Co2 Does Not Cause Global Warming

• The carbon dioxide greenhouse effect provides a scientifically valid mechanism. CO2 produces a warming effect not by soaking up the radiation in its immediate vicinity, like a sponge, but by raising the effective radiating level of the atmosphere to a colder layer.

• The atmosphere doesn’t act as a single unit, but is made up of hundred of different layers. Some of the energy radiated from Earth is stopped in each of these layers. The energy is then re-radiated in a random direction, but on average the energy is moving either “up” or “down.” The atmosphere gets thinner as altitude increases, so eventually the radiation will reach a layer high enough and thin enough to escape to space.

• If you increase the concentrations of a greenhouse gas in the atmosphere, the thin upper layers will become more opaque and thus absorb more of the IR; therefore the place where the majority of the energy finally escapes moves to a higher level. These higher levels are much colder (until you reach the stratosphere, but as most infrared photons escaping to space are emitted by the troposphere, this can be ignored), and so they do not radiate heat very well. Thus the rate that radiation escapes to space is lower, and the planet will take in more than it radiates. As the higher levels emit some of the excess downwards, the lower levels will warm all the way down to the surface.

• The imbalance will remain until the higher levels get hot enough to radiate as much energy back out as the planet is receiving.

• 19th century physicist John Tyndall described the effect neatly like so:

“As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown as a barrier across the terrestrial rays, produces a local heightening of the temperature at Earth’s surface.”

• The Earth’s climate is a complex and dynamic system that is subject to a multitude of different forcings on many different timescales. The fact that the climate can change and has changed independently of carbon dioxide does not mean that carbon dioxide cannot change the climate. It simply means that some other force, be it an increase in solar output, a change in the planet’s albedo, etc., has overwhelmed the forcing signal from carbon dioxide.

• In 1991, for example, after the eruption of Mount Pinatubo, there was a sharp drop in global temperature following the massive outpouring of ash from the volcano. This sudden increase in air born particulate matter briefly overwhelmed many other forcing factors and drove the temperature down by several degrees until the ash settled out of the atmosphere. This is just one of many examples of a short term forcing managing to overwhelm a longer term forcing, such as an enhanced greenhouse effect.

– Global temperatures have often changed in parallel with CO2 increases over the Earth’s history. We know this from the fossil record and measures of trapped gas in the ice caps. We know that CO2 is a greenhouse gas. So, even if the CO2 does not come exclusively from human emissions (i.e. not anthropogenic) we are currently experiencing an increase in it and this is linked to climate change. At least SOME of the increase can be attributed to human activities either directly or indirectly (Burning of fossil fuels is direct. Deforestation is less direct. Etc.).

There are probably other factors which are contributing to the warming effect, both natural and man-made. However, calculations also show that the rise in temperature can be easily explained by the increased levels of CO2 in the atmosphere. Until another compelling explanation is put forward, this would seem to tbe the most likely cause.

Also, just because something else could be causing global warming doesn’t mean that it is.

Also, change in land use and ubranization both cause changes in CO2 content in our atmostphere.If we cut down more trees, lesser trees will be available to absorb CO2. And the change in CO2 content causes global warming

• All of the energy flowing from Earth to space is necessarily in the form of electromagnetic radiation. Earth is floating in a vacuum, making it physically impossible for it to lose energy through conduction or convection. So while much of the energy moving across the planet’s surface is not in the form of radiation, it is the only form of energy important in determining the planet’s temperature–the planet’s temperature being determined by the ratio of the flux of outgoing terrestrial radiation to the flux of incoming solar radiation.

• Also, carbon dioxide is an effective absorber in the infrared spectrum. Due to its temperature, Earth radiates energy primarily in the infrared spectrum. So while carbon dioxide may fill a small absorptive window, it fills a very important one.

Oceans do absorb atmospheric CO2. And under normal conditions the oceans and the biosphere will generally keep the amount of CO2 in the atmosphere constant. However, human activities are producing CO2 at a much higher rate than the planet’s oceans and biosphere are able to absorb it. This imbalance is responsible for virtually the whole of the 20th century rise in CO2.

Also, estimating pH changes need not involve any stabbing in the dark thanks to fossil records and certain species being restricted by pH (e.g. shelled molluscs) due to their physiological requirements. And 0.15 pH units may not sound like much but pH is measured along a logarithmic scale.

• Surface monitoring stations are not the only evidence that the planet is warming. satellite data, radiosondes, borehole analysis, glacial melt observations, sea ice melt, sea level rise, proxy reconstructions, and permafrost melt all conclusively show that the planet has undergone a pronounced and rapid warming over the past century and a half. So even if the entire surface temperature record were contaminated beyond use, there would still be no doubt whatsoever that the planet is warming.

• Aside from this, it has been demonstrated in several independent studies (Peterson, 2003) that the urban heat island effect does not significantly affect the surface temperature record. That is, the 20th century warming trend is not simply an artefact of urban development.

• It is also important to note that the warming trend is not an output of a computer model, but a conclusion based upon observing real-world evidence such as that listed above.

Among other factors which may be responsible for climate change, human action is generally regarded a strong contribution – and one which looks set to increase, particularly in light of the swift industrialization of certain large nations, such as China. There may not be time to wait.

“At least 40 per cent of the world’s economy and 80 per cent of the needs of the poor are derived from biological resources.” — The Convention About Life on Earth (UN Convention on Biodiversity)
Climate change interferes with ecosystem functioning and resources provided by the ‘natural’ environment. For example, rainfall in the tropics is largely created by the rainforests themselves, the potential for pharmaceuticals being discovered, timber resources etc. These have been valued at US $33 trillion. This is compared to a global GNP of $18 trillion.

Anthropogenic effects on climate change are accepted by more than 99% of climate scientists. The longest, high resolution datasets in the world are land and sea surface temperature, collected since the 1860s, the errors of which have now been statistically corrected (Folland and Parker, 1995). Since the advent of climate modeling since the early 1990s, technology has improved so rapidly that scientists are now able to isolate the different forcings of climate change, and have shown unequivocally that natural variability, sun spots and volcanic activity are not able to explain the rise in global temperature, and that anthropogenic emissions of CO2 (which have been monitored in Hawaii since 1957) is the only plausible explanation for the additional, catastrophic rise in temperature.

• Using sound and well understood physical principals, scientists are able to construct accurate and reliable models of Earth’s climate which they can then use to “hindcast” past climate changes. They have discovered that when only natural factors are included, the models do not accurately reflect the 20th century climate change. It is only when both natural and anthropogenic factors (such as CO2) are considered that the models present realistic results.

• Scientists have also been unable to discover any natural forcing-such as changes in solar output-active during the past century sufficient to have produced the bulk of the 20th century warming trend.

All of the points in the ‘yes’ camp are bunkum and easily dismissed.

1. There is no scientifically valid mechanism for CO2 causing global warming.

Actually, there is, it was first discovered by Svante Arrhenius well over 100 years ago and has been built on by subsequent decades of research, it underpins our understanding of the so-called ‘greenhouse effect’ [1]. CO2 and other greenhouse gasses are virtually transparent to incoming shortwave radiation, which hits the Earth causing it to warm and emit a percentage of that energy as longwave infra red radiation. The greenhouse gasses are not transparent to IR so as it interacts with GHG molecules the IR is scattered, with a percentage being bounced back to Earth which causes an energy imbalance, more energy is going into the system than is leaving it. As greenhouse gas concentrations in the atmosphere increase so does this energy imbalance. All of this is quantifiable, we can measure incoming and outgoing energy from space and from the surface and construct global accounting models that are very, very accurate, and is backed by decades of research [2]

[1] http://www.aip.org/history/climate/co2.htm
[2] http://www.skepticalscience.com/empirical-evidence-for-co2-enhanced-greenhouse-effect.htm

2. Global temperatures have always been changing despite Co2 increases

True but inconsequential as to the question of whether the current warming is being caused by CO2. There are several factors, commonly referred to as ‘forcings’, that will cause the climate to change – insolation (the sun), albedo, greenhouse gasses, and feedbacks – for the climate to change one of these has to change [1] The ice ages, for instance, are caused by the changes in solar energy reaching the planet due to a combination of its elliptical orbit and precessional wobble [2], the so-called Medieval warm Period was caused largely by an increase in solar activity [3], the so-called Little Ice Age was caused by a combination of reduced solar activity and increased albedo from heightened volcanic activity [4]. But just because there are other factors that can influence the climate doesn’t in any way change the fact that an increase in greenhouse gasses will influence the climate as well. Indeed, it is within these past climate shifts that we can see the clear evidence of exactly how the planet responds to changes in CO2.. For instance, it is known that the orbital changes that bring the Earth in and out of ice ages aren’t actually strong enough to warm the planet to the degree that it does during an interglacial, the only way you can explain it is if the thawing oceans release a significant quantity of CO2 into the atmosphere which amplifies the change in insolation and warms the planet by a significant fraction [5]

[1] http://en.wikipedia.org/wiki/Climate_forcings
[2] http://en.wikipedia.org/wiki/Milankovitch_cycle
[3] http://en.wikipedia.org/wiki/Solar_variation
[4] http://en.wikipedia.org/wiki/Little_ice_age#Causes
[5] http://www.realclimate.org/index.php/archives/2004/12/co2-in-ice-cores/
[4]
[5]

3. The ‘Global warming’ phenomenon could be caused by other things

It *could* be, but then again the Universe *could* be made of pixie dust too. While there are still one or two competing theories out there – cosmic rays and solar cycles are about the only examples that still have some academic backing – nobody has come close to developing any kind of satisfactory alternative model, most of the ideas have been tried and tested and found to be flawed. [1] Whereas the standard ‘greenhouse’ model is based on 150 years of research and observation, it’s physics are very well understood, in fact to overturn the greenhouse model you would have to rewrite physics because everything we know about the heat trapping properties of CO2 supports the greenhouse model [2]. That’s why 98% of researchers in the relevant fields agree with the tenets of AGW as outlined by the IPCC [3].

[1] http://www.skepticalscience.com/Svensmark-Friis-Christensen-rebut-Lockwood-solar-paper.html
[2] http://www.aip.org/history/climate/co2.htm
[3] http://www.pnas.org/content/early/2010/06/04/1003187107.abstract

4. Co2 does not hold in heat!

It doesn’t need to and nobody has ever claimed that it does. As explained above, the so-called greenhouse effect isn’t caused by CO2 storing heat, rather the way in which in absorbs and remits IR radiation, which traps thermal heat in the system, most of which is stored in the oceans and not in the atmosphere. [1]

[1] http://www.skepticalscience.com/How-we-know-global-warming-is-happening-Part-2.html

5. Oceans regulate the amount of CO2 in the air through absorption equilibrium

True but misleading. Oceans also lose their capacity to absorb as the turn more acid from increased Co2 absorption. This is global warming sister crisis, even if CO2 didn’t cause the globe to warm we would still suffer an ecological catastrophe as the oceans acidify, as is already being observed, and lose their capacity to maintain life.[1] Add to this the fact that at the same time as dramatically increasing CO2 output we have also significantly depleted the planets biomass, further reducing the natural carbon cycle to absorb the excess being produced by human activity (currently about 60% of our emissions are being naturally absorbed back into the carbon cycle [2]). But at any rate, the whole argument is an inconsequential distraction from the reality of the situation: we know for a fact, quantifiably so, that CO2 concentrations have increased by about 37% since pre-industrial times, which is certainly higher than at any point in at least 800,000 and almost certainly a lot longer than that [3], and we can identify that the increase is a result of human activity through chemical fingerprinting of the gasses [4]. It is blindingly obvious that CO2 levels are rising faster than the planets ability to absorb them.

[1] http://en.wikipedia.org/wiki/Ocean_acidification
[2] http://www.nasa.gov/mission_pages/oco/mission/index.html
[3] http://www.csiro.au/news/Climate-Change-Palaeoclimatic-Context–ci_pageNo-2.html#2
[4] http://www.skepticalscience.com/Human-fingerprint-on-atmospheric-CO2.html


6. Measurements are inaccurate

The really funny thing about this is that when NOAA went back over their data and applied Watt’s methodology they did indeed find an inaccuracy in the record, they found a slight cooling bias, meaning that they subsequently had to readjust their surface temperature record to show that it has been slightly warmer than previously believed. The very graciously thanked Watts for alerting them to this problem, in a moment that must have been a considerable embarrassment for the TV weatherman and his legions of amateur temperature-station photographers! [1]

[1] http://www1.ncdc.noaa.gov/pub/data/ushcn/v2/monthly/menne-etal2010.pdf