Climate Change, page-187

Because your ice core graph seen below, is for one location (Greenland)

And as I explained in the response ( go back a few comments) this graph ends in 1855, not present day 2023 (or 2009). This graph looks as if it was adapted from the source which I posted in my response to you where the author confirmed that the ice core data ends in 1855 and does not take into account the last 170~ years of warming. So it is misleading. Paleoclimate conventions used 1950 as the present, and the author of the paper which this graph is adapted from confirms that the last GISP2 reading was from 1855.

That's why our graphs look different.

If you go to 4:30, you can see a very good response to someone that made the exact same mistake. You only need to watch for about 5 minutes.