#1-4 are observations at that specific location (Mauna Loa). CO2 has the most data because it was built by NOAA to monitor emissions of volcanic gases. In that same data, they noticed the trend of CO2 rising even when the volcano had no change. Realizing this wasn't just a fluke, they expanded the site to also measure CH4 in the early 80s. The two combined lead to the first...well...scare...that we may be heading for something bad. It lead to the creation of the IPCC and several climate studies. These studies eventually exposed CFCs as being bad for ozone, among other things, which resulted in SF6 being added to instrumentation in the mid 1990s. Then the bat-shit crazy phase was entered with Al Gore and the IPCC in the late 1990s which resulted in N2O monitoring being added in the early 2000s.
#5 are also observations taken by satellites and telescopes which the facility in Boulder, Colorado, collates and reports on.
#6 is the only graph that includes observations and modeled data. If you want the best data... here you go:
UAH =
University of Alabama in Huntsville which uses a variety of satellite measurements to infer surface temperature.
RSS =
Remote Sensing System satellites which use microwaves to measure atmospheric temperature.
As you can see...all are in agreement of warming. Which makes sense considering CO2, CH4, N20, and SF6 are rising too (all observations since the 1960s).
Millions of years ago:
That last is kind of the point: when CO2 was this high before, humans didn't exist. We're already in untested waters.
Note the bottom of that picture versus the CO2 level above--associates CO2 with glaciation. You can always reference this website to see what we're at now:
GML conducts research on greenhouse gas and carbon cycle feedbacks, changes in aerosols, and surface radiation, and recovery of stratospheric ozone.
www.esrl.noaa.gov
408.54 ppm is the September average.
Glaciers generally don't exist above ~500 ppm. It was about 310 ppm in 1920. In another century, we may cross 500 ppm which could translate to no more glaciers. A century. The children born today may see the day that glaciers don't exist. If that isn't a wake up call, what is?
Because it's true, CH4 is 300% higher than it was for millennia before and CO2 is ~150% higher than it was. You graph these trends and it turns into a hockey stick. Guess what's also a hockey stick. Human population:
Coincidence? Probably. Humans rely heavily on mechanization which is principally powered by compounding oxygen into carbon dioxide for energy. Hell, we couldn't sustain that population without mechanization.
I was a skeptic too (which
@magibeg can attest to) but, the evidence has become overwhelming in support of anthropomorphic warming in the last decade. I can find no other reasonable explanation despite years of trying. Sure, there's still question marks on some things like clouds but what needs to be done about it all comes back to one in the same: curb emissions.
I am not fatalist by any means. I think a large number of humans will survive whatever results from it. It's not like an asteroid or super volcano eruption. What concerns me is how many other species will we lose on the way; they can't adapt as fast as we can.