What proportion of the current global warming trend do you think is caused by humans?

Question

Looking for personal opinions here as opposed to what's in the various scientific reports.

Answer 1

The first question to answer is this:
What percentage of the increase in CO2 levels in the last 130 years can be attributed to humans burning oil, coal, and natural gas. The increase from 1880 to 2007 is 100 ppm or 282 ppm to 382 ppm? Let's assume that 80% of that increase is due to this burning and the rest is due to other factors such as deforestation.

The second question is:
Does the blanket effect of this increase of about 80 ppm correspond the actual rise in world temperatures?

I would like to see an actual experiment that would measure the blanket effect or greenhouse effect of 80 ppm of CO2.

If CO2 is a "greenhouse gas," then let's build a CO2 greenhouse and measure what these different concentration of CO2 actually do in a lab environment. We can construct an actual greenhouse with thermo-pane glass panels and fill the space between the glasses with controlled air with different levels of CO2.

To me, this seems like a simple experiment. My prediction is that 100 ppm of CO2 will produce no measurable difference in the level of retained heat inside the greenhouse.

My guess is that laboratory experimentation will show that 100 ppm of CO2 is not responsible for the measured increase in worldwide temperature.

Answer 2

Well the AR4 says that man is very likely (90%) to be responsible for more than half of the warming trend (NOT to be confused with the oft-misquoted 90% of warming).

There is certainly the possibility, but I don't know if I agree with the probability of that scenario.

There is even the REMOTE possibility that we are responsible for more cooling (sulfate aerosols) than warming, hence a NEGATIVE percentage.

But I don't have the information, obviously, to make a valid hypothesis. I also believe that the scientific community as a whole has not considered enough of the possibilities to diminish and/or eliminate many of the critical ones in order to arrive at their current position(s).

Personally, I'm intrigued by the ocean conveyor. If a dynamic system such as ENSO can have such a huge effect on weather - and even climate to an extent - then it's not hard to imagine the potential forcings of a global system that holds more energy than the atmosphere MANY times over.

Answer 3

I think at least 90%. It is hard to make a personal opinion without backing it up with some sort of reference. The trends over millions of years show that the carbon emission levels have never been this high. It only started to increase once human population increased. I think it is a pretty big coinsidence. The only other thing that could possibly be happening is that we are getting closer to the sun or the sun is getting hotter. I think science would be all over that.

Answer 4

Interesting question. Personally, I think the earth has been in a natural warming trend for several thousand years, but it's very gradual. I don't believe you can give a percentage (despite what the scientists say. A better assessment would be to indicate how far ahead man's influence has impacted the global warming timeline. My guess is man has moved the trend ahead at least 1000-2000 years. In other words, man's use of fossil fuels has done in 120 years what nature would have taken maybe 2000 years.

Answer 5

One good way to find out. Stop all jet airplane traffic for 2 years. The hundreds of thousands of tons of jet fuel being burned above 30,000 ft which produces 3.6 tons of CO2 / ton of kerosene burned would be stopped. Then we could measure the CO2 levels rise or fall. The CO2 rise (if true) correlates best with the increase in jet traffic over the last 50 years. After all CO2 is absorbed instantly by growing plants and by the ocean waters. The sink for CO2 is limitless in the oceans. But it has to come in contact with the waters. Fuels burned on the surface do just that. Even in the winter. Fuels burned in the upper atmosphere take time to drop down to the ocean sink.

Answer 6

Attribution remains sketchy at best. I see nine models used in the most recent IPCC report. 7 of which are considered to be at the level of low scientific understanding.

Thus, any attribution based on these particular models is likely incorrect. I have read papers that have attribution ranges from less than 0.01% up to nearly 100%. Five orders of magnitude between high and low estimates tells me that no one really knows at this point. I sure as hell don't.

Answer 7

Very little, possibly none. The geological record shows that CO2 does not drive climate, in fact climate drives CO2. 450 million years ago the CO2 levels were 15 times higher than they are now and the Earth was in the middle of a major ice age.The CO2 levels remained higher than they are now through the entire span of the ice age and the next warming period. More recently, the ice cores tell us that CO2 lags temperature by about 800 years, due to the fact that as the temperatures warm, biomass increases and as biomass dies it decays and releases CO2. Water vapor is approximately 98% of the green house gas effect and the water cycle is controlled by natural celestial cycles.

Answer 8

I would have to say at the most 10%, and that would be on a good day, I'm just not buying the idea that humans are the main cause of global warming

Answer 9

>>>could desire to anthropogenic acidification of the sea relatively be a bigger venture <<< the sea is under no circumstances "acidic". The PH is approximately 8.2 the sea is in an alkaline state. bear in techniques, merely 4 areas of CO2 exist for each 10,000 areas of ecosystem, and below a style of has been further by utilising guy. maximum scientists have faith this is nearer to a million/2. the sea has been changing CO2 with the ambience for billions of years. The cycle looks like this... lots of the CO2 interior the sea finally unites with H20 to form carbonic acid.. H2CO3. this is the comparable acid this is on your softdrinks.. burb! That carbonic acid finally unearths between the numerous trillions of single Ca ions interior the "salty as in Ca-Cl2" ocean. They bond like rabbits interior the warmth, to make CaCO3 - extra often than not interior the form of coral, yet CO2 additionally bonds with distinctive different minerals to form many different C based compounds. That coral finally dies, compresses and morphs into limestone. as long as there is rain, there'll be adequate mineral ions obtainable for this to ensue. as a results of fact the trillions of gallons of sparkling water falling on land makes it thank you to the sea, it leaches minerals from the soil. as a result, as long as there is rain, there is, and consistently would be lots extra Ca and different minerals obtainable to bind up the wee little bit of CO2 this is being further to the sea each and every three hundred and sixty 5 days. merely for a 2nd evaluate how many billions of numerous minerals are being carried to the sea each and every three hundred and sixty 5 days by utilising the Amazon, Congo, or Mississippi. The concept of "ocean acidification" is the nuttiest of all claims being made by utilising international hysterics. it may be fantastic if a number of those international reactionaries could spend some hours appearing some effortless study. This ain't rocket technological know-how, even with the undeniable fact that it does require extra attempt than does making a peanut butter sandwich.

Answer 10

Well my opinions are based on scientific reports, so this probably isn't want you're looking for, but 80-90% over the past 40 years or so.

Of course, I'd be happy to back that up with a few sources too ;-)