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Updated: Jul 10, 2026
06:27
Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
Changes in Earth's albedo measured by satellite.
Bruce A Wielicki1, Takmeng Wong, Norman Loeb
1NASA Langley Research Center, 21 Langley Boulevard, Hampton, VA 23681, USA. b.a.wielicki@nasa.gov
Science (New York, N.Y.)
|May 10, 2005
Summary
NASA satellite data show Earth's albedo remains within natural variability over the last four years. This contradicts previous moon-based observations, highlighting the need for longer satellite records to detect climate trends.
Area of Science:
- Earth science
- Climate science
- Satellite remote sensing
Background:
- Earth's albedo, the fraction of solar radiation reflected to space, is a critical climate indicator.
- Previous studies using earthshine observations suggested a significant increase in albedo.
Purpose of the Study:
- To analyze NASA's global satellite data on Earth's albedo.
- To compare satellite observations with earthshine-inferred albedo changes.
- To assess the current state of Earth's albedo within climate variability.
Main Methods:
- Utilized NASA global satellite data to measure Earth's albedo.
- Analyzed a four-year period of satellite observations.
- Compared findings with inferred albedo changes from lunar earthshine observations.
Main Results:
- Recent satellite data indicate Earth's albedo is within natural variability.
- The observed albedo changes over the last four years do not confirm the 6% increase suggested by earthshine data.
- Satellite records are currently too short to definitively identify long-term climate trends in albedo.
Conclusions:
- Current NASA satellite data do not support the previously inferred increase in Earth's albedo.
- Extended satellite observation records are necessary for robust climate trend analysis of Earth's albedo.
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