Just saw this information. How do you explain it?

Question

I was recently watching a discussion between two individuals. One believed that global warming was real and was a response to manmade introduction of green house gases such as carbon dioxide into our environment. The other believed that we are seeing a normal climate shift that the earth has seen many many times before and that most climate shifts throughout the earths history have characteristically been quite rapid rather than occurring over hundreds and hundreds of years.

The second individual stated this fact which I had never heard before. By studying information related to all the previous prehistoric climate shifts it is apparent that temperatures increased BEFORE we see an increase in carbon dioxide levels. He believes that the increases in carbon dioxide are not CAUSATIVE to climate changes but rather a response to climate changes that normally occur on our earth.

Can anyone explain the fact that carbon dioxide increased AFTER temperatures increased.

That is exactly my point. No one was alive but we have geological record of our previous climate changes which show carbon dioxide increasing AFTER temperature went up. So again can anyone explain this?

Answer 1

The scientist who made the chart that Al Gore, in his Oscar winning movie, used to drive his 'CO2/Global Warming connection' home, is on record stating that Gore was completely wrong, and that the chart, when accurately explained by someone who knows the time stamps of the data entered in it would have been telling the same audience that CO2 levels follow temperature levels, up and down, by about 800 years.

The difference is, his comments can only be found on a documentary which will never be seen in a major motion picture studio theater. Never mind that it will never win an award for documentaries, he is the real scientist who did the research and created the chart Gore used to push his Global Warming Disaster Doctrine, and his interpretation of his own chart will never be heard by most of the people who saw Gore's movie.

That is the problem with how the global warming debate has been conducted by the news media. Only one side of the debate is covered 'on camera'. The rest of the research is forced underground by an environmentalist religion with similar authority over what is taught as fact as the Catholic clergy who made sure everyone was on board with the 'Earth is the Center of the Universe' doctrine of that time.

Answer 2

As the article below explains, the time lag is not in atmospheric CO2 levels. The time lag is due to the time it takes for atmospheric gasses to become trapped and compressed in ice. In other words, the time lag occurs because the ice is older then the air trapped inside it. So, you take an ice core and calculate the temperature based on the thickness/condition of the ice, and then you measure the carbon in the air bubles trapped in the same piece of ice. But you have an air sample that is much younger then the ice around it, so there is a disparity. Scientists know about it, but don't know how to properly account for it in the timeline. So the historical CO2 levels might be off by a couple of hundred years when compared with temperature data. But, you're talking about a disparity of as little as 200 years, which is completely insignificant geologically speaking. In practice, scientists posit that temperature and CO2 level go up at the same time, which seems to be what is happening in this article:
http://www.cnn.com/2007/TECH/science/06/06/greenland.warming.reut/index.html
Uninformed skeptics latch on to obvious inconsistencies like this and tout it as scientific proof that global warming is a farce. The only thing that it scientifically prooves is that you have to be really smart to be good at analyzing scientific data. You can't just be some schmuck off the street, look at a graph for 20 seconds and poke a credible hole in a theory that has gained the kind of consensus that climate change has.

Answer 3

Bob and Trevor explained it quite well.

Carbon dioxide can increase as a result of global warming (if something else initiated the warming) and then amplify it.

Carbon dioxide can also initiate global warming if its atmospheric concentration increases at a time when global warming isn't happening.

People often cite the "800 year lag" in historical temperature vs. atmospheric CO2 concentration data. Global temperatures increased, and then several centuries later CO2 levels increased and amplified the global warming. This is because something else initiated the global warming.

Global warming skeptics then conclude that because historically CO2 lags behind temperature, that CO2 increases cannot cause global warming. This is a logical fallacy, because of course CO2 can cause global warming, since it's a greenhouse gas. If all else remains constant and atmospheric CO2 levels increase dramatically, you would expect to see global warming as a consequence. And that's exactly what you can see in the following graphs.

As atmospheric carbon dioxide concentrations increased regularly from 1960 to present day:

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

Average global temperature increased very similarly:

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

There are certainly other causes besides greenhouse gases, but to model the current warming, greenhouse gases dominate other factors:

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

So to answer your question, the explanation is that historically humans weren't emitting tons of CO2, therefore other climate factors dominated when global warming occurred, and CO2 eventually increased as a feedback to global warming and amplified it. In the current situation, CO2 concentrations have increased so much by human fossil fuel burning that it dominates other factors, which is why you can see temperature increasing along with CO2, with temperature lagging just slightly behind.

Answer 4

The overall rise of about plus 0.5 ºC during the 20th century is often cited in support of ''global warming'' (38). Since, however, 82% of the CO2 rise during the 20th century occurred after the rise in temperature (see figures 1 and 12), the CO2 increase cannot have caused the temperature increase. The 19th century rise was only 13 ppm (2).

"Environmental Effects of Increased Atmospheric Carbon Dioxide" ARTHUR B. ROBINSON, SALLIE L. BALIUNAS, WILLIE SOON, AND ZACHARY W. ROBINSON 1998

Answer 5

Here's the explanation.

CO2 has two properties. It causes warming, due to the greenhouse effect. And, it is released by warming, as ocean waters warm. Both properties are well established scientific fact.

In the past natural warmings started for other reasons. Years later, as the warmings progressed CO2 was released from the oceans and rose later.

This time data clearly shows warming and CO2 going up together. Your friends fact is one of the many proofs that this warming is not like the natural warmings of the past, it is actually being caused by us, burning fossil fuels and releasing CO2.

More details here:

http://www.realclimate.org/index.php?p=13

Answer 6

It never ceases to amaze me that people who have never studied global warming and whose knowledge of the subject is confined to a few websites and media reports feel they are qualified to comment on the subject and pass opinions off as fact.

Anyway, the explanation isn't something new, it's been known about since 1896, here's a condensed and simpliied explanation (let me know if you want a detailed one)...

Increased levels of atmospheric greenhouse gases lead to global warming.

AND

Global warming leads to increased levels of atmospheric greenhouse gases.

The two things are inexorably linked through a Feedback Process - it doesn't matter which comes first, the other will follow. It's explained more on Wikipedia - http://en.wikipedia.org/wiki/Global_warming#Feedbacks

In the past of course there was no large scale human induced emissions of greenhouse gases. The climate changed through natural cycles* leading to warming (or cooling) which in turn led to an increase (or decrease) in greenhouse gas levels. These changes happened very slowly, over periods of thousands of years.

Since the Industrial Revolution we have upset the natural balance by introducing many times more greenhouse gases into the atmosphere than nature can handle*. The result is a large accumulation of greenhouse gases in the atmosphere.

One of the physical properties of greenhouse gases is that they trap heat and any increase, even if it's only a small one, will lead to an overall warming effect.*

A good example is to look at what's happened to the Siberian permafrost...

As we release more and more greenhouse gases the temperature starts to rise, as the temperature rises the permafrost begins to melt (one million square kilometres of it in the last 4 years), as the permafrost melts it releases methane trapped in the peat beneath it* (70 billion tons in all), methane is a potent greenhouse gas* and it causes temperatures to rise, this melts more permafrost, more methane is released and so it goes on.


* If you want more info about any of these points you can e-mail me, post another question or look them up, the search terms to look for are Milankovitch Cycles, Solar Variation, Greenhouse Gases, Radiative Forcing, Methanogenis or Biomethanation, Global Warming Potential.

Answer 7

Scientists can look at cores of ice and can somehow tell how much pollution/carbon was in the air. That may help you with the edited part of your question.

Answer 8

I wasn't alive then. That's why it's important to retrieve meteorites and study the burnt crusts of these wayward rocks. They give us information of what was in the atmosphere way back when.

Answer 9

I haven't heard that either. It would have been helpful if the person named the study he took his information from, or to know if he did it himself.