The proxies used for earlier measurements are very flawed. Typically, they use ice cores from Greenland or Antarctica (hard to get ice cores from other places due to the lack of long term ice). However, the CO2 levels at such high latitudes are significantly lower (due to increased absorption by cold oceans (solubility of CO2 varies with water temperature, see Henry's Law)) and the CO2 trapped in ice also dissolves out over time, leading to a lower measurement than was actually present. The presented CO2 concentration graphs are an abomination, they are created by splicing ice core data, atmospheric flask data taken in Antarctica (atmospheric CO2 at the poles is about 50ppm lower) and instrumental measurement from Manua Loa in Hawaii (being close to the equator, it has a high CO2 level due to warm oceans). Splicing proxy data with observational data is a big red flag in any supposedly scientific measurement. These measurements are often not comparable, particularly when the observational measurement is effectively an instantaneous measurement and the proxy has a resolution that may be measured in centuries.

A much better proxy is plant stomata density (https://www.geocraft.com/WVFossils/stomata.html) which shows that the CO2 concentration, though varying considerably over the short term (hundreds of years) has remained fairly consistent around the 350ppm range for the last 15000 years or so.

7% is actually significant in any balanced system, pull 7% out of annual rainfall in a given area and it will change the life it can support, throw a watch off by 7% and its time keeping is wrecked, same with the carbon cycle, at least when a volcano has a big ash spew it blots the sky and mitigates ground heating, just the clouds heat causing condensed water to pull the carbon therein out faster, our cleaner pollution doesn't induce an acceleration in the carbon cycle or cause a wash in heating and cooling.

Either Way we could pretty easily solve the so called greenhouse effect if we wanted, just pump the correct chemicals for the carbon and methane to bond to or breakdown, if a reaction to cause higher density occured they would simply fall out of the sky faster, this is already how the carbon cycle in the air works. Even just cloud seeding would pull atmospheric carbon down with rain.

Simple solution, figure out safe times of year to use haarp arrays to heat sea clouds in the remote parts of the ocean, hell, there are a few equatorial islands with no real population, make solar focusers out of mirrors and lenses to passively heat surrounding waters to increase sea humidity and cause a knock-on hot house rain effect, localized heating for global cooling, like I said, balanced system don't take much extra energy to tip, that's why cloud seeding works at all.

Bisecting australia with massive mobile strip mining vehicles already in country to for an inland sea would be about the cost of the unfinished southern border wall and it would produce grasslands and kelp ecosystems enough to offset australia, new zealand and all of south america.

Grasslands and rainforests are about equal in carbon sequestration after all the balance point is growing seasons hence why rainforests are good equatorial carbon sinks and grasslands are better for temperate zones.

The fact people are talking about pizza stoves and tiny homes and not the above things or plugging subterranean coal and gas fires like in pensylvania or greece says the whole thing is a put on for control.

When did direct measurements begin?