Here’s the thing: It probably isn’t perceptible to the instruments, either.
I know Tony Watts is not an unbiased source, but he’s all I have. His blog contains this recent guest review of a Jun 2023 study of the accuracy of liquid-in-glass thermometers upon which the global historical temperature record is based. The review — if you can wade through it — is an eye-opener, however polemical its tone may be.
The gist, as I see it, is this: You want to say we know air-over-land temps from the late 19th century to within less than .2°C? You can’t because the slop in instrumental readings from that period is probably more than double that.
You want to say that the global temperature today is 1°C hotter than the twenty-year average? You can’t because the uncertainty of measurement is — to this day — still nearly 2°C largely because of the reliance of sea-surface temp readings on liquid-in-glass thermometers.
“The lengthened growing season, the revegetation of the far North, and the poleward migration of the northern tree line provide evidence of a warming climate. However, the rate or magnitude of warming since 1850 is not knowable.”
Unprecedented warming is a really fraught message, given the uncertainty of the underlying measurements and will be ever thus.
The problem of concentrating with this point is that one should wonder why it is that the readings did go just one way, when logically it would have gone up or down, and in essence the average would show the most probable temperatures from those days.
Incidentally, Tony Watts is also an expert of not telling others that many times the climate researchers are aware of the problems and correct for them… leading Watts and others to accuse researchers of adding temperature, when many times the adjustments (that still show the big problem we are into) lower the temperature, just not enough to counter that the warming is still taking place. You can’t win with that crowd, climate contrarians like to keep on being contradictory too.
There is overwhelming evidence that humans are the dominant cause of the recent global warming, mainly due to our greenhouse gas emissions. Based on fundamental physics and math, we can quantify the amount of warming human activity is causing, and verify that we’re responsible for essentially all of the global warming over the past 3 decades. The aforementioned Foster and Rahmstorf (2011) found a 0.16°C per decade warming trend since 1979 after filtering out the short-term noise.
In fact we expect human greenhouse gas emissions to cause more warming than we’ve thus far seen, due to the thermal inertia of the oceans (the time it takes to heat them). Human aerosol emissions are also offsetting a significant amount of the warming by causing global dimming. Huber and Knutti (2011) found that human greenhouse gas emissions have caused 66% more global warming than has been observed since the 1950s, because the cooling effect of human aerosol emissions have offset about 44% of that warming.
I’m in Florida, where I was born and raised. I do not like it here. And part of the reason is the summer. I’m at least lucky to be in the gulf side, near Tampa, instead of down south where I lived as a kid. There’s usually a slight reduction in heat as you venture north, but it’s already stifling here. Even early mornings, when the sun isn’t really up yet, are gross. It’s not just the heat, it’s also the humidity (I’ve long described Florida as paved over swamp land)
And we should expect a lot of big and strong hurricanes this season. Hot water embiggens them.