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Changes in Earth's reflectance over the past two decades
E Pallé1, P R Goode, P Montañés-Rodríguez
1Big Bear Solar Observatory, New Jersey Institute of Technology, 40386 North Shore Lane, Big Bear City, CA 92314, USA.
Science (New York, N.Y.)
|May 29, 2004
Summary
Earth's reflectance decreased from 1984 to 2000, then reversed by 2003. Understanding drivers of these changes is key for climate change assessment and prediction.
Area of Science:
- Climate Science
- Earth Science
- Atmospheric Physics
Background:
- Earth's global shortwave reflectance influences climate.
- Decadal changes in reflectance are observed but not fully understood.
- Accurate measurement of reflectance is crucial for climate modeling.
Purpose of the Study:
- To construct a proxy for Earth's global shortwave reflectance using satellite data.
- To analyze decadal trends in Earth's reflectance from 1984 to 2003.
- To investigate the reversal of reflectance decline observed after 2000.
Main Methods:
- Correlating earthshine measurements with satellite observations of cloud properties.
- Developing a proxy measure of Earth's global shortwave reflectance.
- Analyzing time-series data from 1984 to 2003.
Main Results:
- A proxy measure revealed a steady decrease in Earth's reflectance from 1984 to 2000.
- A significant drop in reflectance occurred after 1995.
- Earthshine data from 2001-2003 indicated a reversal of this decline.
Conclusions:
- Observed decadal changes in Earth's reflectance highlight the need for further research.
- Understanding the drivers (natural variability, forcing, feedbacks) is fundamental for climate change assessment.
- Accurate climate change prediction relies on comprehending these reflectance variations.
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