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• Albedo is not modified by the diurnal variation in solar zenith angle.
• Surfaces are assumed to be horizontal so no account is taken of land orientation or slope. 
• Differences in albedo that are not captured by the forecast (e.g. in mountainous areas or where observed conditions vary from forecasts).
• The albedo chart is purely climatological and anomalous conditions are not indicated.
• Albedo can be affected by melt ponds over polar sea ice sheets and extent of ice differing from climatology.
• Widespread anomalous snowfall (increase of albedo) or snowmelt (decrease of albedo) will change the heat energy available to the varying surfaces.
• Transitory local but significant variations in surface characteristics (e.g. extensive burnt vegetation, seasonal variation in lake extent) are not represented.
• Tides can cover and uncover extensive areas of sand or mud (e.g. around the Frisian Islands) or the extent of a lake can vary substantially during the year (e.g. Lake Kati Thanda–Lake Eyre, Australia).

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