Why Don't I Notice Global Warming?

We still have winter and summer. Why do I keep hearing that the Earth is warming if it's still getting cold and I can't tell that it's warming?

We experience weather daily. There are huge differences between night and day, winter and summer, etc. Where I live (Austin, TX), the typical range over a single year is ~90 degrees Fahrenheit. How would I notice if it's 2 degrees F hotter now than it was 50 years ago?

This is a signal to noise problem . We can notice it when frosts start later in the year and stop earlier in the year. We can see a change in when leaves fall. The actual temperature change is very difficult to perceive though.

To try to make it clearer, I put together some plots.

Here are the daily min temperature for the Denver, Colorado region from 1960 - 2009:

Did the average temperature change in that period? I have no idea from that plot. What if we just look at the difference from the average (anomaly)?

Here is the difference between the daily min temperature and the average daily min temperature for the 1951-1980 period:

Still no clue if the average temperature changed. Here is the same plot with a one-year moving average average plotted on top of it:

Still can't tell if there's anything there. Here is the same thing with the 10-year moving average plotted on top of it:

Maybe something tiny there? Let's zoom in. Here's just the 10-year moving average plot:

Clear trend now. The increase is absolutely there. The daily, seasonal, and yearly variance is way too high to perceive it directly though. Even seeing all the data at once in those first plots, it's impossible to make out clearly.

We have to rely on large-scale data collection and computer analysis over our guts on this one...

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