There is no evidence, that this part - time and locally restricted effect has any significant effect on global temperature. (realclimate.org)
While these adjustments don't have a big effect on the global temperature record, they are needed to obtain consistent local records from equipment which has changed over time. (skepticalscience.com)
Recent research indicates that global albedo is fairly constant, and having no material effect on global temperatures. (skepticalscience.com)