It's easy to explain to a skeptic

If you are skeptical. it's easy to show you why I suspect the climate data has serious issues.  For example, the GISS data does not match the Alaska climate data.  All stations except Barrow show cooling trend since 1979.  Barrow shows a warming trend.

GISS map showing Alaska annual trend for 1978-2013

Actual data from climate stations

A climate skeptic probably doesn't even need it explained.  A believer, it will not matter how carefully, how well, or how much evidence is used to explain.  They always have a way to avoid discussing, or even seeing the evidence.