Why space matters in the fight against climate change

As Himalayan glaciers rapidly shrink due to climate change, the region faces increasing dangers, including catastrophic Glacial Lake Outburst Floods (GLOFs).

The Indian Space Research Organisation (ISRO) has played a crucial role in tracking these changes, using satellite technology to monitor the growth of glacial lakes, which expanded by over 27% since 1984.

This vital data helps forecast potential flooding events, protecting vulnerable downstream communities. The swift melting of glaciers affects over 400 million people who rely on glacial water for drinking, agriculture, and their livelihoods.

In this race against time, space is a powerful ally in safeguarding lives and environments.

A recent study by the Indian Institute of Science (IISc) reveals that Bengaluru has seen a 93% reduction in lake and forest areas since the 1970s. Over the past 50 years, the city has lost 79% of its water bodies and 88% of its forests, as construction activity has increased by more than 1,000%. This rapid urban growth has increased Bengaluru’s vulnerability to climate threats such as flooding and heatwaves. Civic groups have been monitoring these shifts, using space technology to observe glacial retreat and lake expansion.

When NASA launched the first weather satellite, TIROS 1, in 1960, it marked a turning point in humans’ ability to understand the Earth’s climate. For the first time, the planet could be observed as a whole, beyond local weather stations and ground measurements.

This new perspective allowed scientists to gain an unprecedented view of atmospheric patterns, ocean currents, and land use, making it easier to detect changes that had previously gone unnoticed.

By the 1970s, satellites had already started picking up alarming signs of human impact on the environment. This progress gave scientists the tools they needed to keep track of climate change, making space a valuable resource for collecting data and monitoring the planet’s health.

How satellites help monitor climate change

Satellite technology, once mainly used for communication and navigation, is now essential for monitoring global climate change. Today, satellites help track a wide range of important environmental factors, such as weather patterns (via the INSAT series), air and surface temperatures (with satellites like Copernicus Sentinel-3 and Oceansat-2), and carbon dioxide and methane levels (monitored by Sentinel-5P). They also provide data on land use and cover (from the IRS series), glacier health (ICESat-2), and vegetation condition.

With over 150 climate satellites currently in full operation or semi-active status, the real-time data they collect is crucial for developing solutions, policy decisions, and climate models. 

According to the World Economic Forum, the Earth Observation (EO) market is expected to reach $700 billion by 2030. EO satellites, equipped with cutting-edge sensors, have a unique ability to collect essential data from orbit, providing researchers with a global view of ecological changes. For example, HySIS (Hyper Spectral Imaging Satellite), launched by ISRO in 2018, gathers valuable data in various sectors such as agriculture, forestry, geology, coastal regions, and pollution surveillance.

Orbiting at 636 km above Earth, HySIS collects data in 55 distinct wavelengths, enabling it to evaluate land use and monitor the impact of industrial activity. Its ability to capture images in visible, near-infrared, and shortwave-infrared wavelengths helps create more climate-resilient infrastructure and promote sustainable practices in urban and agricultural areas.

Satellites use a variety of sensors to gather data on different environmental factors, each designed for a particular purpose. Optical sensors, for example, capture sunlight reflected off the Earth’s surface, generating high-resolution images that help monitor vegetation, water bodies, and land use. Lidar sensors use laser pulses to gauge distances, generating intricate 3D maps that are particularly valuable for monitoring changes in topography and the thinning of ice sheets in polar areas. SAR (synthetic aperture radar) is used to observe weather trends, deforestation, and fluctuations in polar ice. At the same time, thermal infrared sensors identify heat emissions, assisting in the assessment of surface temperatures.

These sensors are currently very advanced, yet continuous research is enhancing their precision, enabling broader data collection and better monitoring. After the data is collected, it is processed to eliminate noise and adjust for influences such as atmospheric interference.

This leads to precise, spotless datasets that can be used for assessing environmental threats, including deforestation, glacier melting, or drought. These findings are subsequently communicated to decision-makers, including government officials and emergency teams, who
utilise them to act, mitigate climate-related hazards, and adjust to the evolving environment.

Scale of climate monitoring

A major challenge in climate monitoring is the lack of coverage in isolated areas like the Arctic and Antarctic oceans. The NISAR mission, a collaboration with NASA and ISRO, intends to fill this gap using cutting-edge technology.

The swift advancement of satellite technology is creating new opportunities for monitoring pollution. For instance, enterprises are deploying satellites that focus on monitoring methane emissions. These satellites can pinpoint the precise origins of methane leaks in the oil and gas sector and other sectors, allowing companies to quickly act to decrease emissions and adhere to environmental standards.

The scale of global climate monitoring has expanded significantly, with more investments and collaborations in satellite technology. Climate-focused satellites are not just an investment in technology but a step toward creating action for climate adaptation and mitigation strategies. The incorporation of artificial intelligence (AI) and machine learning into the analysis of satellite data is set to transform climate science, and SpaceTech startups can play a unique role in accelerating this change. 

The private sector’s involvement in climate change solutions is growing. Indian companies are making a mark in space-based climate monitoring. Internationally, startups are deploying pioneering satellite-based technologies that complement public initiatives, enabling global collaboration in monitoring and responding to climate threats. This synergy between emerging startups and seasoned space agencies is accelerating the development of actionable, scalable climate solutions essential for creating a sustainable future.

(The writer is co-founder, CEO, and CTO of an aerospace company)