Context:

  • The Trump-era U.S. administration reportedly asked NASA to prepare for the shutdown of two key satellites — OCO-2 and OCO-3 — that monitor atmospheric carbon dioxide (CO2) and crop health from space.
  • While NASA stated the missions were "beyond their prime" and needed to align with budget priorities, many scientists and experts argue these satellites remain scientifically valuable and cost-effective.

WHAT ARE OCO SATELLITES?

  • OCO = Orbiting Carbon Observatory
  • These are Earth-observing satellites specifically designed to measure CO2 levels in the atmosphere and support climate change research.

TIMELINE & DEVELOPMENT

  • OCO-1 (2009):
    • Launch failed due to a fairing separation issue, preventing it from reaching orbit.
  • OCO-2 (2014):
    • Successfully launched.
    • Measures CO2 concentrations, identifies sources and sinks, and detects plant photosynthesis through solar-induced fluorescence.
  • OCO-3 (2019):
    • Installed on the International Space Station (ISS).
    • Built using spare components from OCO-2.
    • Offers time-variable observations due to the ISS’s orbit.

HOW DO THEY WORK?

  • OCO-2 follows a sun-synchronous polar orbit, observing each location at the same local time daily. This ensures consistent data for long-term trends.
  • OCO-3 is mounted on the ISS, which orbits Earth every 90 minutes. It observes the same area at different times of day, providing dynamic CO2 data.

WHY ARE OCO MISSIONS IMPORTANT?

1. Global CO2 Monitoring
  • Before the OCO missions, scientists mostly relied on ground-based stations, which gave limited regional data.
  • OCO satellites enabled global, high-resolution monitoring of CO2 emissions, their sources, and absorption zones (sinks).
2. Climate Change Research
  • CO2 is the primary greenhouse gas responsible for global warming.
  • The data helps:
    • Track emission levels.
    • Evaluate carbon sinks like forests and oceans.
    • Improve climate models and guide climate policy.

SCIENTIFIC DISCOVERIES

  • It was traditionally believed that tropical rainforests absorbed the most CO2.
  • OCO-2 data revealed the crucial role of boreal forests (northern coniferous forests) in CO2
  • Showed that forests can become carbon sources during droughts, deforestation, or ecosystem stress.

AGRICULTURAL APPLICATIONS

  • OCO satellites detect the “glow” emitted by plants during photosynthesis (solar-induced fluorescence).
  • Benefits include:
    • Monitoring crop health and growth cycles.
    • Assessing drought conditions.
    • Forecasting yields.
  • Used by agencies like NASA, US Department of Agriculture, and private agricultural firms.

WHAT IS THE COST?

Development Cost
  • Approximately $750 million was spent to design, build, and launch OCO-2 and OCO-3.
Annual Operating Cost
  • Around $15 million per year, including:
    • Data download
    • Calibration
    • Maintenance
Expert Views
  • Scientists argue that the operational costs are minimal compared to the value of the data.
  • Ending these missions would be economically and scientifically shortsighted.

WHAT HAPPENS NEXT?

  • Both satellites are currently funded until September 30, 2025.
  • The S. Congress may decide to extend or terminate the funding.
Conclusion The OCO missions represent a major leap in climate science and agricultural monitoring. With climate change accelerating, these satellites provide critical data for understanding and managing Earth's carbon budget. Shutting them down could undermine global scientific progress and limit the evidence-based approach needed for environmental policymaking.