Modern Anthropogenic Global Warming in 5 minutes
Remarks to the Citizens’ Panel on Carbon Dioxideorganized by the Nevada Conservation League
Jun 13, 2012
I want to make a few remarks about the science of global warming. Among climate scientists, this is not a controversial topic. But among the general public, it IS controversial. I’m going to explain why climate scientists think that human activity is warming the Earth.
I want to start with the greenhouse effect. Carbon dioxide in the atmosphere warms the Earth. CO2 and water vapor are greenhouse gases.
Without any greenhouse gases in the atmosphere, the Earth would be very cold: Cold enough to freeze water. The size of greenhouse effect is 59 F. Earth would be frozen over. The Earth has had a greenhouse effect for billions of years.
Since the Industrial revolution, burning fossil fuels - coal and oil and natural gas (methane) - has increased the level of CO2 in the atmosphere. The level is now 40% higher than pre-Industrial revolution. This makes a stronger greenhouse effect.
This is not a long complicated chain of reasoning. Greenhouse gases warm the Earth, and more greenhouse gases produce a stronger greenhouse effect, and global warming. The greenhouse effect was understood, in principle, almost two centuries ago. It is not new science.
The scientific question is: how hot will it get? Will it get hot enough to create a problem?The answer has become clear in the last few decades: if CO2 continues to increase and increase, the temperature will increase enough to cause an environmental disaster. "Business as usual" will lead to disaster, sooner or later.
Let’s go down the check list.
CO2 in atmosphere is going up. The temperature going up. The polar icecaps are melting. Sea level is rising, and the rate of sea level rise is accelerating. The ocean becoming acid because CO2 dissolves in the ocean, making carbonic acid. This has been observed and is accelerating.
How do we know that humans are causing it?
It's NOT the Sun, for two reasons:
(1) In recent decades, the sun’s output has been rising and falling by small amounts, with no long term trend,
(2) If it were the Sun, we would see warming of the Earth’s surface AND warming of upper atmosphere.
If it's the greenhouse gases in the atmosphere, then you expect to see warming of the surface, and a COOLING of the upper atmosphere. And that’s what we do see.
Modern manmade global warming explains an enormous number of facts that are difficult or impossible to explain any other way.
Let’s hear from an unlikely source, a chemical engineer at Mobil Oil. The The oil companies and other big corporations had a “Global Climate Coalition”, which had a technical committee, headed up by L. C. Bernstein, a chemical engineer (Mobil Oil). In a confidential memorandum in 1995, the committee advised the oil company,
"the scientific basis for the greenhouse effect and the potential impact of human emissions of greenhouse gases such a CO2 on climate is well established and cannot be denied." So while the oil companies and their hired hands were saying in public that global warming isn’t happening, it’s all a hoax, etc., their own scientists were telling them just the opposite in private: global warming is real, caused by the greenhouse effect.
What to do about it?
We need to get energy from non-carbon sources
NOW: the main sources of the energy are coal, oil, natural gas
FUTURE: solar, wind, hydro, geothermal, nuclear
ALSO: conservation, although this is not enough by itself.
Non-carbon sources are more expensive than fossil fuels, judged just by the market. Environmentalists sometimes don't want to say it's more expensive than fossil fuels. But really we need to take into account the total cost, including the high cost of doing nothing.
Alternative energy is expensive - how could be it be cheap when you’re replacing every oil well and every coal mine in he world - but not as expensive as doing nothing.
The cost to US: about half of military budget, which needs to be redirected to renewable energy.
Think of this as an insurance policy, insurance against catastrophic global warming. We need to pay the insurance premium. You get to have fire insurance, in case your house catches fire.
DO you buy fire insurance because you are completely convinced that you house will catch fire?
NO. You buy fire insurance because you can't be sure that your house WON'T catch fire.
Our national policy is doing nothing. BOTH the Obama administration and the GW Bush administration policy is doing nothing to get away from carbon dioxide.
We need to make a transition to non-carbon sources to preserve the habitability of the Earth for the sake of our children and our children's children.
This event received press coverage in the Las Vegas Sun newspaper.
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31 comments:
You can't say it much more simply than that.
And if humans can't collectively respond when confronted with such a simple message, it just goes to show that we're not as intelligent as a species, as we imagine. In that case, evolution will sort it out - by consigning Homo sapiens [sic] to the extinction bin.
Bernard J. Hyphen-Anonymous XVII, Esq.
It's not getting hotter.
Hardy Cross
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Hardy Cross
Typo:
"Let’s hear from an unlikely source, a chemical engineer at Mobil Oil..."
Should read
"Let’s hear from the profession best placed to help solve the issues, a chemical engineer at Mobil Oil..."
Just sayin.
Quod erat demonstrandum.
Bernard J. Hyphen-Anonymous XVII, Esq.
Note that the military is trying to get off fossil fuel, but Congress isn't helping them.
I heard a fine talk by Admiral Gary Roughead (Ret), who was Chief of Naval Operations, started a climate task force and an energy task force.
This was at at Stanford, and the videos ought to be up in a few weeks. George Shultz was amazing as always. He was happy with his Nissan Leaf, which he charges from his solar panels.
Indeed,
This is a great succinct call to action. I might use such an approach when discussing AGW to the general public.
I'm not surprised that the top bunnies weeded out the oogie-boogie ad for hocus-pocus, but now my Q.E.D. seems rather detatched!
Bernard J. Hyphen-Anonymous XVII, Esq.
@ Hardy Cross
It's not getting hotter.
Whoever said the warming would be monotonous? Natural variation hasn't stopped. That's just wishful thinking (or perhaps outright denial) on your part.
Ye olde long term trend is the thing to watch.
BBD
Not getting hotter? The last 12 months are the hottest on record?
Hmm..
US CO2 emissions are decreasing.
Doing nothing seems to be better than doing something.
It is probably time for hysterics to stop hiding behind answering "Is it warming?" (It is) and seriously be held accountable for answering 'How much?' and 'Who cares?'
( not much and and only hysterics )
Eunice
The oddly familiar-sounding 'Eunice' brings us some very familiar false equivalence:
US CO2 emissions are decreasing
But Eunice, dear, the US is not the world. And *global* emissions are rising as rapidly as ever. Here's a pretty picture for us to marvel at together. We can also pause to recollect that US emissions are falling because:
- its economy is all buggered up
- much has been offshored to Johnny Foreigner
It is probably time for hysterics to stop hiding behind answering "Is it warming?" (It is) and seriously be held accountable for answering 'How much?' and 'Who cares?'
Of course it's your own business what you care about. But please don't mind if people who understand that this is but the overture dismiss you as a witless pillock.
BBD
Off-topic, but in the aftermath of the release of utterly disgusting abusive emails sent to Dr Phil Jones of CRU and others, the Skeptical Science website is sending him a supportive letter. You can add your comment and 'signature' here ...
http://www.skepticalscience.com/Nil_Illegitimi.html
BBD:
But Eunice, dear, the US is not the world. And *global* emissions are rising as rapidly as ever. Here's a pretty picture for us to marvel at together.
I guess you missed the author bemoaning US inaction. Oh well.
We can also pause to recollect that US emissions are falling because:
- its economy is all buggered up
- much has been offshored to Johnny Foreigner
Pause a little longer and you'll take in the fact that CO2 and economic well being appear linked. You might even reflect that increasing energy costs are likely to further 'bugger' up.
You might even observe that increasing US energy costs would only further offshoring.
Eunice.
BBD:
Of course it's your own business what you care about. But please don't mind if people who understand that this is but the overture dismiss you as a witless pillock.
Dismiss if you wish, but that won't change the facts that:
The observed temperature trends since 1979 are less than the 'Low End' Scenario of IPPC4
The observed temperature trends since 1979 are less than Hansen scenario C.
The observed temperature trends since 1979 are less than the A1B multi model mean.
The observed temperature trends since 1979 are close to the trend from 1910 through 1945 which we may call more 'natural'.
The contemporary 'warming' remains small compared to the climatic variation of the Holocene Climatic Optimum, which corresponds to the popularly conceived founding of civilization.
Orbital variations will yield much warmer than present Northern and especially Arctic summers for most of the next one hundred thousand years.
The benefits of a warming planet, for however brief we may be able to help advance it, may very well outweigh the detriments, but neither are necessarily significant given the variations humans ( and all species ) have encountered.
deny if you wish, but these are the facts.
Eunice
@ Eunice
The Keeling curve is not really a pretty picture at all. If you risk a peek at the link, you will see why. The object of the game is to stop the wiggly line going up, and up, and up...
US inaction has global policy ramifications. It's not what you might call leading by example. Here in the UK we have do at least have the rhetoric all shipshape and Bristol fashion.
Dismiss if you wish, but that won't change the facts
Or we could look at it another way...
The observed temperature trends since 1979 are less than the 'Low End' Scenario of IPPC4
Aerosols and oceans. Do keep up :-)
The observed temperature trends since 1979 are less than Hansen scenario C.
Well, ModelE was a teeny bit crude and it did have a sensitivity of 4.2C. You could say that it did surprisingly well and the results support an equilibrium sensitivity of ~3C - which is generally held to be the most likely value these days.
The observed temperature trends since 1979 are less than the A1B multi model mean.
Aerosols and oceans. Give it time.
Orbital variations will yield much warmer than present Northern and especially Arctic summers for most of the next one hundred thousand years.
Yes, the 400ka eccentricity minimum is with us again, and yes, the Holocene could be a prolonged interglacial like MIS 11. No, Northern and Arctic summers will not be 'much warmer than the present' for 'most of the next 100ka'.
Poor Milutin will be spinning in his grave so fast he won't know his precession from his obliquity.
deny if you wish, but these are the facts.
In addition to the other stuff, you assert, as a fact, that warming will be beneficial and insignificant compared to (presumably) Holocene variation. Which means that you don't really get it. Waving the Holocene Thermal Maximum around as if it mattered in this context is to miss the point to an absurd degree. This isn't the place for a long, pointless 'discussion' that won't go anywhere anyway, so let's leave it at that.
BBD
BBD
SO2 has been declining for more than a decade do keep up.
And ocean consumption of thermal energy is an argument for temperature rise to continue to be minimal.
Yes, Northern and Arctic summers will be much warmer than present for most of the next one hundred thousand years unless you've concocted a new mechanism whereby increased insolation is irrelevant to surface temperature.
And yes the HCO is extremely relevant as a measure of what humans and all life on the planet experienced.
Getting emotional and exaggerating climate change and impacts may be appealing, but the reality is much more boring.
Eunice.
Why yes, SO2 has been declining for decades because of effective (somewhat) regulation and a cap and trade market many places. The same mix would work for CO2
Do you do poework?
Eunice,
At present 54% of the Continental US is in drought. And the El Nino just started this month. Does that sound negligible to you?
@ Eunice
SO2 has been declining for more than a decade do keep up.
Ah, not so. First, remember that the US is not the world. Second, there is Chinese coal (Hofmann et al. 2009). Then there's equatorial volcanism and the Brewer-Dobson circulation(!) (Vernier et al. 2011). I do take the point that clean air legislation reduced SO2 emissions somewhat up to the 1990s, quite possibly strengthening the 1998 El Nino (that's that huge spike in GAT with a giant cherry perched on top). But there's strong evidence that stratospheric sulphate loading has increased since.
And ocean consumption of thermal energy is an argument for temperature rise to continue to be minimal.
It's not a let-out clause. Actually, this is interesting. The scientific debate is exemplified by Trenberth on the one hand and Hansen on the other. Trenberth argues that energy is accumulating in the deep ocean and this will periodically slow or even halt warming. Hansen suggests that the negative aerosol forcing has been underestimated and that most models over-estimate the rate at which heat perturbations are mixed into the deep ocean (Hansen et al. 2011).
It's perfectly possible that both arguments have merit. There's lots to sort out. But nobody serious claims that the last decade of flat global mean temperatures 'falsifies AGW'.
Yes, Northern and Arctic summers will be much warmer than present for most of the next one hundred thousand years unless you've concocted a new mechanism whereby increased insolation is irrelevant to surface temperature.
Repeating something incorrect does not fix the problem. But perhaps references will clear this up. Where are you getting this from?
And yes the HCO is extremely relevant as a measure of what humans and all life on the planet experienced.
The HCO/HTM ended ~5ka. Present concern is what a *rapid >2C warming* will do to established, large-scale human agriculture, coastal populations and ecosystems unable to move or adapt fast enough to cope with rapid warming. This was false equivalence yesterday and it's false equivalence today.
BBD
The same mix would work for CO2
With carbon markets failing, I guess there are a lot more hot air hypocrites than true believers.
But wasting a lot of money to reduce beneficial gasses is a pretty hard sell.
Eunice.
BBD:
Google a little harder - global SO2 emissions have been declining for more than a decade. This means rather than cooling, the effect from change in SO2 should have been additional warming.
You may also note - I affirmed, not denied AGW - emissive gasses should tend to impose warming. However, exaggerating the extent, impacts, certainty, and risks versus benefits is hysteria, not science.
You can google solar variation or Milankovitch quite ably to observe future intensity and duration of summer sunshine in the NH and Arctic.
The HCO had millenia of such longer, hotter summers (and commensurate colder winters) in the NH but this was a time of human advancement.
Eunice
and evidently Polar bear survival
Dilbert,
All the other droughts in the past were natural, but this one is CO2?
eunice
@ Eunice
You are repeating yourself without apparently reading the references provided. Repeating yourself is not sufficient. Reading is both a courtesy and necessary for a productive exchange.
I've already told you that the following statement is incorrect:
Northern and Arctic summers will be much warmer than present for most of the next one hundred thousand years
Your only chance to defend this extraordinary claim was to provide references. You have refused. Now everybody knows you are bullshitting.
BBD
"US CO2 emissions are decreasing."
Geographically from the USA, yes, but globally are they really? How much has been offshored? Would you claim a financially successful US company using factories in China to make its products is actually bankrupt?
As for benefits from more warming, your confidence could be somewhat misplaced.
Requiem for the sea: State of the Seas report concludes “negative changes” to the oceans exceed IPCCs worst case scenarios.
Main points from the PDF of Rogers, A.D. & Laffoley, D.d’A. 2011. International Earth system expert workshop on ocean stresses and impacts. Summary report. IPSO Oxford, 18 pp.
• Human actions have resulted in warming and acidification of the oceans and are now causing increased hypoxia.
• The speeds of many negative changes to the ocean are near to or are tracking the worst-‐case scenarios from IPCC and other predictions. Some are as predicted, but many are faster than anticipated, and many are still accelerating.
• The magnitude of the cumulative impacts on the ocean is greater than previously understood
• Timelines for action are shrinking.
• Resilience of the ocean to climate change impacts is severely compromised by the other stressors from human activities, including fisheries, pollution and habitat destruction.
• Ecosystem collapse is occurring as a result of both current and emerging stressors.
• The extinction threat to marine species is rapidly increasing.
The participants concluded that not only are we already experiencing severe declines in many species to the point of commercial extinction in some cases, and an unparalleled rate of regional extinctions of habitat types (eg mangroves and seagrass meadows), but we now face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation. Unless action is taken now, the consequences of our activities are at a high risk of causing, through the combined effects of climate change, overexploitation, pollution and habitat loss, the next globally significant extinction event in the ocean. It is notable that the occurrence of multiple high intensity stressors has been a pre-requisite for all the five global extinction events of the past 600 million years (Barnosky et al., 2009).
* Carbon Dioxide Enrichment Inhibits Nitrate Assimilation in Wheat and Arabidopsis. Bloom et al (2010).
* Sharply increased insect herbivory during the Paleocene–Eocene Thermal Maximum. (Currano 2007)
* Insects Will Feast, Plants Will Suffer: Ancient Leaves Show Affect Of Global Warming.
* Grassland Responses to Global Environmental Changes Suppressed by Elevated CO2. (Shaw 2007)
* Photosynthetic inhibition after long-term exposure to elevated levels of carbon dioxide. (DeLucia 1985)
* Insects Take A Bigger Bite Out Of Plants In A Higher Carbon Dioxide World.
* Crock of the Week - Don't it make my Green World Brown
Eunice is a typical "lukewarmer". It ignores the reality of drought and mistakes fetid for fertile. Dumb.
I wonder if Eunice has read and carefully considered Jörg Zimmermann's discussion of Shakun et al. (2012) that Eli posted above on 05 July?
BBD
Would anybunny be interested in the companion piece by Georg Hoffman?
Definitely a yep. Please.
Yes please Eli, if it isn't too much trouble.
BBD
Get ready to rub your eyes in disbelief.
FOX News: Climate Scientist Explains Record Temperatures.
Ummm... Michael Mann, interviewed by Alan Colmes. Not a Heartland fellow or Pat Michaels in sight.
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