Yahoo messing up with your question has proved to be very useful as there’s no way I would have got the comments from my previous answer and these additional comments into a single post. Your original question is still around, just not showing up on the list of open questions https://answersrip.com/question/index?qid=20100905144011AAe9Ezc&show=7#profile-info-20f3291b9320a302e9070bf55325531daa
Now had a read through your article. There’s a couple of technical points that could do with some attention but by and large the article is fine, I’ve also made some suggestions for the grammar and punctuation that you may wish to consider (hope you don’t mind)…
FROM: Some global warming 'skeptics’
TO: Some global warming skeptics
FROM: on the order of 1°C
TO: in the order of 1°C
FROM: and that therefore
TO: and therefore
FROM: a wide variety of methods
TO: a variety of methods
COMMENT: Planet Gore – is this the best source to link to?
FROM: Climate sensitivity describes how sensitive the global climate is to a radiative forcing (a change in the amount of energy reaching the Earth).
TO: Climate sensitivity describes how sensitive the global climate is to changes in the amount of energy reaching the Earth. It is generally expressed as the increase in the average global surface temperature that results from a doubling in the level of atmospheric carbon dioxide.
COMMENT: I think the description of CS needs to be expanded, when we talk about CS it’s normally more to do with a doubling of CO2 than just RF.
FROM: this will cause an energy imbalance (by trapping more radiation, causing more incoming than outgoing energy on Earth) enough to directly heat
TO: this will cause an energy imbalance by trapping more outgoing thermal radiation in the atmosphere, enough to directly heat
COMMENT: Distinguish which type of radiation. Also an energy imbalance won’t cause more incoming energy.
FROM: Climate sensitivity tells us the amount
TO: Climate sensitivity is the amount
COMMENT: The formula dT = λ*dF attempts to assign a specific value to the change in AGT, but this is a variable influenced by factors other than CS and RF. It may be better to change the formula to λ = dT÷dF. However, your formula will be adequate if you’re assuming a balanced state and a constant.
FROM: usually with units in Kelvin or degrees Celsius per Watts per square meter (°C/[W m-2]),
TO: usually expressed as °C(W/m²)
COMMENT: It’s awkward to express in words, I think if people are reading about CS they’ll know what °C W and m² are.
FROM: is different than the sensitivity to other radiative forcings
TO: differs from the sensitivity to other radiative forcings
FROM: like a change in solar irradiance
TO: such as a change in solar irradiance
COMMENT: “Climate sensitivity is a set value (approximately 0.8°C/[W m-2]),” This has me confused. CS isn’t ≈0.8°C Wm², I’m not sure what your value here relates to.
COMMENT: Possibly split the para… radiative forcing. [New Para] In other words
FROM: you're also arguing for a low climate sensitivity to solar irradiance, orbital changes, volcanic emissions, and everything else
TO: you're also arguing for a low climate sensitivity to other influences such as changes in solar irradiance, orbital variations and volcanic emissions.
FROM: the planet's average temperature changes on the order of 6°C (more like 8-10°C in the Antarctic)
TO: the planet's average temperature changes by 7°C to 10°C
FROM: The IPCC… put the possible range of climate sensitivity at
TO: The IPCC… summarised climate sensitivity as
FROM: climate sensitivity to a doubling of CO2 from anywhere between
TO: climate sensitivity from a doubling of CO2 to between
COMMENT: Possibly split the para… can be found here. [New Para] A study led by. And again… (Rahmstorf 2008). [New Para] Several studies
FROM: based on paleoclimate (historical climate change) data
TO: based on paleoclimatic (historical climate) data
FROM: has to be consistent with paleoclimate data.
TO: has to be consistent with paleoclimatic data.
COMMENT: The abbreviation Myr is an astronomical one, geologically it’s written myr (lowercase M). The norm is to use the abbreviation mya for million years ago, thus “about 55 Myr ago” becomes “about 55 mya”
FROM: may be higher than we currently believe, but it likely isn't lower.
TO: may well be higher than we currently believe.
FROM: Wigley et al
TO: Wigley et alia
COMMENT: One of the authors is female (Sarah Raper), thus it’s et alia (et al for the masculine, et aliae for the feminine, et alia for both or for neutral)
FROM: Forster et al. (2006) concluded as follows
TO: Forster and Gregory (2006) conclude as follows
COMMENT: Both are lead authors
FROM: Gregory et al
TO: Gregory et alia
REMOVE PARA: In 1988, NASA climate scientist…
REPLACE WITH: In 1988, NASA climate scientist Dr James Hansen produced a groundbreaking study, he produced a global climate model that calculated future warming based on three different CO2 emissions scenarios (A, B, and C).
COMMENT: Hyperlink the word study in the above edit
FROM: As he notes in Section 2 on page 2 of the study, Hansen's model assumed
TO: Now, after more than 20 years, we are able to review Hansen’s projections. His model assumed
FROM: with the total radiative forcing in reality being
TO: with the actual total radiative forcing being
COMMENT: Possibly split the para… emissions scenario. [New Para] The warming trend. And again… then scenario B [New Para] Therefore, what James Hansen’s
FROM: Therefore, what James Hansen's projections and assumptions and the measured real-world changes tell us
TO: Therefore, what Hansen's models and the real-world observations tell us
FROM: Annan et al
TO: Annan and Hargreaves
FROM: sensitivity is greater than 6°C
TO: sensitivity is in excess of than 6°C
COMMENT: Avoids duplicity of ‘greater than’
FROM: Annan concludes that
TO: Annan and Hargreaves concluded that
FROM: generally consistent with the range of
To: generally consistent within the range of
COMMENT: Re figure 4. The MIT study assigns a very high increase in levels of CO2 emissions that aren’t all that reflective of reality. The bulk of their projected increase is based on socio-economic reasons and therefore implies a higher per capita emission level. In fact, per-capita emissions have remained more or less level for about 20 years now, which contradicts the assumptions of the MIT report. The main driver of increased GHG emissions is population increase. With a population of 6.81 billion we’re increasing CO2 ppmv by 20 per decade at present. By 2050 the estimated pop will be 9.1bn and therefore likely to increase CO2 ppmv by 27 per decade. This is an ave increase of 23.5ppmv for each of the next 4 decades thus raising CO2 levels from the present 394 to 488ppmv. With a cumulative decadal increase of 1.4ppmv over and above the present 20 then it will be 2076 by the time CO2 reaches 580ppmv. CO2 has risen ≈78ppmv in the last 50 years, it would have to increase 266% to reach 580ppmv by 2050.
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A few minor points, otherwise an excellent article that clearly demonstrates that CS is closer to the 3°C mark than some of the unreasonably low figures that sometimes get mentioned. I’ve bookmarked the page and when I get round to sorting my bookmarks out (there’s thousands of them all jumbled together) then I’ll be sure to link to it in the future.
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COMMENT: TO ANDY
Absorption Bands – d/dx has covered this perfectly.
Water Vapour – Definitely not doubled since c1850, not even close. The saturation fraction of water in air is 1% at 14°C (the average global temp in 1850), to have doubled the ave global temp would need to increase to 22°C. It hasn’t, it’s increased to 15°C.
Ice Ages – The temp fluctuations of 6°C to 10°C are consequent to the entering and exiting of ice-ages, an event that is caused by the variations in Earth’s orbital eccentricity or circularity around the Sun.