Earth's albedo variations 1998–2014 as measured from ground‐based earthshine observations

• Published in: Geophysical research letters 2016-05, Vol.43 (9), p.4531-4538
• Main Authors: Palle, E., Goode, P. R., Montañés‐Rodríguez, P., Shumko, A., Gonzalez‐Merino, B., Lombilla, C. Martinez, Jimenez‐Ibarra, F., Shumko, S., Sanroma, E., Hulist, A., Miles‐Paez, P., Murgas, F., Nowak, G., Koonin, S. E.
• Format: Article
• Language: English
• Subjects: aerosol; Albedo; Albedo (solar); Albedo variations; Anomalies; Climate; Clouds; Cycles; Earth; Earth albedo; Earth science; earthshine; Evolution; Geophysics; Ground-based observation; Instruments; Meteorology; Moon; Photometry; Radiation; Radiation budget; Space stations
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2016GL068025

The Earth's albedo is a fundamental climate parameter for understanding the radiation budget of the atmosphere. It has been traditionally measured not only from space platforms but also from the ground for 16 years from Big Bear Solar Observatory by observing the Moon. The photometric ratio of the dark (earthshine) to the bright (moonshine) sides of the Moon is used to determine nightly anomalies in the terrestrial albedo, with the aim of quantifying sustained monthly, annual, and/or decadal changes. We find two modest decadal scale cycles in the albedo, but with no significant net change over the 16 years of accumulated data. Within the evolution of the two cycles, we find periods of sustained annual increases, followed by comparable sustained decreases in albedo. The evolution of the earthshine albedo is in remarkable agreement with that from the Clouds and the Earth's Radiant Energy System instruments, although each method measures different slices of the Earth's Bond albedo. Key Points We presente a new 16 year long global albedo record (a fundamental climate parameter) taken using the earthshine methodolgy The Earth's reflectance presents decadal variability, but overall no long‐term trend is identified The new data seem to agree well with the only other available albedo data set, the one from CERES instrumentation