To me it's just three lines trying to find a good guess with highly manipulated surface temp data.... (climateaudit.org)
I highly recommend visiting Tony Heller's site «Real Climate Science» for a comprehensive understanding of the blatant manipulation of NASA's GISS temp data set to fit the global warming narrative. (climatism.blog)
I used 360 points on the X axis because this broadly corresponds to the number of months of satellite global mean temp data available (around 30 yrs times 12 mths), but this can be changed also. (climateaudit.org)