Read here. The Armagh Observatory in Northern Ireland has maintained one of the oldest temperature databases. From the www.junkscience.com site we know the following:
- Armagh Observatory: The observatory is still largely surrounded by countryside similar to that which has existed since its foundation in 1790. Together with the fact that the population of Armagh when compared with other Irish and UK cities has increased relatively little since the late 18th and early 19th centuries (population 1816: 7,000; 1911: 7,600; 1991: 14,265), its rural environment has ensured that the observatory suffers from little or no urban micro-climatic effects. In addition, with a relatively exposed site, in a fairly windy maritime climate, any urban climatic effects that did exist would be expected to be minimized.