Papers on the albedo of the Earth

This list of papers contains observations of Earth’s albedo, concentrating especially on the possible changes in albedo. The list is not complete, and will most likely be updated in the future in order to make it more thorough and more representative.

UPDATE (November 4, 2009): Loeb et al. (2007) and Loeb et al. (2007) added, thanks to John Cook for pointing them out, see the discussion section below.

Inter-annual variations in Earth’s reflectance 1999-2007 – Palle et al. (2008) Doesn’t find much trends in albedo, although emphasizes a brief 1.5 year long increase in reflectance. “In the common period, earthshine, CERES along with ISCCP-FD data show a trendless albedo. However, preceding CERES, earthshine and ISCCP-FD reflectances show a significant increase before flattening and holding the increase.” [Link to PDF]

Variability in global top-of-atmosphere shortwave radiation between 2000 and 2005 – Loeb et al. (2007) “The ground-based Earthshine data show an order-of-magnitude more variability in annual mean SW TOA flux than either CERES or ISCCP, while ISCCP and CERES SW TOA flux variability is consistent to 40%. Most of the variability in CERES TOA flux is shown to be dominated by variations global cloud fraction, as observed using coincident CERES and MODIS data. Idealized Earthshine simulations of TOA SW radiation variability for a lunar-based observer show far less variability than the ground-based Earthshine observations, but are still a factor of 4–5 times more variable than global CERES SW TOA flux results. Furthermore, while CERES global albedos exhibit a well-defined seasonal cycle each year, the seasonal cycle in the lunar Earthshine reflectance simulations is highly variable and out-of-phase from one year to the next.”

Multi-Instrument Comparison of Top-of-Atmosphere Reflected Solar Radiation – Loeb et al. (2007) “Observations from the Clouds and the Earth’s Radiant Energy System (CERES), Moderate Resolution Imaging Spectroradiometer (MODIS), Multiangle Imaging Spectroradiometer (MISR), and Sea-Viewing Wide-Field-of-View Sensor (SeaWiFS) between 2000 and 2005 are analyzed in order to determine if these data are meeting climate accuracy goals recently established by the climate community. The focus is primarily on top-of-atmosphere (TOA) reflected solar radiances and radiative fluxes. … The results presented in this study are in stark contrast to those of Pallé et al. (2004, 2005) who claim to have observed a 6 Wm^-2 increase in annual mean reflected solar radiation between 2000 and 2003 based on Earthshine measurements. … When the global monthly anomalies in CERES Terra SW TOA flux in Fig. 9b are averaged annually, the difference between the minimum and maximum yearly anomalies is 0.6 Wm^-2, an order-of-magnitude smaller than the change found in the Earthshine data. Given the remarkable consistency shown here between data records from CERES, MODIS, MISR, SeaWiFS and ISCCP, none of these additional data records support a 6 Wm^-2 change between 2000 and 2003.” [Link to PDF]

Comment on ‘‘A multi-data comparison of shortwave climate forcing changes’’ by Pallé et al. – Bender (2006) Gives a nice overview to different albedo measurement techniques while commenting on Pallé et al. work. [Link to PDF]

22 views of the global albedo—comparison between 20 GCMs and two satellites – Bender et al. (2006) Compares climate model simulations to real world observations of Earth’s albedo. “Discrepancies between different data sets and models exist; thus, it is clear that conclusions about absolute magnitude and accuracy of albedo should be drawn with caution.” [Link to PDF]

Changes in Earth’s Albedo Measured by Satellite – Wielicki et al. (2005) “The satellite data show that the last four years are within natural variability and fail to confirm the 6% relative increase in albedo inferred from observations of earthshine from the moon.” [Link to PDF]

Changes in Earth’s Reflectance over the Past Two Decades – Palle et al. (2004) “This proxy shows a steady decrease in Earth’s reflectance from 1984 to 2000, with a strong climatologically significant drop after 1995. From 2001 to 2003, only earthshine data are available, and they indicate a complete reversal of the decline.” [Link to PDF]

Earthshine and the Earth’s albedo: 2. Observations and simulations over 3 years – Pallé et al. (2003) “Since late 1998, we have been making sustained measurements of the Earth’s reflectance by observing the earthshine from Big Bear Solar Observatory. … We find that our precision, with steady observations since December 1998, is sufficient to detect a seasonal cycle.”

Earthshine and the Earth’s albedo: 1. Earthshine observations and measurements of the lunar phase function for accurate measurements of the Earth’s Bond albedo – Qiu et al. (2003) “We have been making sustained observations of the earthshine from Big Bear Solar Observatory in California since late 1998. We also have intermittent observations from 1994–1995. Here, we develop a modern method of measuring, instantaneously, the large-scale reflectance of the Earth.” [Link to PDF]

Estimate of top-of-atmosphere albedo for a molecular atmosphere over ocean using Clouds and the Earth’s Radiant Energy System measurements – Kato et al. (2002) “The shortwave broadband albedo at the top of a molecular atmosphere over ocean between 40°N and 40°S is estimated using radiance measurements from the Clouds and the Earth’s Radiant Energy System (CERES) instrument and the Visible Infrared Scanner (VIRS) aboard the Tropical Rainfall Measuring Mission satellite.”

Earthshine observations of the Earth’s reflectance – Goode et al. (2001) “Regular photometric observations of the moon’s “ashen light” (earthshine) from the Big Bear Solar Observatory (BBSO) since December 1998 have quantified the earth’s optical reflectance. We find large (∼5%) daily variations in the reflectance due to large‐scale weather changes on the other side of the globe. … However, we find seasonal variations roughly twice those of the simulation, with the earth being brightest in the spring.”

Global change and the dark of the moon – Flatté et al. (1992) This is largely a review article. “We have considered the possibility of using earthshine to measure the reflectance properties of the earth (albedo and phase function). Measurements of earthshine carried out by Danjon in 1926-33 show that even then the average albedo could be determined with a precision of +/- 0.01 and that both synoptic and seasonal variations could be observed clearly. We show that, after correction for wavelength dependence and the opposition effect in the lunar reflectance properties, Danjon’s visual albedo of 0.40 can be reconciled with the ERBE satellite Bond albedo of 0.30.” [Link to PDF]

Repetition of Danjon earthshine measurements for determination of long term trends in the earth’s albedo – Huffman et al. (1990) “The authors are investigating the possibility of determining whether changes have occurred in the albedo of the earth due to changes in cloud properties. The method is to reproduce as faithfully as possible the measurements of earthshine made by André Danjon during the period from 1926 to 1935 and continued by J. Dubois from 1940 to 1960. To this end a “cat’s eye” photometer similar to that used by Danjon has been constructed and data taking begun. Analysis for long term trends depends on understanding of geographic effects, seasonal variations, and 10 year variations in earthshine.”

Albedo, color, and polarization of the Earth – Danjon (1954), in The Earth as a Planet, edited by G. P. Kuiper. Presents early albedo measurements by earthshine.

The albedo of the planet Earth and of clouds – Fritz (1949) “The albedo of the whole earth is calculated to be 35 per cent, largely on the basis of Danjon’s visual lunar measurements. The calculations also give a value of about 0.50 for the average albedo of clouds, which is in better agreement with measurements than the currently accepted value.”

Sur l’albedo de la terre – Dubois (1947). (I haven’t found suitable link for this one but some details are given in Qiu et al., 2003, see above.) Presents early albedo measurements by earthshine.

Recherches sur la photométrie de la lumiére cendrée et l’albedo de la terre – Danjon (1928). (I’m not certain that the linked paper is correct, but both the name and the journal reference seem to be similar to what is given in Qiu et al., 2003, see above, they also give some details on this. See also Flatté et al., 1992 for details on this.) Presents early albedo measurements by earthshine.