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The goal of this project is to extend and improve the measurements of the key climate record of the long-term balance between Earth absorption of solar energy and emission of radiation to space.


The Earth Energy Balance is a fundamental climate measurement that has been monitored from space for over 40 years. Microfabricated, absolutely calibrated bolometers with vertically-aligned carbon nanotubes that are developed by this project provide a more accurate and more compact method for measuring both the solar energy arriving at the Earth and the reflected and emitted energy leaving the Earth. NIST bolometers have measured the energy from the sun from space on the Compact Total Irradiance Monitor and the Compact Spectral Irradiance Monitor . NIST bolometers will measure the energy leaving the Earth on the Libera mission, expected to launch in 2027.

The project is also developing the technology for linear arrays of broadband, absolute microbolometers to provide high spatial resolution capability to measure the impact of cloud variability on the Earth’s Energy Balance.

Detectors built for the Libera mission will be used to maintain the decades-long Earth Radiation data record with improved accuracy.
Credit: Nathan Tomlin/NIST
A 1x32 linear array of microbolometers with vertically-aligned carbon nanotube absorbers is under development at NIST to enable study of the impact of cloud-radiative forcing on the Earth Energy Budget at 1 km spatial resolutions.
Credit: Chris Yung/NIST

Project Publications

Created December 16, 2022, Updated February 22, 2023