I am experiencing some differences between database and software versions when I calculate Global Warming Potenial using IA CML-basline for 1m2 glued laminated timber using the dataset "glued laminated timber, for indoor use - RER".
When performing the calculation in openLCA v1.7.2 using Ecoinvent 3.2 I get a negative kg CO2 eq (approximately -1400 kg CO2 eq.) due to CO2 that is stored in the wood. However, when I use openLCA v1.9 and Ecoinvent 3.4 I get a positive kg CO2 eq. (approximately 200 kg CO2 eq).
Why is there such a big difference between the two?