visual imagery from low in the sky. But this method is not the most efficient way, especially when dealing with large animals in remote locations.
Now scientists are using GPS collar locators and a very high-resolution satellite. The advantage of a satellite is that it can monitor a lot of the Earth all at once. With satellites in space, it is possible to witness everything from the mass migration of wildebeest to the movement of penguins in Antarctica. On the recent BBC programme, ‘Earth from Space’, satellites were even used in monitoring the movement of elephants.
Satellite can take data over a long time period and make comparisons to detect any changes. This will provide scientists with data and information about the animals and their habitat which they can then use to determine the areas that need additional protection and environmental management.
Tracking diseases from space
In the future, it may even be possible for satellites to track diseases.
NASA and the Peruvian government are working on a satellite system that hopes to be able to predict an outbreak of malaria months in advance and maybe even prevent them altogether.
What they hope to achieve is a system that can locate the prime breeding grounds for mosquitoes. These areas feature warm temperatures and calm water, such as ponds, puddles or even lakes. These can be found and traced through a fleet of Earth observing satellites.
Currently people with malaria tend to get diagnosed at hospitals, which can be very far away from where these people work or live. This makes it very hard for the government to locate the original source of the malaria-carrying mosquitoes. This new method will hopefully help the government locate the appropriate areas and take action to limit, predict and prevent malaria outbreaks.
Finding out what is in the air
Air pollution is an increasing problem in large cities.
The World Health Organisation has stated that air pollution is the cause of more than 4.2 million deaths every year. Much of the harmful air pollution is created from human activity such as the burning of fossil fuels and transportation. However, some air pollution comes from natural events such as volcanic eruptions and forest fires. It is therefore important for our own welfare to find ways of monitoring and improving the air quality around us. This is another way in which Earth Observation satellites can help.
In 2017, the European Union launched an air quality mission called Sentinel-5p, as part of its Copernicus Earth Observation programme. Sentinel-5p carries an instrument that monitors the atmosphere for concentrations of harmful air pollutants such as nitrogen dioxide, carbon monoxide and sulphur dioxide. All of these gases are produced during combustion in either factories or vehicles such as cars and trucks.
It’s possible to explore some of the Sentinel data through the online portal EO Browser. This tool can show the concentrations of some of these air pollutants from almost anywhere in the world.
With data from satellites such as this one, scientists can help advise governments on which areas are the most affected from air pollution and create solutions to improve the quality.
These are just a few of the many uses of Earth Observation satellites. With increasing concern about the effects of climate change, Earth Observation is one of the key elements in tackling this on a global scale. Satellites also provide valuable weather forecasts and help us predict and monitor natural disasters.
The UK’s hub for Earth Observation research is actually here in Leicester at the National Centre for Earth Observation (NCEO). The NCEO makes up the UK’s international contribution to environmental science. Institutes like this are exploring new ways to use satellites, with a huge focus on air pollution and reducing the effects of climate change.
Without the global view provided by our Earth Observation satellites, we simply wouldn’t have the same ability to understand and protect planet Earth for future generations.
About the author: Sam Shingles is a physics student at the University of Leicester and works as a Science Interpreter at the National Space Centre.