> it's taken into consideration
Since the paper doesn’t say this, I assume you’re one of the researchers or associated with them? Do you mind sharing some details about how it’s taken into consideration?
Since the paper doesn’t say this, I assume you’re one of the researchers or associated with them? Do you mind sharing some details about how it’s taken into consideration?
here's one of them : https://link.springer.com/article/10.1007/s00484-009-0272-x
The historical Japanese calendar suffered from drift away from seasonal events because the months had either 29 or 30 days in them, but the actual lunar calendar is 29.53... days long. This was a known problem, and they would occasionally add a 13th month to the year to compensate, but this was only done when either the Emperor died, or when the Emperor said to do it (usually to commemorate some significant battle). Both of those situations means that the leap months were not added in a systematic way, so trying to back-calculate dates has errors. Several attempts have been made over the last 75 years by scholars to create conversion tables for this, but they all have errors and can be inaccurate up to 4 weeks.