IF man is the cause for Global warming why do CO2 levels rise after the temperature rises?

Question

It's been proven over the past thousands of years that CO2 levels rise after temperatures rise. With that being said how can man be causing global warming if it's all about the CO2 amounts when the temperature started going up before the CO2 levels started to rise?

Answer 1

Or why do temps fall even though co2 levels continue to increase?

Clearly increased co2 is the symptom of warming, not the cause.

The Sun is the source for all heat on this planet. Any small fluctuations of output of the Sun's energy is going to cause major changes in the Earth's climate.

Answer 2

The climate system is far more complex than A causes B. Often it's more like A causes B, which causes more B and also C, and C in turn causes more B but a little less A. And that less of A causes less of B.

In the case of *natural* rises and falls of CO2, the triggers are orbital forcing the and ice-albedo effect. Small changes in earth's orbit cause less (or more) snow to fall in Siberia and Canada during the winter. As less snow falls, the earth reflects less sunlight and absorbs more, causing the planet to warm a little bit. This in turn causes less snow, which causes more warming.

As the planet warms, the oceans warm too, which causes the oceans to release a bit of the CO2 that is dissolved in the water -- because warm water holds less CO2 than cold water. It typically takes many hundreds of years of ice-albedo feedback to get the oceans to warm enough to begin releasing CO2. But once that happens, the CO2 causes more greenhouse effect, causing more warmth, causing more CO2 release: it's a huge positive feedback cycle.

This natural cycle had reached a peak temperature 6000 years ago during the Holocene Maximum, and orbital forcing -- which starts the whole ball rolling -- was beginning to slowly cool the planet, and the oceans had begun to absorb more CO2.

Now we (us humans) have upset the applecart. Burning of fossil fuels began to release vast amounts of CO2 into the air, causing the current warming spell. We're actually lucky that up to this point, the oceans have absorbed roughly half of the CO2 that we have produced. But It is predicted that at current rates, by 2100 the oceans warm enough to stop absorbing CO2 and start emitting back to the air some of that CO2 that we produced in the 20th century.

If we don't have a handle on our CO2 emissions by that time, we're all screwed. The climate will go into a rapid positive-feedback mode, and mass extinction will result.

Answer 3

rising temperatures aid decomposition. Extra decomposition = more CO2.

Meanwhile, the CO2 in today's atmosphere is not from decomposition. It is from man burning carbon that has been long buried, and, it is proven that CO2 traps more heat than nitrogen.

CO2 emissions and capture do not occur at a fixed rate each year: every 10 years or so, there is a major volcanic eruption, and volcanos are quite random in magnitude. Strong ones temporarily cool the earth with sulfuric aerosols, but they also release carbon dioxide. Aerosols rain out in a few years, the carbon stays for hundreds.

Answer 4

This is an excellent question. It turns out this is actually PROOF that global warming is mostly man made. Read on.

Past warmings started for natural reasons (usually the Sun). Then, as ocean waters warmed, they couldn't hold as much CO2 and released some. The process takes hundreds of years, and the lag is clear in the data.

But this time things are clearly very different. The data shows CO2 and temperature are going up together. _There is no lag_. It's because CO2 is the main cause of the current warming. This is one of many reasons scientists know this warming is different, and caused mostly by us.

CO2 acts two ways. It can cause warming and it is also released from oceans by warming.

More here:

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

Answer 5

Won't go into technical details as would take a long time but the important thing to understand is that increasing CO2 and temperatures are part of a feedback mechanism - it makes no difference which comes first as the other will follow.

CO2 (and other greenhouse gases) have a physical property that enables them to retain thermal radiation (heat) within Earth's atmosphere, the higher the atmospheric concentrations of these gases the more heat is retained.

But also.... higher temperatures lead to accelerated release of greenhouse gases from the oceans, biomass etc.

A leads to B leads to A leads to B etc.

Further, if the greenhouse gases didn't have the ability to retain heat then our planet would be so cold that life would never have evolved. It's only because of a super greenhouse effect in the distant past (3.7 billion years ago) that life formed on Earth.

Answer 6

your arguement is unsound although co2 rises with temp. the relation between the two before the rise of mankind was uniform and predictable. the temp increase resulted in a co2 increase at a rate of change that was always within certain values. in the last 50 years the rate of co2 increase was so drastic that temp alone could no longer account for the increase. the existence of a second "confounding variable" is the only way to account for such dramatic differences between the two time periods

Answer 7

Historically there was no source emitting CO2 independently of temperature. Something else initiated global warming (natural cycles, if you like), and then the oceans began to emit CO2 (which is less soluble in warmer water), then the CO2 amplified the global warming.

This proves that CO2 is capable of causing global warming.

Now there is a source of CO2 emissions independent of global temperature - humans burning fossil fuels. That's how our current situation is different from historical warming.

Answer 8

Past performance is no guarantee of future performance. Take a look at the graph in the source and you will see that the CO2 change in the last 200 years is TOTALLY different than any natural change of the last 400,000 years. There is no way that is a natural increase in CO2 due to an unrelated temperature change. The suddenness of the change is unprecedented, and far greater than any past natural change.

Answer 9

global warming is the rise in temperature due to depletion of the ozone layer. the ozone layer is deleting due to activities of the green house gases called green house gas effect. CO2 is a mojor contributor to green house gas.

therefore temperature rise which is due to heat from the sun on the earth becouse of the depletion of ozone layer due to CO2 activity can not be unrelated to CO2 abundance. i hope u see a link.

Man's activity only enhances the production otherwise the abundance of CO2 which is what depletes the ozone layer that is the barrier that reduces the sun's direct heat on the earth's surface

Answer 10

Well, Earth has naturally grown warmer for thousands of years but at like one degree every hundred years which is natural and natural is good, but when fossil fuel burning was introduced, it has gone up more than it is supposed to be which is not good.