If climate change were visible at that scale (tiny resolution between 0 and 40 degrees) we'd be all boiled since a while.
Still, you can see signs: the maximum temperature until 1990 or so seems to be around 35 degrees, since then there are several peaks above that value and in 2016 (?) it looks to be 38-39. It's certainly less visible on the peaks in the low, because maybe the absolute lowest scores appear to be in the 1990-2000 decade, but then again, all years in the 2010-2020 decade seem to be slightly higher than the minimum temperature in any other decade.
That said, there is massive downscaling involved in such scale, so I wouldn't be too surprised if some details were just skipped and not visible. I wouldn't trust this interpretation much - if a visualization it needs to be, I'd rather plot a moving average with a window of 6 months at least (or even 1 year to entirely rule seasonalities out), and see if that one has an upward trend or not (I bet it does).
[EDIT] I now see the post below with the year averages since 1979. It does indeed seem that 1995-1997 were abnormally cold years, and also that 2010-2020 is the warmest decade since then (and likely since quite a bit longer). So the outliers analysis here above seem to stand :-)
Tech lead for WEMC here - see https://tealtool.earth Straightforward charts of climate related data for different countries and regions around the globe
For temperature and a few other variables, it shows historical data from the EU Copernicus service (C3S) along with three different projected series out to 2100
for CO2, it shows the latest historical data
The charts are concerning and I am sure my co-workers are not hell bent on faking data to scare people just to get more funding; they work too much and go to too many meetings.
I have not analyzed any data yet and the purpose of plotting the time series was to show an example of the data as a function of time. As others have already mentioned, the swing in Durban temperatures over the seasonal cycle is ~25°C while global temperature increases due to climate change so far are on the order of 1°C.
Plus weather data tends to be quite noisy, just think how variable the weather can be day-to-day and we're squishing 80 years of that into one plot. Also worth noting that different places may experience climate change differently. Some places may be the average temperature go up, some maybe only in the summer, so you'll have to look at averages. Some places may see more extreme summer highs, so then you can't just look at averages but the average extremes or the tail end of the temperature distribution.
So it'll be hard to discern any climate change from just a cursory glance. I'm not saying it's there, just that it requires more analysis.
Still, you can see signs: the maximum temperature until 1990 or so seems to be around 35 degrees, since then there are several peaks above that value and in 2016 (?) it looks to be 38-39. It's certainly less visible on the peaks in the low, because maybe the absolute lowest scores appear to be in the 1990-2000 decade, but then again, all years in the 2010-2020 decade seem to be slightly higher than the minimum temperature in any other decade.
That said, there is massive downscaling involved in such scale, so I wouldn't be too surprised if some details were just skipped and not visible. I wouldn't trust this interpretation much - if a visualization it needs to be, I'd rather plot a moving average with a window of 6 months at least (or even 1 year to entirely rule seasonalities out), and see if that one has an upward trend or not (I bet it does).
[EDIT] I now see the post below with the year averages since 1979. It does indeed seem that 1995-1997 were abnormally cold years, and also that 2010-2020 is the warmest decade since then (and likely since quite a bit longer). So the outliers analysis here above seem to stand :-)