There is a government center in Boulder, Colorado. They get literally tons of cash to conduct research. They put out government contracts to build and take data from thousands of data gathering centers.
Here is the problem:
The government contract require weather data gathering to be built to a very tight specification
The contracts go out to the typical good-old-boys, political favorites
There is no quality control for the construction
The scientist job is to take data, process data, and state results. Government workers don't care about the data quality. The photos will explain.
This article is for people that understand that taking measurements requires some, even a tiny level of controlled environments and requires maintaining a controlled system.
Over the years, volunteers photographed and documented every weather measurement station. It is in a database for public view.
Note: about 1/3 were not built to requirements. Example: never put on or 400 feet away from pavement, or near an air-conditioner exchange vent, or … the list goes on.
Nobody but volunteers Quality Assured these. So, big surprise, government contractors didn't follow the specification.
Look at the photos, these are fair representations of good installations and bad installations. About 1/3 are bad if you care enough to go through the entire database of photos and understand the methodology.
If you don't believe in the Scientific Method, then this highly documented research won't matter anyway. This lead to a statement:
U.S. Office of the Inspector General
Lack of oversight, non-compliance and a lax review process for the State Department’s global climate change programs have led the Office of the Inspector General (OIG) to conclude that program data “cannot be consistently relied upon by decision-makers” and it cannot be ensured “that Federal funds were being spent in an appropriate manner.”