I used to live in Chicago. In 1980, the official weather monitoring station there was moved from Chicago's near-lakeside location at Midway Airport to the far inland location of O'Hare Airport. In the blink of an eye, the actual recorded temperatures for the city went up because, no longer, would the new temperature monitoring location at O'Hare be subject to the cooling lake breezes that had once affected the Midway location. Automatically, Chicagoans saw a local climate change without there actually having been one.
Where I live right now, Las Vegas, the temperature monitoring is being heavily influenced by the "mass" of concrete buildings and the heat absorption of the many blacktopped roads that have been increasing since it became a city; some 100 years ago. Buildings and roads are added structures that hold and retain heat. So, as a consequence, and through no actual change in climate, Las Vegas' official temperatures have had to inch upwards because of the shear expansion and growth of the area. I actually live only 7 miles north of the Strip and the temps here are between 5 and 7 degrees cooler; partly because of being at a higher elevation, but also, because there is less consolidated mass to retain the heat.
This same kind of thing has probably happened all over the world -- especially in the desert areas where light colored reflective sands and tan dirt have been replaced with black tarred roofs and asphalt roadways and the heat retaining mass of modern buildings.
This is why weather monitoring, using city data, in support of climate change is flawed. The fact that the heavier populated areas of the world are warmer may have little to do with CO2 and a lot more to do with growth and the relocation of official weather monitoring stations. Something that I thought you might want to think about when you hear those "stories" about how much warmer it is getting in all the major metropolitan cities throughout the world.