"Qualitative" is usually opposed to "quantitative". But consider the following sentence:
Varying the CO2 emissions in climate models has a qualitative effect on the predictions of future weather conditions.
Could "qualitative" also mean "significant" in this context?
I think I have seen several examples of this kind, where the word "qualitative" is used even when the effects have been quantified. Since it is in the field of research, I wonder if the meaning could really be "significant" sometimes, or if it is just due to the tendency of researchers to stay very careful about the meaning of the results they find.