GW skeptics - time to fess up?

Question

Anthropogenic (man-made) GW skeptics can't explain why atmospheric CO2 and global temperature are increasing at the same rate over the past 5 decades.

http://answers.yahoo.com/question/index;_ylt=AjY4Q.RQ.wh1LBn_S.aTY34Fxgt.?qid=20070607125341AAwrVTY

If humans aren't the primary cause of the current global warming, then what is? The sun can't account for it:

"the increase of solar activity could have, on average, contributed approximately 75% of the 1900–1950 global warming but only 25–35% of the 1980–2000 global warming."

http://www.fel.duke.edu/~scafetta/pdf/2005GL025539.pdf

It's not volcanoes - they cause global cooling. It's not water vapor - its concentration is dependent on global temperature

http://www.agu.org/sci_soc/mockler.html

If you can't explain why currently atmospheric CO2 and global temperature are increasing at nearly the same time and rate, and you can't explain what else would cause the GW, when will you admit that it's primarily caused by us?

Mike - according to the study linked above, solar activity may have contributed 30% of global warming. Therefore my guess would be that humans are responsible for roughly 70% of the current warming, which appears reasonable based on this climate model plot:

http://en.wikipedia.org/wiki/Image:Climate_Change_Attribution.png

3DM - can't dispute the data so you personally attack the opposition. Classic tactic for those in a weak position.

Answer 1

1. Land use can account for 0.3 degrees of warming in recent years.

As found in the following quote:

"Our review suggests that the dissenting view offered by the skeptics or opponents of global warming appears substantially more credible than the supporting view put forth by the proponents of global warming. Further, the projections of future climate change over the next fifty to one hundred years is based on insufficiently verified climate models and are therefore not considered reliable at this point in time.

The warming of about 0.3 _C in recent years has prompted suggestions about anthropogenic influence on the earth’s climate due to increasing human activity worldwide. However, a close examination of the earth’s temperature change suggests that the recent warming may be primarily due to urbanization and land-use change impact and not due to increased levels of CO2 and other greenhouse gases"

2. Humans cause nearly none of the warming as quoted here:

"The current global warming is most likely a combined effect of increased solar and tectonic activities and cannot be attributed to the increased anthropogenic impact on the atmosphere. Humans may be responsible for less than 0.01_C (of approximately 0.56_C (1_F) total average atmospheric heating during the last century."

3. Yes, I have the same paper that talks about the sun, as quoted here:

"We estimate that the sun contributed as much as 45–50% of the 1900–2000 global warming, and 25–35% of the 1980–2000 global warming. These results, while confirming that anthropogenic-added climate forcing might have progressively played a dominant role in climate change during the last century, also suggest that the solar impact on climate change during the same period is significantly stronger than what some theoretical models have predicted."

4. Solar Irradiance may be a cause, as quoted here:

"The main cause of climate change during the last millennia is the corresponding cyclic variation of the 80- and 200-year component of irradiance correlated with activity. That is why, the contemporary is not anomalous but is ordinary secular global warming."

5. If CO2 is the culprit, temps should be higher according to this quote:

"The present concentration of CO2 in the atmosphere is about 380, e.g. 100 ppmv higher than it was during any previous interglacial during the last 400, 000 years (3). If climate was responding sensitively to changes in the concentration of CO2, global temperature ought to be considerably higher than it was during previous interglacials. However, the present interglacial has been about 2°C cooler than the previous one, and the climate is now, in spite of the recent warming, cooler than it was at the beginning of this interglacial."

5. CO2 forcing is inconsistent with the multidecadal warming and cooling signals in the Arctic:

"Figure 1 shows the two plausible co-factors of Arctic SAT’s recurring variability and persistent change examined in this paper — the correlation of the annual-mean Arcticwide SAT with TSI and with atmospheric CO2. Figure 1 suggests that the hypothesis of a CO2-dominated warming of the Arctic is not likely consistent with the large decadaland- multidecadal warming and cooling signals contained in the Arctic-wide SAT record. (1) Solar forcing explains well over 75% of the variance for the decadally-smoothed Arctic annual-mean or spring SATs, and (2) Time-frequency characteristics for the annual mean or seasonally-averaged Arctic SATs are consistent with similar wavelet structures derived for the TSI forcing. In contrast, a CO2-dominated forcing of Arctic SATs is inconsistent with both the large multidecadal warming and cooling signals and the similar amplitude of warming trends between cold (winter) and relatively warmer (spring and autumn) seasons found in the Arctic-wide SAT records."

As you can tell, the science is all over the map.

Science is not yet able to attribute a percentage effect to any of the potential drivers of climate change. None of these drivers are exclusive of the others either, they may all be acting in concert to create the climate change that we are seeing.


I have presented a couple of alternative theories to mand made CO2 as the driver of climate change (land use effects, solar and tectonic effects). I have also provided papers that make the case that CO2 is not the driver due to inconsistencies with arctic data.

It seems that I could ask you when you will admit that we just don't know what causes climate change. That seems pointless, though, as there is much more science to be done.

Answer 2

Dana, I wouldn't let anyone know that I have a Master's level science degree. Nor would I mention what school. It reflects poorly on both of you.

Nobody has proven that CO2 is causing global warming. Even one of AGW's chief proponents, James Hansen acknowledges that CO2 is not the primary forcing at this time. So, it is not required for anyone to explain why CO2 and temp are increasing together in the recent past: NO ONE has proven that they DON'T increase more or less simultaneously. It is not the skeptics' job to disprove the unproven (null hypothesis).

Your question asking on Yahoo answers is a microcosmic representation of the in-depth scientific analysis taking place in the AGW community. You ask a question, expecting a certain answer, you immediately discount any point of view which doesn't match your answer, then close your question to new answers once you obtain the desired results.

Shameful, actually.

Answer 3

While to some extent, industrialization has been a factor in the increase of greenhouse gases, it isn't the only reason for Global Warming. Scientists are finding new patterns in nature almost daily. Things we have taken for granted for centuries are being found not entirely accurate.

Quite frankly, 50 years is not long enough to say that there is a problem with the environment. Yes, we can stop polluting our resources so that our life is healthier, but that doesn't mean that we have created global warming. There are actually more forested areas in North America now than when it was first explored by Europeans. While clear cutting of the rainforests in Central and South America is destroying habitats and should be stopped, I don't see the link to global warming.

We should all try to live lightly on the Earth, and stop trying to encite a panic.

Answer 4

Sorry Dana, I answered it and your theories of increased volcanic activity and human aerosol emissions blocking sunlight and creating a degree of global dimming, which led to a short-term global cooling are nonsense IMO. You are claiming that there is less aerosol and volcanic emmissions in the 1980s 1990s and 2000s. St. Helens and Pinatuba were in the 80s and 90s. I would like some evidence for your assertion that aerosols are less now also and how that relates to our warming. Primary causes of warming are the Milankovitch cycles. Take a good hard look where we sit on that cycle. Then look at what trend we are on. If you can't read the chart, the trend is up.

http://en.wikipedia.org/wiki/Milankovitch_cycles

Answer 5

I would admit that it is *partially* caused by us, but I think in our arrogance, we give ourselves more credit for our impact on nature than we deserve.

Until we find a "smoking" gun (pun intended) we really won't know for sure, and I expect that there will always be differences of opinion. There is evidence supporting man-made global warming, but there is also strong, compelling evidence against it. Particuarly, an article from National Geographic suggests that Mars is warming at the same rate as Earth!!! Go figure!

I really can't understand why we don't suspect something cyclic. 10,000 years ago there was a global warming, and so we said bye-bye to the ice age. Did we cause that too?
With just a few thousand years of recorded weather history, how can we know what happens over a period of a million years, or maybe even a billion.

Now, don't get me wrong! We should do everything we can to minimize our impact on the environment. We should also strongly persue renewable sources of energy, so we can let everyone in the Middle East just kill each other, and not us too. But, to make it the paramount political platform around which everything else is simply tangential is wrong, I think. There are many political irons in the fire that need to be dealt with, and thinking only about global warming is too short-sighted.

Just my two cents worth.

BTW, I find the rebuttal in that NG article below to be sooo hypocritical and transparent: "His views are completely at odds with the mainstream scientific opinion." Where have I heard that before... Oh yeah:

"The Earth is not flat, it's round!"
"That view is completely at odds with the mainstream."

I guess we'll just need to wait and see. If this guy is correct, then we only need to wait out the 15 to 20 years he says it will take to start noticing the cooling to prove him correct.

Answer 6

I am a "skeptic". My formal scientific training is limited to the general education courses needed to meet the core requirements of the BS in Accounting I never completed. I worked two years as a support tech in the wet lab of a company that analyzes smokestack emission samples for EPA compliance. I'm currently a stay-at-home dad with way too much time on my hands (wife's a mass spec chemist with a BS in Physics). When I'm not playing on here, I'm tinkering with my latest "invention" or reading anything and everything spanning any and all disciplines, scientific or otherwise. Edit: And derek w proves why Sociology isn't a science.

Answer 7

Ditto on the answer by one_n1ce_guy. He is right. There IS GW happening, but the question is now, why? He suggested very good examples and data we've seen recently (I love the Mars warming portion of that since it is such a control compared to the Earth). The Earth has gone through this many times before, it is a spike in the natural cycle. Look at the cycles on a timeline over the past 100,000 years. It is all within "normal" cycles still, but if you look at a graph over the past century, it looks like the temperatures are rising dramatically.
There is no question that GW is happening, but is it man-made? Most likely not enough to worry about (I saw an unbiased article that stated we may be having an effect of about 3%, I'll look for that info). HOWEVER, it is still good for us to reduce our "carbon footprint" since doing that is just a good idea for the environment and people in general. I ride my bike more, use less electricity by turning off lights and replacing them with high-efficiency bulbs, we insulate the house and water heater, and keep the A/C at 78 and the heater at 66. Am I worried that people will kill the Earth with their emissions and pollutants? No. There is no repeatable and peer reviewed evidence to support that, but it is in the best interest for us all to try and conserve resources and reduce pollution.

Answer 8

Actually Dana 1981, I would be very interested to know what your estimate is of the amount of Global Warming caused by human activity and the amount of Global Warming caused by natural processes.

Is your estimate that 100% of current Global Warming is caused by human activity, or 90% caused by human activity and 10% caused by natural processes or do you have some other estimate,

and how do you arrive at your estimate.

Answer 9

Lol, still at it? you can't prove anything but you still babel on about how "skeptics" need to prove the negative. Prove what else is doing it, wait hold on, is this the same person that posted a question lamenting that the "skeptics" all of a sudden wants proof? Now we have a question in which you want us to prove to you that something else is warming up your preciously fragile earth? Global warming is a farce. We got temps going up, we got temps going down, over the long a haul. The globe is not warming, go back to your books. Live life, be happy. No I am serious get a life, live it, love it. Your wackiness is starting to scare me.

Answer 10

Have you ever taken a class on statistics?

Do you not see that we don't have enough long term data to draw a correct conclusion?

Do you understand correlation is not the same as causation?

I could easily argue the increase in temperature caused the CO2 from those types of graphs as you could argue the opposite.

Can you point me in the direction of a study that shows that the increase in carbon dioxide from man-made sources is significant to a 95% confidence interval using data from the last 10 or so climate cycles?

Do you know of a study that shows the total estimated amount of carbon that man has put into the atmosphere, that estimates the amount from the amount of coal and other combustion processes that we have carried out and then compared that amount to the carbon that is from other sources?

Answer 11

Don't you see? This same warming may have happened hundreds of times before. Maybe this warming has happened a thousand years ago. Over time it may be followed by a cooling, which in turn may be followed by yet another warming and so on. There is nothing to panic about. The world as we know it will not end. We are not all going to perish as a result of this warming trend. Just about everything we understand to date has a pattern. This wave pattern occurs often in nature, including ocean waves, sound waves, and light waves.All of these can be graphed or illustrated with a sine wave, and as a result can then be monitored and analyzed. In the case of global temperature we just don't have enough accurate data yet to ''plot'' a pattern which would help us predict coming changes. Don't forget, the only accurate recorded data we have dates back only about 100 years, everything else is just theories and guesswork. So you see, it's just a natural cycle. In fact, if we could and did change global warming we may in fact do greater damage to the Earth's future as this current warming may be vital to it's ecosystem!