Here's an overview of the adjustments that get made to climate data, from a "it doesn't really affect the overall trends you dumb skeptics" point of view:
No it doesn't. Very few "climate change skeptics" deny the climate changes. That's a very weak position and changes can be easily seen in almost any data set.
Climate change denialism is a strawman position, designed specifically to sound extreme in order to stop people getting curious and investigating the real beliefs of these bloggers.
https://www.sourcewatch.org/index.php/Anthony_Watts
https://mediabiasfactcheck.com/watts-up-with-that/