Where has climate changed? ...
AGW Theory is rather broad and all-encompassing ... some parts are easily demonstrated, clear cut a forest and pave with asphalt ... this "urban heat island" effect is well entrenched in science and this heating is strictly caused by human activities ... I'll leave it to you to research how deforestation is demonstrated to cause heating due to man's hand ... these parts of AGW Theory are confirmed to be true ...
I know you mean the CO2 component ... and we do have CO2's emission spectrum which clearly shows her "theoretical" ability to warm the atmosphere ... the question is "how much"? ... as far as I know, there is no way to demonstrate how much warming we should see right now ... we'd need to spend more money on better thermometers ...
We have qualitative evidence of CO2 warming the planet ... and you'd know that's valid science if you've taken a chemistry class ... that's a legendary experiment at all the Colleges of Science in all the world's universities (that have a separate College of Science) ...
Homework for today: Pick any point on the surface of the Earth, tell me what the climate was 100 years ago, what the climate is today, and what the climate is expected to be 100 years from now ... if all three are the same, then nothing has changed ... and if this is true for all the points on the Earth's surface, then climate isn't changing anywhere ...
It's a hoax ... climate hasn't changed in central North America in 100 million years ... even the Great Inland Sea experienced rain equally throughout the year, exactly like our Midwest today ... and for the exact same reasons ...