Am I Gobsmacked or what?
Is this true? If so, what is the Warming hypothesis?
I am stunned, and maybe just a little nervous to think I have been listening to all my physics friends wax eloquent on the Green House effect of carbon dioxide–yada yada, and how it is a given that increased carbon dioxide in the air will cause some warming, just not as much as the fanatics predict.
I always conisdered myself a student on the astrophysics, but never read something like what Lofthus is positing.
http://www.americanthinker.com/2014/04/global_warming_and_settled_science.html
John, he isn’t quite saying what you think he’s saying.
This is effectively a clean and simplified description of the Greenhouse Gas Effect. There is only one number in this article that I disagree with, and that’s the “0”. Gas absorption of radiation is an Arrhenius function (e^(1-a/c) where a is a constant, c is concentration, and e is 2.71…), and those never hit 100%. Something always slips through. This has been mentioned multiple times that the CO2 absorption band is near-saturated. It might be effectively saturated, but it’s not completely. On a basic level, it can’t be.
So the greenhouse gas effect is real and existent. We are just disagreeing about whether it is already maximized. That’s a significant difference that cannot be ignored.
(***) Of course, the clouds of SO2 top out at more than twice that altitude (-40C / ~0.01Bar), so that’d be a minor engineering issue, what with the whole lack of light and the acid clouds eating away at everything including the crops themselves. But hey, if we can figure out the massive anti-gravity systems, the stabilizers to compensate for the winds at that altitude, and also the economic transportation of everything into/out of the planetary gravity well and out to the rest of the system… heck, those clouds should be just a minor thing, ya….?
Dudes. Venus is a totally gnarly place. Let’s not go there much.
(**) Another incidental point of interest: the average temperature of the Venusian atmosphere (CO2 content ~965,000ppm) at an altitude of 50 – 55km (where the pressure is roughly equal to Earth surface) is about 20 – 40 deg. C. If one needed to feed a solar system-wide empire, I’d find a way to do it with floating farms on Venus, a la a “Cloud City” -type setup(***) from The Empire Strikes Back.
(*) A chart of atmospheric absorption wavelengths may be found here: (http://en.wikipedia.org/wiki/File:Synthetic_atmosphere_absorption_spectrum.gif). A chart showing water only over much of the EM spectrum may be seen here: (http://www1.lsbu.ac.uk/water/images/watopt.gif).
Just as a matter of interest, water vapor absorbs even more strongly in much of the radio & microwave bands below the IR. Radio trasmission specialists familiar with the Ka & Ku bands will note that those frequency ranges are above (Ka) and below (Ku) the K frequency band which is opaque to transmission (the red peak in the second linked chart) due to absorption by the third most plentiful gas in the Earth’s atmosphere (argon is ~1% by volume, H2O = ~2%). Not totally germane to the discussion, but interesting.
Lofthus’ premise — that all available LWIR from the earth is absorbed already by existing CO2 — has been scientifically & mathematically demonstrated many times over, and is really nothing more than basic laboratory physics writ large (Bill Nye’s apparent unfamiliarity notwithstanding).
However, that same premise may be extended further to include a far more prevalent (and more effective) greenhouse gas: water vapor. In addition to the bands CO2 absorbs, H2O also absorbs in the LWIR spectrum, and does so over a wider range.(*) It is also a far more plentiful gas(~20,000ppm on average) than CO2 (~400ppm) in the troposphere. Like CO2, gaseous H2O easily has the capacity to absorb ~100% of the LWIR emitted by the Earth. Thus, worrying about the greenhouse effect of additional CO2 in the atmosphere (or any at all, for that matter) is really like worrying about the thickness of the second coat (just the 2nd coat, mind) of latex paint on the inside of an already boarded-up window.
Put another way, the Earth would need to move to a spot somewhere near Mercury’s orbit(**) in order to receive enough insolation to get hot enough to then re-emit enough IR to wonder whether or not current levels of GHGs would be able to totally absorb them. Of course, should such an event occur, not only would the peak emission frequency of the Earth change — potentially removing CO2 entirely from the discussion — I am unconvinced that anyone will really be worrying very much about the absorbtion of out-going long-wave infrared…
“Coppertone Brand SPF 200,000: When lead melts, you won’t!”
The problem with the term “global warming” is the connotations which follow in its wake, i.e., “global warming” usually equates to some variation of “the whole Earth is getting dangerously hotter and it’s the fault of human beings.” This is why when people ask me something along the lines of “Do you believe in global warming,” I always ask what they mean before answering.
But the scientific point in question is not whether any overall warming exists or has taken place over the last century or two (it does/has), but rather if carbon dioxide and other greenhouse gases have any significant role as a driver of the warming observed over that period. Lofthus’ premise is that they do not, based upon known facts and repeated observations.
Hey Geologist, you missed what the guy said, he said that the GHG theory was bunkum, then Roy Spencer explained why Lofthus didn’t understand the theory of how carbon dioxide is a green house gas, has to do with the EM spectrum but you are a geologist.
Shall we talk about the Minoan warming and then a cooling, the Roman, Warming, or the Medieval? Or should we talk about more ancient periods and such?
You say the earth is warming, you bet, since the Little Ice Age of the 16th to the 18th century. You’re a geologist–think in terms of millenia and eons and periods and epochs and ages and such–was there a time in the past when carbon dioxide was at an ambient level of more than 5000 parts per million? Yep. And were there times in the past when the earth’s average temp was warmer than the current 57 F, and aren’t we in a cool period right now as far as more recent history of geological time goes?
Lofthus had a proposal for the theory of Green House Gases that has since been contradicted by Spencer,on the physics, but the debate is still on about carbon dioxide as a driver of warming for other reasons. .
You should know that, being a geologist, like a really big picture historian.
Before there were suvs and industrial development on earth, there was higher carbon dioxide and warmer climate.
Fascinating stuff.
Table of Geological Periods
It is generally assumed that planets are formed by the accretion of gas and dust in a cosmic cloud, but there is no way of estimating the length of this process. Our Earth acquired its present size, more or less, between 4 billion and 5 billion years ago. Life on Earth originated about 2 billion years ago, but there are no good fossil remains from periods earlier than the Cambrian, which began about 490 million years ago.
The known geological history of Earth since the Precambrian Time is subdivided into three eras, each of which includes a number of periods. They, in turn, are subdivided into epochs and stage ages. In an epoch, a certain section may be especially well known because of rich fossil finds.
New Geological Period
In March 2004, geologists added a new time period to Earth’s chronology—the Ediacaran Period. The Ediacaran Period lasted about 50 million years, from 600 million years ago to about 542 million years ago. It was the last period of the Precambrian’s Neoproterozoic Era. Multicelled organisms first appeared during this time. This period is the first new one added in 120 years.
Precambrian Time
The Precambrian’s lower limit is not defined, but ended about 542 million years ago. The Precambrian encompasses about 90% of Earth’s history.
Period Duration1 Epochs Events
Cambrian (Cambria, Latin name for Wales) 54 Lower Cambrian
Middle Cambrian
Upper Cambrian Invertebrate sea life proliferating during this and the following period
Ordovician (Latin Ordovices, people of early Britain) 45 Lower Ordovician
Upper Ordovician Diverse marine life, including vertebrates; vascular plants
Silurian (Latin Silures, people of early Wales) 28 Lower Silurian
Upper Silurian Coral reefs; giant scorpions; first jawed fish
Devonian (Devonshire in England) 57 Lower Devonian
Upper Devonian Numerous fishes, other sea life; many plants, first trees; wingless insects
Carboniferous (Latin carbo = coal + fero = to bear) 60 Upper, Middle, and
Lower Mississippian2
Upper, Middle, and
Lower Pennsylvanian2 Maximum coal formation in swampy forests; insects, amphibians, reptiles; fishes, clams, crustaceans
Permian (district of Perm in Russia) 48 Lower Permian
Upper Permian Large reptiles, amphibians; most species become extinct
1. In millions of years.
2. Mississippian and Pennsylvanian names are used only in the U.S.
Mesozoic Era
This era began 251 million years ago and lasted about 186 million years. The name was compounded from Greek mesos (middle) and zoön (animal). Popular name: Age of Reptiles.
Period Duration1 Epochs Events
Triassic (trias = triad) 51 Lower Triassic
Middle Triassic
Upper Triassic Early dinosaurs, crocodiles, turtles; first mammals
Jurassic (Jura Mountains) 54 Lower Jurassic
Middle Jurassic
Upper Jurassic Many seagoing reptiles; early large dinosaurs; later, flying reptiles (pterosaurs), earliest known birds
Cretaceous (Latin creta = chalk) 80 Lower Cretaceous
Upper Cretaceous Dinosaurs and other reptiles dominate; seed-bearing plants appear
1. In millions of years.
Cenozoic Era1
This era began 66 million years ago and includes the geological present. The name was compounded from Greek kainos (new) and zoön (animal). Popular name: Age of Mammals.
Read more: Table of Geological Periods | Infoplease.com http://www.infoplease.com/ipa/A0001822.html#ixzz2zp6XRZ4M
“If global warming even exists”??? Please check in with your neighborhood geologist about global temperatures are recently as the Oligocene (during the Cenozoic – the time of “Recent Life”. Or what the global temperature was when Mankind first arrived in North America.
Yes, the Earth is warming.