Yeh, the “tropical thing” people don’t like. I bring it up to point out warm climate isn’t as dangerous to humans as they are led to believe. I’m not making the argument population growth in tropical areas is driven by temperature directly. I’m just pointing out if humans can’t stand warm climates the population couldn’t explode there. Especially as many of those areas use very little energy to modify their environment. Humans (from mammalian speciation on) evolved primarily in climates as warm or warmer than today. For context for what follows we are at 423 ppm atmospheric CO2 and 15°C average global temp today. When mammalian evolution occurred the atmospheric CO2 level fluctuated between 2500 and 1000 ppm and was on the high side of that range when mammalian speciation began. The average global temperature during that time period varied between 25°c and 17°C, again, with mammalian speciation beginning at the high end. When primates split from other mammals in their evolution the global temperatures were still in the 25°C range and CO2 was around 1000-1500 ppm. These primates developed the ability to sweat to a small extent, but the more efficient human sweating physiological response to deal with heat developed around 2 million years ago. My only point with the tropics is the fact humans thrive there without great energy inputs is evidence we have conserved genetics shaped by eons of living and evolving in hotter temps than we see today—by far. Of course societal and social issues are involved in population growth in the tropics. I agree with that. But if warm climate was truly detrimental to human survival and rapid reproduction, we couldn’t observe survival and the most rapid reproduction in the hottest places on the planet—without massive energy inputs. It’s an argument based on logic as much as biological science. It’s a logical point of reference on human relationship to temperature when science and logic are followed instead of news headlines and political rantings.
So, this is supposed to be the subject for discussion: "Climate deniers don't deny climate change any more. Has anyone ever denied that climate changes?
So what scientific evidence do you have to support your claim that burning fossil fuels doesn't produce carbon dioxide?
Hmmmm!!! I'm not interested in the CO2 level and global temperatures in 1500 BC, but only in the causes of the recent global temperature rises and the results and analysis of the data from your scientific research and why atmospheric CO2 has risen over the last 50 years. And what is the evidence from your scientific research that the biosphere has expanded and produced more CO2 instead of reducing it, and is that because there are more humans producing CO2 from burning fossil fuels?
I hate to say it, but that's a really dumb question. Burning anything produces CO2. It, along with water, are the desired byproducts of combustion. Engine exhaust is, by definition, about 30% CO2, 30% H2O, and 40% Nitrogen (which also happens to be 78% of the entire atmosphere) as well as a vanishingly small bit of actual pollutants that result from mechanical limitations of a whole bunch of fast changing temperatures and pressures in the combustion chamber. So, what scientific evidence do you have that you know anything at all about what you're harassing others about?
In other words let’s invoke Brandolinis law and sit back and watch others do the work whilst your contribution is to do a quick search of denialist websites and slap down the first vaguely relevant piece you can find
None of that, however, changes the fact that recent global warming from the increase in atmospheric CO2 is caused by human activity.
That’s approx 1/5 of the cause of CO2 rise (if you want supporting research on this post some in your response and I will answer like for like
IOW the recent global warming from the increase in atmospheric CO2 is caused by human activity, including the burning of fossil fuels. Even though some think that the recent increases in atmospheric CO2 is only caused by burning tropical rainforests.
Sorry, but you're shooting behind the duck. His questions were already answered and a link to supporting peer-reviewed research was already provided. I have no obligation to answer twice.
Actually, it directly refutes that claim. The conclusion of the research is that increased atmospheric CO2 was not produced by human activity.
I doubt anything posted was truly “peer reviewed”. Was it an actual research paper or just a cherry picked blog post?
Lols! You tempt me to make the effort to actually look for this mythical “proof” lols So what has been increasing atmospheric CO2 - green fairy farts?
So what scientific evidence do you have to support your claim that CO2 is not produced from human activity?
Rising temperatures caused the biosphere to generate increased CO2. From the conclusion (linked for your convenience) of Koutsoyiannis, 2024: In the 16th century, Earth entered a cool climatic period, known as the Little Ice Age, which ended at the beginning of the 19th century; Immediately after, a warming period began, which has lasted until now. The causes of the warming must be analogous to those that resulted in the Medieval Warm Period around 1000 AD, the Roman Climate Optimum around the first centuries BC and AD, the Minoan Climate Optimum at around 1500 BC, and other warming periods throughout the Holocene; As a result of the recent warming, and as explained in [5], the biosphere has expanded and become more productive, leading to increased CO2 concentration in the atmosphere and greening of the Earth [17,18,19,32]; As a result of the increased CO2 concentration, the isotopic signature δ13C in the atmosphere has decreased; The greenhouse effect on the Earth remained stable in the last century, as it is dominated by the water vapour in the atmosphere [31]; Human CO2 emissions have played a minor role in the recent climatic evolution, which is hardly discernible in observational data and unnecessary to invoke in modelling the observed behaviours, including the change in the isotopic signature δ13C in the atmosphere.
From the abstract (essentially the CO2 in our atmosphere is not the kind human activity produces): Abstract Recent studies have provided evidence, based on analyses of instrumental measurements of the last seven decades, for a unidirectional, potentially causal link between temperature as the cause and carbon dioxide concentration ([CO2]) as the effect. In the most recent study, this finding was supported by analysing the carbon cycle and showing that the natural [CO2] changes due to temperature rise are far larger (by a factor > 3) than human emissions, while the latter are no larger than 4% of the total. Here, we provide additional support for these findings by examining the signatures of the stable carbon isotopes, 12 and 13. Examining isotopic data in four important observation sites, we show that the standard metric δ13C is consistent with an input isotopic signature that is stable over the entire period of observations (>40 years), i.e., not affected by increases in human CO2 emissions. In addition, proxy data covering the period after 1500 AD also show stable behaviour. These findings confirm the major role of the biosphere in the carbon cycle and a non-discernible signature of humans.
Everything. The point of the paper is that CO2 produced by human activity is insignificant in the atmosphere.