Tkman117
Posts: 1353
Joined: 5/21/2012
Status: offline
|
quote:
Finally, you are getting the point. Finally after about 3000 posts.
So now you are making the ASSUMPTION that it is the dominant factor. Great. Show me a theory (anywhere) that proves that.
Hell. Show me a theory *anywhere* that even assigns a relative weighting to the variety of factors. And then lets look at how well that model predicts temperature.
But, in the end, there is NOWHERE that this forcing has been quantized. Because the alarmists know that to quantize it means to subject it to scientific process and either prove it or disprove it.
I essentially quoted you the data which assigns the relative weight to the variety of factors, or did you miss this part:
quote:
Surface Albedo has changed due to activity such as deforestation. This increases the Earth's albedo - the planet's surface is more reflective. Consequently, more sunlight is reflected directly back into space, giving a cooling effect of -0.2 Wm-2.
Ozone affects the climate in two ways. The depletion of stratospheric ozone is estimated to have had a cooling effect of -0.05 Wm-2. Increasing tropospheric ozone has had a warming effect of +0.35 Wm-2.
Solar variations affect climate in various ways. The change in incoming Total Solar Irradiance (TSI) has a direct radiative forcing. There is an indirect effect from UV light which modifies the stratosphere. The radiative forcing from solar variations since pre-industrial times is estimated at +0.12 Wm-2. Note that the radiative forcing from solar variations may be amplified by a possible link between galactic cosmic rays and clouds. However, considering the sun has shown a slight cooling trend over the last 30 years, an amplified forcing from solar variations would mean a greater cooling effect on global temperatures during the modern warming trend over the last 35 years.
Volcanoes send sulfate aerosols into the stratosphere. These reflect sunlight, cooling the earth. A strong volcanic eruption can have a radiative forcing effect of up to -3 Wm-2. However, the effect of volcanic activity is transitory - over several years, the aerosols wash out of the atmosphere and any long term forcing is removed.
Aerosols have two effects on climate. They have a direct cooling effect by reflecting sunlight - this is calculated from observations to be -0.5 Wm-2. They also have an indirect effect by affecting the formation of clouds which in turn affect the Earth's albedo. The trend in cloud cover is one of increasing albedo which means a cooling effect of -0.7 Wm-2.
Stratospheric Water Vapour has increased due to oxidation of methane and had a slight warming effect of +0.07 Wm-2.
Linear Contrails from aviation have a slight warming effect of +0.01 Wm-2.
Nitrous Oxide reached a concentration of 319ppb in 2005. As a greenhouse gas, this contributes warming of +0.16 Wm-2.
Halocarbons (eg - CFC's) were used extensively in refrigeration and other industrial processes before they were found to cause stratospheric ozone depletion. As a greenhouse gas, they cause warming of +0.337 Wm-2.
Methane is actually a more potent greenhouse gas than CO2. Pre-industrial methane levels, determined from ice core measurements, were around 715 parts per billion (ppb). Currently methane rates are at 1774 ppb (eg - 1.774 parts per million). The radiative forcing from methane is +0.48 Wm-2.
CO2 levels have increased from around 280 parts per million (ppm) in pre-industrial times to 384 ppm in 2009. The radiative forcing from CO2 is +1.66 Wm-2. CO2 forcing is also increasing at a rate greater than any decade since 1750.
quote:
Hence my claim for the ever so longest time that AGW isn't science. I do no dispute temperatures, or fresh water flows. But for it to be AGW, you have to prove
a). That CO2 is the dominant driver.
quote:
http://www.skepticalscience.com/empirical-evidence-for-co2-enhanced-greenhouse-effect-advanced.htm
Climate sensitivity
As the name suggests, climate sensitivity is an estimate of how sensitive the climate is to an increase in a radiative forcing. The climate sensitivity value tells us how much the planet will warm or cool in response to a given radiative forcing change. As you might guess, the temperature change is proportional to the change in the amount of energy reaching the Earth's surface (the radiative forcing), and the climate sensitivity is the coefficient of proportionality:
dT = λ*dF
Where 'dT' is the change in the Earth's average surface temperature, 'λ' is the climate sensitivity, usually with units in Kelvin or degrees Celsius per Watts per square meter (°C/[W/m2]), and 'dF' is the radiative forcing.
So now to calculate the change in temperature, we just need to know the climate sensitivity. Studies have given a possible range of values of 2-4.5°C warming for a doubling of CO2 (IPCC 2007). Using these values it's a simple task to put the climate sensitivity into the units we need, using the formulas above:
λ = dT/dF = dT/(5.35 * ln[2])= [2 to 4.5°C]/3.7 = 0.54 to 1.2°C/(W/m2)
Using this range of possible climate sensitivity values, we can plug λ into the formulas above and calculate the expected temperature change. The atmospheric CO2 concentration as of 2010 is about 390 ppmv. This gives us the value for 'C', and for 'Co' we'll use the pre-industrial value of 280 ppmv.
dT = λ*dF = λ * 5.35 * ln(390/280) = 1.8 * λ
Plugging in our possible climate sensitivity values, this gives us an expected surface temperature change of about 1–2.2°C of global warming, with a most likely value of 1.4°C. However, this tells us the equilibrium temperature. In reality it takes a long time to heat up the oceans due to their thermal inertia. For this reason there is currently a planetary energy imbalance, and the surface has only warmed about 0.8°C. In other words, even if we were to immediately stop adding CO2 to the atmosphere, the planet would warm another ~0.6°C until it reached this new equilibrium state (confirmed by Hansen 2005). This is referred to as the 'warming in the pipeline'.
Of course this is just the temperature change we expect to observe from the CO2 radiative forcing. Humans cause numerous other radiative forcings, both positive (e.g. other greenhouse gases) and negative (e.g. sulfate aerosols which block sunlight). Fortunately, the negative and positive forcings are roughly equal and cancel each other out, and the natural forcings over the past half century have also been approximately zero (Meehl 2004), so the radiative forcing from CO2 alone gives us a good estimate as to how much we expect to see the Earth's surface temperature change.
quote:
b). That it is uncapped. (It isn't).
quote:
http://www.skepticalscience.com/saturated-co2-effect-advanced.htm
After the famous Arrhenius paper in 1896, where he did the first calculations of the CO2 greenhouse effect, his theory was dismissed by Angstrom with a simple experiment. He let an infrared beam pass through a tube filled with CO2 and measured the emerging light intensity. Upon reducing CO2 concentration in the tube, only a tiny difference could be found and he concluded that very few CO2 molecules are enough to completely absorb the IR beam. The conclusion was that a CO2 increase could not matter. This was the birth of the first skeptic of the then called "CO2 theory" and of the more recent "CO2 effect is saturated" skeptic argument.
Thirty years later, E. O. Hulburt (Phys. Rev. 38, 1876–1890 (1931)) added convection to the purely radiative equilibrium assumed by Arrhenius. He found that convective equilibrium holds in the lower part of the troposphere up to about 10 Km, while radiative holds equilibrium above. The important consequence is that the details of the absorption in the lower troposphere do not matter since heat "is spread around and transferred upward by convection". In other words, what govern the energy balance of the earth is the radiative balance in the upper troposphere and CO2 concentration there does matter.
Hulburt was very prudent in his conclusions:
"The agreement is no doubt better than is warranted by the accuracy of the data on which the calculations are based. Apparently the uncertainties and omissions have conspired to counteract each other to some extent."
Nevertheless, his work is definitely a milestone in the understanding of our atmosphere.
Hulburt's work should have put the controversy on the CO2 theory to an end, since "objections which have been raised against it by some physicists are not valid". Unfortunately, this paper passed almost unnoticed, I guess because meteorologists and geologists do not read Physical Review so often.
quote:
c). You also have to prove that it is a leading indicator, rather than a trailing indicator.
quote:
http://www.skepticalscience.com/co2-lags-temperature-intermediate.htm
Over the last half million years, our climate has experienced long ice ages regularly punctuated by brief warm periods called interglacials. Atmospheric carbon dioxide closely matches the cycle, increasing by around 80 to 100 parts per million as Antarctic temperatures warm up to 10°C. However, when you look closer, CO2 actually lags Antarctic temperature changes by around 1,000 years. While this result was predicted two decades ago (Lorius 1990), it still surprises and confuses many. Does warming cause CO2 rise or the other way around? In actuality, the answer is both.
nterglacials come along approximately every 100,000 years. This is called the Milankovitch cycle, brought on by changes in the Earth's orbit. There are three main changes to the earth's orbit. The shape of the Earth's orbit around the sun (eccentricity) varies between an ellipse to a more circular shape. The earth's axis is tilted relative to the sun at around 23°. This tilt oscillates between 22.5° and 24.5° (oblithis quity). As the earth spins around it's axis, the axis wobbles from pointing towards the North Star to pointing at the star Vega (precession).
The combined effect of these orbital cycles causes long term changes in the amount of sunlight hitting the earth at different seasons, particularly at high latitudes. For example, the orbital cycles triggered warming at high latitutdes approximately 19,000 years ago, causing large amounts of ice to melt, flooding the oceans with fresh water. This influx of fresh water then disrupted the Atlantic meridional overturning circulation (AMOC), in turn causing a seesawing of heat between the hemispheres (Shakun 2012). The Southern Hemisphere and its oceans warmed first, starting about 18,000 years ago. As the Southern Ocean warms, the solubility of CO2 in water falls (Martin 2005). This causes the oceans to give up more CO2, emitting it into the atmosphere. The exact mechanism of how the deep ocean gives up its CO2 is not fully understood but believed to be related to vertical ocean mixing (Toggweiler 1999).
The outgassing of CO2 from the ocean has several effects. The increased CO2 in the atmosphere amplifies the original warming. The relatively weak forcing from Milankovitch cycles is insufficient to cause the dramatic temperature change taking our climate out of an ice age (this period is called a deglaciation). However, the amplifying effect of CO2 is consistent with the observed warming.
CO2 from the Southern Ocean also mixes through the atmosphere, spreading the warming north (Cuffey 2001). Tropical marine sediments record warming in the tropics around 1000 years after Antarctic warming, around the same time as the CO2 rise (Stott 2007). Ice cores in Greenland find that warming in the Northern Hemisphere lags the Antarctic CO2 rise (Caillon 2003).
To claim that the CO2 lag disproves the warming effect of CO2 displays a lack of understanding of the processes that drive Milankovitch cycles. A review of the peer reviewed research into past periods of deglaciation tells us several things:
- Deglaciation is not initiated by CO2 but by orbital cycles
- CO2 amplifies the warming which cannot be explained by orbital cycles alone
- CO2 spreads warming throughout the planet
quote:
AGW has made the claim that CO2 is responsible for a dramatic increase in global temperatures. Al Gore famously said that the world would be uninhabitable by 2020. That the Arctic would be ice free by 2013, and that due to global warming we were going to add category 6 to hurricanes.
Arrant bullshit.
I agree, it is bullshit, Al gore is a politician, not a climate scientist. But just because he got some things clearly wrong, doesn't mean he didn't get some thing right
quote:
http://www.skepticalscience.com/al-gore-inconvenient-truth-errors-intermediate.htm
it's worth pointing out that Al Gore is a politician, not a climate scientist. Debunking Gore does not disprove anthropogenic global warming. Nevertheless, it is instructive to look at the purported errors in An Inconvenient Truth as it reveals a lot about climate science and the approach of his critics.
What Al got right
Retreating Himalayan Glaciers
Contrary to James Taylor's article, the American Meteorological Society's Journal of Climate never said growing glaciers are "confounding global warming alarmists" - that's a quote from the Heartland Institute website written by... James Taylor. He's actually quoting himself and attributing it to the AMS! To put the Himalayas in context, the original AMS study is not refuting global warming but observing anomalous behaviour in a particular region, the Karakoram mountains. This region has shown short term glacier growth in contrast to the long term, widespread glacier retreat throughout the rest of the Himalayas due to feedback processes associated with monsoon season. Overall, Himalayan glaciers are retreating - satellite measurements have observed "an overall deglaciation of 21%" from 1962 to 2007. In essence, the Karakoram glaciers are the exception that proves the rule.
Greenland gaining ice
Re Greenland, a big clue is the study's title: Recent Ice-Sheet Growth in the Interior of Greenland. The study finds increasing ice mass in the interior due to heavier snowfall - an expected side-effect of global warming - and doesn't factor in all the melting that occurs at the edges of the ice sheet. Overall, Greenland is losing ice according to satellite measurements here, here and here.
Antartica cooling and gaining ice
Antarctic cooling is a uniquely regional phenomenon. The original study observed regional cooling in east Antarctica. The hole in the ozone layer above the Pole causes increased circular winds around the continent preventing warmer air from reaching eastern Antarctica and the Antarctic plateau. The flip side of this is the Antarctic Peninsula has "experienced some of the fastest warming on Earth, nearly 3°C over the last half-century". While East Antartica is gaining ice, Antartica is overall losing ice. This is mostly due to melting in West Antarctica which recently had the largest melting observed by satellites in the last 30 years.
Hurricanes
The dispute isn't that global warming is causing more hurricanes but that it's increasing their severity and longevity.
What Al got wrong
Mount Kilimanjaro
Indeed deforestation seems to be causing Mount Kilimanjaro's shrinking glacier so Gore got this wrong. In his defence, the study by Philip Mote came out after Gore's film was made. But Mote puts it in perspective: "The fact that the loss of ice on Mount Kilimanjaro cannot be used as proof of global warming does not mean that the Earth is not warming. There is ample and conclusive evidence that Earth's average temperature has increased in the past 100 years, and the decline of mid- and high-latitude glaciers is a major piece of evidence."
Dr Thompson's thermometer
Al Gore refers to a graph of temperature, attributing it to Dr Thompson . The graph is actually a combination of Mann's hockey stick (Mann 1998) and CRU's surface measurements (Jones 1999). However, the essential point that temperatures are greater now than during the Medieval Warm Period is correct and confirmed by multiple proxy reconstructions. More on Dr Thompson's thermometer...
quote:
The point of all this: If you can't prove that AGW is caused predominantly by CO2 then measures meant to control Co2 are at best a waste of insufficient and at worse a waste of time.
We have, we wouldn't be having this debate if we haven't.
quote:
Skeptical science is wrong. As I said this is a global warming site. Go look at the snow and ice database which is where actual science is done.
It confirms that ice volume is UP.
I ask again, what kind of ice volume is up. Please enlighten me, as I can't seem to find the information you're discussing, so a link would mean the world to me.
quote:
I gave you the links in our private conversation. I showed you the equatorial temperatures, as well as the temperate and arctic. I also sent you links for temperature vs atmosphere altitude.
Since you brushed them off in our private conversations why bother providing them again.
Again, I suggest you try reading actual research, as opposed to continuing to rely on a nonscientific blogger site that only pushes a AGW bias. I read stuff from any source - whether NASA, MTO, NOAA, IPCC, NGIPCC regardless of the orgination. And look at the science. Rather than commentary on the science.
Lol, look at the science? Everything, every piece of information on Skeptical is referenced and linked to their original paper. When they refute denier arguments, they use the science and scientific research that has examined climate change to refute them and point out clear and obvious biases, like that ridiculous heartland institute. Dont believe me? Why not actually visit the website and check for yourself. The website isn't even a blogging site, it's designed to supply the information that refutes common denier arguments, like every single argument you've put forth. I swear by the time we're done I will have referenced every denier argument in the book, because you're running out of them.
You yourself haven't even provided links to any denier research papers, you've only linked me to articles or posted articles in my message box which rail against climate change but don't actually have any ground breaking research. They just complain and don't bring anything new to the table.
And I'll be honest I was talking to a couple slaves since you send me those messages and about a month ago I deleted a lot of my earlier messages in my inbox so I think they're gone, sorry :/
|
RE: A few facts about global warming/climate change. - 
Profile
New Messages
No New Messages
Hot Topic w/ New Messages
Hot Topic w/o New Messages
Locked w/ New Messages
Locked w/o New Messages
Post New Thread