Is Global Warming a Hoax?

[wufwugy]

Sorry I misunderstood, then.

I still think my response applies to your attempt to shed light on this:


I don't believe you've demonstrated this, except in the description of economists' views at your university.

I don't think this has anything to do with climate science or the conclusions of climate scientists.

Can you connect the dots?

Have climate scientists demonstrated that humans are causing global warming? If the answer is "no", why is the number thrown around always something like "98% of climate scientists" believe in anthropogenic global warming?

[MadMojoMonkey]

Have climate scientists demonstrated that humans are causing global warming? If the answer is "no", why is the number thrown around always something like "98% of climate scientists" believe in anthropogenic global warming?

It doesn't take a climate scientist to acknowledge that greenhouse gasses are emitted on the planet due to human activity.

https://www.epa.gov/ghgemissions/sou...-gas-emissions

Note the non-0 values.

Any questions?

[wufwugy]

It doesn't take a climate scientist to acknowledge that greenhouse gasses are emitted on the planet due to human activity.

https://www.epa.gov/ghgemissions/sou...-gas-emissions

Note the non-0 values.

Any questions?

The geophysics on what happens with carbon is persuasive and it's ultimately the reason why I tend to side with the idea that AGW is probably a thing. But the idea that the climate is warming because of human emissions has not been rigorously shown AFAIK. Part of why I started this thread is because inferring that humans are causing global warming from the available statistics doesn't strike me as sound.

[Keith]

It doesn't take a climate scientist to acknowledge that greenhouse gasses are emitted on the planet due to human activity.

https://www.epa.gov/ghgemissions/sou...-gas-emissions

Note the non-0 values.

Any questions?

It would appear that is slightly/highly misleading as a link.Agriculture is down as 9% of greenhouse gas emissions in the US but I struggle to believe that that is a net figure after taking into consideration the co2 removed from the atmosphere by the crops photosynthesis removing CO2 from the atmosphere by converting co2 back to O2.

On a world scale ,chopping down rainforest to create temporary grassland for beef production in brazil is extremely shortsighted by removing the co2 consumers (plants) to replace them with co2 generators ( animals) before the grasssland becomes semi desert due to lack of shade/soil fertility. WOrldwide developed countries should be paying the rainforest regions to retain them rather than chopping them down to exploit short term mineral/tree wealth and very short term animal production.

[MadMojoMonkey]

ITT Keith shares his feelings:

It would appear that is slightly/highly misleading as a link.Agriculture is down as 9% of greenhouse gas emissions in the US but I struggle to believe that that is a net figure after taking into consideration the co2 removed from the atmosphere by the crops photosynthesis removing CO2 from the atmosphere by converting co2 back to O2.

On a world scale ,chopping down rainforest to create temporary grassland for beef production in brazil is extremely shortsighted by removing the co2 consumers (plants) to replace them with co2 generators ( animals) before the grasssland becomes semi desert due to lack of shade/soil fertility. WOrldwide developed countries should be paying the rainforest regions to retain them rather than chopping them down to exploit short term mineral/tree wealth and very short term animal production.

I embrace skepticism, but if you're not letting it lead you to new discoveries, then the sentiment this post is exactly the problem that scientists have to deal with.

Scientist: Here's the data.
Kieth: Yeah... but it feels wrong, so you're probably making it up.

Also, rain forests are cool and all, but phytoplankton is the dominant Oxygen producer of planet Earth.

[Poopadoop]

It would appear that is slightly/highly misleading as a link.Agriculture is down as 9% of greenhouse gas emissions in the US but I struggle to believe that that is a net figure after taking into consideration the co2 removed from the atmosphere by the crops photosynthesis removing CO2 from the atmosphere by converting co2 back to O2.

Not an expert, but I think the 9% has mainly to do with livestock and machinery. Don't think the crops are reducing photosynthesis more than the plants that were growing on that land before it was converted for agriculture.

For example, if you cut down a forest and plant corn is the result a net gain or net loss of vegetation? I would think loss...

On a world scale ,chopping down rainforest to create temporary grassland for beef production in brazil is extremely shortsighted by removing the co2 consumers (plants) to replace them with co2 generators ( animals) before the grasssland becomes semi desert due to lack of shade/soil fertility. WOrldwide developed countries should be paying the rainforest regions to retain them rather than chopping them down to exploit short term mineral/tree wealth and very short term animal production.

This seems to more or less contradict what you said above and agrees with what I said if I have it right.

[Keith]

Not an expert, but I think the 9% has mainly to do with livestock and machinery. Don't think the crops are reducing photosynthesis more than the plants that were growing on that land before it was converted for agriculture.

For example, if you cut down a forest and plant corn is the result a net gain or net loss of vegetation? I would think loss..

Agriculture has aggressively selected for increased yield for hundreds of years , so current cops are a lot better at light interception (selecting for greater leaf area usually called Leaf Area Index),higher growth rates from the light that is intercepted ( selecting genotypes that produce higher yield) and to a lesser extent selecting for harvest index (% of the crop that is the desired crop rather than unusable plant tissue) so that as a result , crops will typically have a lot more biomass production than unimproved native indiginous plants. increased biomass means increased co2 removed from the atmosphere.. You are also assuming that in pre industrial era that natural vegetation wouldn't produce co2 but uneaten vegetation would either die back /be shed as leaves and rot down by the soil bacteria and produce co2 that way.

As far as animals go , pre-industrial period , the central USA grasslands had millions of bison/horses that are no longer there, these will offset the current number of animals in animal production.

This seems to more or less contradict what you said above and agrees with what I said if I have it right.

with regards the rainforests, the vegetation is removing co2 from the atmosphere year on year with a high leaf surface area because of the age/size of the trees. In Brazil, the trees are typically being replaced with soya, or grassland to graze animals. that grassland probably has lower light interception than the preceding trees due to the lower leaf surface area but is eaten by animals that then respire some of the co2 captured by the grassland back out into the atmosphere reducing further the net amount of co2 removed from the atmosphere. those grasslands only have a limited lifespan as soil nutrients are used up , plant growth rate becomes limited, sun hitting the earth together with evapotranspiration from the grassland producing a soil moisture deficit leads to the grassland dieing off and semi desert conditions to arise which then means hardly any co2 gets removed from the atmosphere.
the carbon in the animals derives from plants that they have eaten and the carbon in the plants derives from the carbon removed from the atmosphere by photosynthesis.Animals therefore can't mean a closed system is a net producer of co2 as the carbon in the animals has come from the co2.The more animals there are however the lower net c02 removal from the atmosphere will be.

[Poopadoop]

Ok, but agriculture involves more than just crops and livestock sitting there on the land doing what they do.

The products need to be cared for, with pesticides (that are produced in fuel-burning plants), machinery (that burns fuel), and then transported and processed by more machinery (that burns more fuel). So just talking about what the plants and animals do is not describing the whole effect of agriculture on CO2.

It's a huge industry, and perhaps most if not all of that 9% increase ascribed to it is due to the fuel-burning machinery that supports it?

[Keith]

Ok, but agriculture involves more than just crops and livestock sitting there on the land doing what they do.

The products need to be cared for, with pesticides (that are produced in fuel-burning plants), machinery (that burns fuel), and then transported and processed by more machinery (that burns more fuel). So just talking about what the plants and animals do is not describing the whole effect of agriculture on CO2.

It's a huge industry, and perhaps most if not all of that 9% increase ascribed to it is due to the fuel-burning machinery that supports it?

the link that i gave MMM shows that atmospheric CO2 is plateauing due to plants taking up more co2 and converting it to biomass. Considering how much co2 is being pumped into the atmosphere by non agricultural means its difficult to see how total co2 is plateauing if agriculture is a net contributor of co2 to the atmosphere.

[Poopadoop]

Have climate scientists demonstrated that humans are causing global warming? If the answer is "no", why is the number thrown around always something like "98% of climate scientists" believe in anthropogenic global warming?

It's a good question.

But, the number 98% is misleading. It is really only 98ish% of the ones who have an expressed opinion. While they all pretty much agree the planet is getting warmer, it's much fewer who claim there's sufficient proof to conclude it's being caused by humans.

[wufwugy]

It's a good question.

But, the number 98% is misleading. It is really only 98ish% of the ones who have an expressed opinion. While they all pretty much agree the planet is getting warmer, it's much fewer who claim there's sufficient proof to conclude it's being caused by humans.

Do they all agree that the planet is warming at a faster pace coinciding with human activity? If the opening graph in the OP video is accurate, what statistical methods do they use to justify that?

[Poopadoop]

Do they all agree that the planet is warming at a faster pace coinciding with human activity? If the opening graph in the OP video is accurate, what statistical methods do they use to justify that?

Don't know, but it can't be based solely on the numbers in the graph. I'm pretty sure the more serious ones recognized that a long time ago.

One might argue along the following lines: All other things being equal, global temperature is as likely to have gone down as gone up in the last 150 years, or to have just gone on some random walk. All manner of possibilities are equally likely a priori.

However, the fact that temperature is rising steeply, and that this correlates with the development of industry and the burning of fossil fuels/deforestation, etc., etc., could be seen as suggestive of human-caused warming. It would not be conclusive proof but it would point in that direction.

An analogy would be if a coin came up heads X number of times in a row. It's not that this can't occur by chance, and hasn't occurred by chance in the past, but it's suspicious if this time it just happened to start at the same time as you let Greenhouse Gary do the flipping. With this information alone you can't prove Greenhouse Gary is rigging the global temperature coin (correlation doesn't prove causation) but you'd probably be wise to look into it further.