Albedo reflectance and bi-hemispherical reflectance (e.g.,). These calculations are based on the bidirectional reflectance distribution function (BRDF), which describes how the reflectance of a given surface depends on the view angle of the observer and the solar angle. BDRF can facilitate translations of observations of reflectance into albedo. Earth's average surface temperature due to its albedo and the greenhouse effect is currently about 15 °C. If Earth were frozen entirely (and hence be more reflective), the average temperature of the planet would drop below −40 °C. If only the continental land masses became covered by glaciers, the mean temperature of the
Albedo 0.39 track, "Albedo 0.39" is an atmospheric track building on waxing and waning synthesizer chords and arpeggios, while a voice, reputedly the album's engineer Keith Spencer-Allen, narrates various physical properties of the Earth, such as its mass, length of the year in various measurements, and, finally, its albedo. Mike DeGagne of Allmusic described the tracks as "mesmerizing trips of assorted rhythms that include elements of jazz and mild rock", that along with "Albedo 0.39", "the two parts of "Nucleogenesis" are among the strongest cuts that keep his cosmic theme from deviating, while the livelier "Pulstar" involves some impressive instrumental range and