Humans have caused 1.5 °C of long-term global warming according to new estimates

Long-term should be defined. We can cool the planet the same amount long-term. Why is it taken as a given that any warming is irreversible when we have historical natural patterns showing global cooling (ice age)?

The damage to ecosystems, flora and fauna populations, etc etc, isn't reversible like that. Extinct species don't just bounce back, sadly.

Of course it can be reversed, it’s just vastly more expensive to do so. If your house is on fire and you don’t have insurance you don’t say “eh I can just build a new one”, you put the fire out.

Previous warming periods moved much slower. We are currently seeing the fastest rise in temperatur ever observed. We are already in a new extinction era as most species can not adapt fast enough to the changing climate.

I agree that warming is an important issue to address. I don’t agree that we know that it will be more expensive to cool. Space is cold and technology allowing heat to vent into space may be less expensive than we think.

Sure it's more accurate to say current known methods are expensive or have side effects. For example, Carbon capture is very expensive. Another example, is sulfur dioxide provides reflective properties which was artificially cooling the earth (from shipping exhaust) until it was banned because it causes acid rain and a host of health problems.

We'll probably find other interesting geo-engineering techniques over time, but it is very unwise to bank on future solutions. Many things, like nuclear fusion, have been "just around the corner" for years and years.

Climate change is accelerating at a rapid pace. Go look at a chart of CO2 emissions over time. I think people default to thinking we're in some stable or slow state, when we're far from it. We're not just increasing CO2 emissions, we're increasing the rate of emissions. Debt (tech, financial or otherwise) when you have a path to pay it off is a useful tool, but taking climate debt with no known good solution is very unwise.

There are changes that are irreversible in human time. For example the Greenland Glaciers were formed during an ice age but stable in pre industrial climate. Too much thawing would cause the entire tectonic plate to rise, raising the top of the glacier into a region of warm air that will melt it even if pre industrial temperatures are achieved again.

Greenland Glaciers have the surface area of Texas while being multiple kilometres thick. It alone is enough to cause sea-level rise of multiple metres. Also, melt water ingress into the Labrador sea might stop AMOC downwelling and could stop the gulf stream. All this would be irreversible during many human lifetimes.

I see your point. You assume though that the taking on of the debt will lead to the solution. I disagree. Its extremely unclear.

The transition away from CO₂-emitting technologies is already underway, driven by market forces alone—solar power, for example, is now cheaper than oil. Proposing a substantial increase in global debt to further accelerate climate initiatives would need to demonstrate the following:

1. Spending Wisely: Invest in technologies that work and also do not introduce more problems.

2. Trusting Who Spends: Governments or others must use funds on solving the issue (not just giving money to cronies).

3. Global Cooperation: Countries working together (does Russia who sees warming as helpful comply).

4. Dealing With Inflation: The plan should address the inflation it causes, as it will raise living costs for people already struggling.

5. Better Use of Funds: Proving this use of funds is better than spending on other global issues.

> I don’t agree that we know that it will be more expensive to cool.

This is not an agree or disagree situation. This is "I haven't googled it"

You're asking for a nearly insurmountable burden of proof before you'll believe one side (stopping global warming as was already agreed upon in Paris like a decade ago) but not the other

I believe we are more aligned on this issue than it might seem from this exchange. Like you, I value sustainability and recognize the importance of nature for both physical and mental well-being. Living near sea level, I experience the direct effects of climate impacts.

I also use air quality monitors to track CO₂ levels at home and in my office. (As a side note, I think more people should pay attention to indoor carbon emissions; in many offices and fitness centers, CO₂ levels can rise to an healthy amount)

While the suggestion about printing $100T to $200T is thought-provoking and is intended to address pressing global issues, I also consider the outcomes of similar actions during COVID. The significant money printing at that time—though aimed at stabilizing the economy—contributed to inflation and widespread challenges. I think we both share a desire to find solutions that address these needs without exacerbating suffering.

There maybe a misunderstanding here. The only debt I talked about was referring to carbon. We are enabling our current lifestyles by taking on carbon debt, which we will pay in climate change unless we pay off the principal (sequestration). You were speculating that some unknown future tech could make paying off that debt easier and cheaper, and I was pointing out that taking on debt without a current method of repayment is unwise. Since you appear hesitant about excess government debt I would expect you to be More not Less hesitant of debt we have no acceptable way to payoff, yet we are taking on more and more.