At the bottom right of the chart there is a rise in the average temperature (warming) from -32 degrees C. to almost -31.5 degrees C. as of the year 2000, derived from Greenland ice core studies.
The margin of error has to be at least +/- 1 degrees F. for that section of the chart, so the warming is within the margin of error of the measurements (but forget about that for now -- let's assume the +0.5 degrees C. warming is correct).
The small rise of the average temperature since the 1800s moves us away from cold weather in the prior Little Ice Age period.
That means the warming is good news, and lets hope for more warming -- even after the warming we are still near the coldest average temperature in the past 10,000 years!