:I am having a similar problem interpreting this sentence.  Normally, I would read "33 C° (59 F°)" as meaning 33 degrees celcius (which is equal to 59 degrees farhenheit), but this this is not a correct conversion.  
 ::This has been answered several times. The sentence says, "Earth's surface would average about 33 C° (59 F°) colder..." It is about a difference in temperatures.    

 ==C° notation== 
 I notice that the C° and  F° notation that we currently use was introduced by  in this edit. The Celsius article says, "This is sometimes solved by using the symbol °C (pronounced "degrees Celsius") for a temperature, and C° (pronounced "Celsius degrees") for a temperature interval, although this usage is non-standard." I have never seen this notation before, and I see that it has not stopped the steady flow of people either commenting here, or altering the article, because that sentence is still quite widely misunderstood. I wonder if we should put a little more effort into explaining what we're actually saying, rather than hoping that a non-standard (and to my experience, obscure) notation and hidden markup comment will do the trick?