GC - I'vechallenged you before to provide examples of Dr Mann's scientific malfeasance. Still waiting.

Making unfounded accusations is not a good look.

Let's do a thought experiment: imagine a world in which the HS studies had never been published. The case for AGW would be identical.

Erm…. No. For a start, the Mediæval Warm Period and Little Ice Age would still be acknowledged, as would the fact that the longer-term trend of cooling is still ongoing.

Except the hockey stick does have an LIA, a generally cool period with a minimum around 1450AD. As MBH99 only went back to AD1000, it missed the first part of the MWP, which was in any event seems to have happened at differing times in different parts of the globe, and not been as warm as today.

In any event, the proposal that the globe has been warm due to natural causes therefore current warmth cannot be manmade is an obvious logical fallacy. The case for AGW remains intact.

Ongoing cooling? Where?

Phil Clarke, Radical Rodent beat me to it.

How did Mann lose the MWP and the LIA?

For somebody quick to accuse people of being liars, why are you demonstrating more sensitivity, than the Climate does to CO2?

All Mann has to do, is provide evidence. Preferably in Court, involving Legal Action that HE has instigated, but now delays. Until then, he is merely blustery, as are you, and the rest of Climate Science.

Is your faith in AGW why you were so impressed with Gergis 2016, that Climate Science has not withdrawn or retracted despite the Lies?

Sorry, I wanted actual examples.

which implies that the flat line of the infamous hockey stick should not have been flat, but, at the very least, inclined

It is.

Medieval Warmth in Greenland is acknowledged, but Greenland is not the world.

The reconstructed MCA pattern is characterized by warmth over a large part of the North Atlantic, Southern Greenland, the Eurasian Arctic, and parts of North America, which appears to substantially exceed that of the modern late– 20th century (1961–1990) baseline and is comparable to or exceeds that of the past one-to-two decades in some regions. […] Certain regions, such as central Eurasia, northwestern North America, and (with less confidence) parts of the South Atlantic, exhibit anomalous coolness. The LIA pattern is characterized primarily by pronounced cooling over the Northern Hemisphere continents, but with some regions—e.g., parts of the Middle East, central North Atlantic, Africa, and isolated parts of the United States, tropical Eurasia, and the extratropical Pacific Ocean—displaying warmth comparable to that of the present day.

Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly

Science 326

Sorry, I wanted actual examples.

Jan 31, 2018 at 12:41 PM | Phil Clarke

The whole world is waiting for some evidence of AGW. You quote sources devoted to Mann.

Mann "projected" an uptick. We got a pause.

Which bits of Climate Science are worth keeping, because otherwise it will all be thrown away. I have politely asked you before, but you are unable to work it out yourself.

Mann "projected" an uptick. We got a pause.

Ah, finally, a fact. When and where did he make this projection?

Could someone explain why relatively small amounts of CO2 would have a larger impact than H2O as a GHG when H2O is much more prevalent?

See that is what I do not get. There is about 125x more H2O in the atmosphere than CO2 and H2O is more broad spectrum than CO2 when it comes to absorbing radiation at various frequencies.

Now I've heard one (IMHO faulty) explanation, which is that H2O stays in the atmosphere for a much shorter duration than CO2. But even if so, that is irrelevant because it is the concentration that matters. How long a single molecule stays is irrelevant when there is simply much more added, much more often.

So one would expect H2O to have several hundred times more impact than CO2 as a GHG. Right?
And if not, why not?

JayJay

Sometimes the water vapour goes away, but the CO2 stays. CO2 is a forcing wholesaler vapour is a feedback

The amount of water vapour in the atmosphere is controlled by the temperature. Water vapour in the atmosphere increases as global temperatures rise and it's increased greenhouse effect amplifies the temperature rise. When temperatures fall the opposite occurs.

Simplifying somewhat, an increase in temperature of 1C due to the CO2 greenhouse effect will evaporate enough water vapour to add another 2C due to the water vapour greenhouse effect.

Reduce the CO2 enough to reduce its direct warming effect by 1C and water vapour would decrease by enough to amplify the total cooling to 3C.

That is why water vapour has a greater greenhouse effect than CO2 but does not itself control the climate.

Mann "projected" an uptick. We got a pause.

Ah, finally, a fact. When and where did he make this projection?

Jan 31, 2018 at 2:39 PM | Phil Clarke

Are you denying Mann's Hockey Stick?

Mar 5, 2018 at 3:53 PM | Entropic man

So why hasn't it worked like that, with CO2 rising?

Entropic:

"Sometimes the water vapor goes away, but the CO2 stays. "

I'm not so much concerned with the expected lifetime of a single H2O or CO2 molecule, what matters IMHO is the concentration in the atmosphere.

https://www.ucsusa.org/global-warming/science-and-impacts/science/CO2-and-global-warming-faq.html

Water vapor is the most abundant heat-trapping gas, but rarely discussed when considering human-induced climate change. The principal reason is that water vapor has a short cycle in the atmosphere (10 days on average) before it is incorporated into weather events and falls to Earth, so it cannot build up in the atmosphere in the same way as carbon dioxide does.

To me it seems pretty irrelevant that H2O only stays in the air for 10 days and CO2 for much much longer, because that is the half time of a single molecule. What matters is the average concentration.
Sure it is much easier to get that increased with CO2, but in the end it is just a matter of supply & demand, or better a matter of addition and removal of the GHG.

As you said:

"The amount of water vapour in the atmosphere is controlled by the temperature. Water vapour in the atmosphere increases as global temperatures rise and it's increased greenhouse effect amplifies the temperature rise. When temperatures fall the opposite occurs."

Sure the maximum concentration is controlled by temperature, but that is not the only way the actual concentration of H2O in an area is changed, that can happen independently (at least until saturation, given a certain temperature).
Of course we need to increase the production of H2O on a (semi-)pertinent basis in order to notice a difference, simply because the relatively short life-expectancy of H2O in the atmosphere.
But we can do that by (say) increasing agriculture, which needs water, and certainly when we need to use irrigation.

Of course the moisture levels may increase to such an extent that at some point we get clouds (given temperature, wind, dust-particles in the air etc), which will reduce temperatures and/or until those clouds start to rain out. After that the cycle starts again.
The point is that over the year the average moisture levels over the entire area (and proably further out, due to wind etc) will be noticeable higher than without irrigation.

We have had a huge increase in global population over the last century, and all those people needed to eat. We have had huge areas newly or additionally developed for agriculture, including irrigated lands, such as in the USA, the EU, India and China. Also in many other area's (say in Africa) although it seems that a lot of food in the overpopulated countries is coming from USA or EU (or elsewhere).

This must have had a noticeable effect. I know that moisture levels in the atmosphere are noticeable higher in areas that are being irrigated. I assume this will be true for any area where there is intensified use due to agriculture. And certainly in the dryer area's that needed irrigation the air will not have been saturated with moisture prior to the irrigation (or else irrigation would not have been required).

So then H2O levels in the atmosphere must have been increased quite a bit over the last century or so, and this must have had an noticeable effect on the global average temperature. I do not see why this is not the case.

Simplifying somewhat, an increase in temperature of 1C due to the CO2 greenhouse effect will evaporate enough water vapour to add another 2C due to the water vapour greenhouse effect.
(...)
Mar 5, 2018 at 3:53 PM | Unregistered CommenterEntropic man

"....will evaporate enough water vapour (sic) to add another 2C due to the water vapour greenhouse effect."

Which will then evaporate enough water (note that it's the liquid that is evaporated, not the vapour) to add another 4C due to the water vapour greenhouse effect.

Which will then evaporate enough water to add another 8C due to the water vapour greenhouse effect.

Which will then evaporate enough water to add another 16C due to the water vapour greenhouse effect.

etc

JayJay

As I said, my comment was simplified. There are devils in the detail and other feedbacks which make things more complex. Irrigation would indeed increase local humidity, and have some extra warming effect.

Based on the physics you would expect the amount of water vapour, the absolute humidity, to increase by 4% per degree of warming.

Look at the temperature record and you see an increase in global temperature of about 1C since 1880 and a current rate of increase between 0.13 and 0.2C per decade depending on which dataset you choose. Of that about 1/3 would be directly due to CO2 and 2/3 to other factors, mostly water vapour . In energy terms that would be an extra 1.2W/M2 worldwide from the CO2 GHEand 2.4W/M2 from the water vapour GHE over 138 years.

Glowworm

The effect is sigmoid, not exponential. As JayJay said, It is self-limiting because extra water vapour leads to extra low cloud cover. That reflects some energy back to space and eventually cancels out all the extra water vapour GHE warming.

You end up with an equilibrium at a higher temperature than you started with, but no runaway warming.

Radical rodent

Not quite. We have had an increase of about 0.33C due to CO2 amplified to 1C by the effect of extra water vapour etc.

https://wattsupwiththat.com/2018/03/05/will-congress-finally-get-tough-on-junk-science/

"A growing problem for modern industrialized Western societies is the legion of government agencies and unelected bureaucrats and allied nongovernmental organizations that seem impervious to transparency, accountability or reform. Their expansive power often controls public perceptions and public policies.

Prominent among them are those involved in climate change research and energy policy. In recent years, they have adjusted data to fit the dangerous manmade climate chaos narrative, while doling out billions of taxpayer dollars for research that supports this perspective, and basing dire predictions and policy demands primarily on climate models that assume carbon dioxide now drives climate and weather (and the sun, water vapor, ocean currents and other powerful natural forces have been relegated to minor roles).

Reform is essential. Meanwhile, another troubling example underscores the scope of the problem and the difficulties Congress and other government administrators face when they try to rein in rogue agencies.. ...."

Are you denying Mann's Hockey Stick?

Nope, but it was an historical reconstruction published nearly twenty years ago., it made no projections, certainly not covering the period of the pause.

Still waiting for evidence to back up the accusations, but not holding my breath.

Entropic man:

As I said, my comment was simplified. There are devils in the detail and other feedbacks which make things more complex. Irrigation would indeed increase local humidity, and have some extra warming effect.

Some extra warming effect? The direct effects from increased water vapor due a.o. irrigation should dwarf any indirect effect from CO2.
The indirect increase in vapor via CO2 has been at most 1/3 of 4% (as you say, others have it a bit higher) or 1.33%. Yet increases due to (a.o.) irrigation are usually much higher (>10% averaged over a year).

[http://sdsu-dspace.calstate.edu/bitstream/handle/10211.10/1719/Perkins_Emily.pdf;sequence=1]
Perkins, 2011, IRRIGATION CONTROLS ON ATMOSPHERIC WATER VAPOR, SOUTHERN INDIA

Irrigation altered basin-wide ET in several large basins, including the Colorado River Basin [Haddeland et al.,
2 2006], the Krishna Basin in southern India [Biggs et al., 2008], and the Amu and Syr Darya basins in central Asia [Shibuo et al., 2007].
...
Water vapor measurements rarely extend into the atmosphere leading research to focus on surface data or atmospheric models to estimate the net impacts of irrigation [de Rosnay et al., 2003; Douglas et al., 2006; Lee et al., 2008; Lohar and Pal, 1995]. Several models have estimated water vapor over India. Douglas et al. [2006] used a bottom up approach and estimated that ET in India increased by 55% in the dry season from a preagricultural to a modern landscape [Douglas et al., 2006].

https://wattsupwiththat.com/2015/10/24/water-vapour-the-big-wet-elephant-in-the-room/
Ball, 2015, Water Vapour: The Big Wet Elephant In The Room

Figure 1 shows the current percentages of greenhouse gases as a part of total atmospheric gases. The challenge for the IPCC and its promoters was to create a different set of percentages and images for the public. This required amplifying one side, as I explained about CO2 and CH4 while downplaying the other side.
[4% of GHG is CO2, 95% of GHG is H2O]
...
The level of knowledge is the same in the 2013 AR5 Report (Figure 3). The changes are telling. Now “Long-lived greenhouse gasses” are “Well-mixed greenhouse gasses.” This is because they switched the narrative. The early story said that CO2 residency time was 100 years, but that was challenged and corrected. The new, false, narrative was that CO2 was well mixed. The “Very High” assessment doesn’t fit the increasing divergence between the CO2 level and the temperature.
...
You can only determine the CO2 effect if you know the effect of the predominant greenhouse gas – water vapor.

The IPCC acknowledges that water vapor is the most important and abundant greenhouse gas. In the 2007 Report they wrote

"Water vapour is the most abundant and important greenhouse gas in the atmosphere."

They then explain why they are going to ignore it.

"However, human activities have only a small direct influence on the amount of atmospheric water vapour."

The 2013 IPCC Report FAQ 8.1 responds to criticism about not including water vapour as a greenhouse. Here is the entire FAQ, which is illuminating and begs many questions.

"...
Additional water vapour is injected into the atmosphere from anthropogenic activities, mostly through increased evaporation from irrigated crops, but also through power plant cooling, and marginally through the combustion of fossil fuel. One may therefore question why there is so much focus on CO2, and not on water vapour, as a forcing to climate change.
..."
...
Their argument misses the point entirely. They don’t know how much contribution human water vapour (H2O) makes because they don’t have critical information. They don’t know how much H2O humans produce, how much H2O there is in the atmosphere, or the amount H2O varies naturally. When assessing how much the energy balance is affected by greenhouse gases, the source is only an issue if you want to point an accusatory political finger. For science, the total amount of each gas and how it varies is critical.
...
Water vapour is the giant wet elephant in the IPCC laboratory. The definition of climate change they received allowed them to ignore anything that didn’t fit their hypothesis. As a result, the IPCC focus is on eliminating, ignoring, and creating false narratives to enhance the role of CO2. This has the effect of pushing the elephant of water vapour under water so that like an iceberg the public only see about 10 percent of the mass.

Some numbers as to how gigantic water use is follow below.

[http://www.sjsu.edu/faculty/watkins/watervapor01.htm]

The magnitude of the water that goes into the sky from irrigation and landscaping is enormous. The Colorado River which used to flow into the Gulf of California but is now so diminished that it disappears into the desert carries more gallons of water than all the gallons of gasoline consumed throughout the U.S. An average annual flow rate for the Colorado River upstream is about 10,000 cubic feet per second. That translates into 864 million cubic feet per day, which is about 6.5 billion gallons per day. The total gasoline usage in the U.S. amounts to 378 million gallons per day, only about 6 percent of the disappearance of water from the Colorado.
...
The Burning of Fuel Oil
The total distillate fuel oil used in the U.S. in 2007 was 64.3 billion gallons, which amounts to 176.2 million gallons per day.
...
Thus the burning of 176.2 million gallons of fuel oil per day produces the water vapor in 200.9 million gallons of water.
...
Withdrawals from Acquifers
This is 6.8 trillion gallons per year or about 19 billion gallons per day. This is roughly three times the disappearance of the Colorado River.
...
The U.S. Environmental Protection Agency (EPA) estimates that Americans use 7 billion gallons of water per day for watering lawns and landscapes. There is a comparable though smaller amount used for washing cars, maintaining swimming pools and so forth. The total is thus about 12 billion gallons per day. The EPA notes that about half of this goes into evaporation. The rest gets into the plants and most of this is transpired into the air.

Irrigation
The U.S. Geological Survey (USGS) estimates that in the year 2000 water withdrawals for irrigation were 137 billion gallons per day. Irrigation withdrawals were 40 percent of total freshwater withdrawals of 342.5 billion gallons per day. Of that 342.5 billion gallons, 134.5 billion gallons were for thermo-electric power plants. Of the non-power plant usage of 208 billion gallons per day, 65 percent, was for irrigation. Note that irrigation and power plants use a nearly equal amount of water.
...
A water molecule does not stay in the atmosphere as long as a carbon dioxide molecule does. However what matters is the amount that is in the atmosphere at any one time. However one effect of anthropogenic water vapor is an increase in precipitation downwind from the regions adding water vapor to the air.
...
The overwhelming conclusion from the above is that there is no reason to neglect the direct anthropogenic increases in the atmosphere on climate. There are water vapor feedback effects induced by both the anthropogenic carbon dioxide but additionally and perhaps more importantly there are direct increases in the water vapor in the atmosphere from irrigation, landscape watering, and the burning of hydrocarbon fuels.

Around the world there is a crisis on river use. When the upstream users draw more water there is less for the downstream users. Where does the water go that is drawn from the rivers by the upstream users. That which does not find its way back to the rivers goes into the sky. Where did 90 percent of the water in the Aral Sea go. Some went into the melons and cotton grown by irrigation, but most of it went into the sky.

Radical Rodent:

JayJay: the only “greenhouse effect” you will ever be able to observe is on a night where the water in the atmosphere has condensed, giving an opaque layer at some height above the ground. This layer will reduce the effectiveness of energy radiation to space, thus cloudy nights tend to be warmer than clear nights.
There is no other demonstration of “greenhouse effect” that I can think of. Of course, should you know of one, please let us all know.

RR: how big the actual overall greenhouse effect is mostly irrelevant. What matters is what is the major cause. IMHO the major cause (for any greenhouse effect, no matter how large or small) can only be water vapor, via the direct route, and not CO2.

Also note that controlling H2O is more a matter of population control, which is needed in many southern countries anyway.

Still waiting for evidence to back up the accusations, but not holding my breath.

Mar 6, 2018 at 9:59 AM | Phil Clarke

Mann has produced no evidence to explain how he vanished the MWP and LIA, so now you are trying to disown the Hockey Stick.

If only Climate Science had developed some honesty 20 years ago, billions could have been saved.

Is it now the Consensus position in Climate Science, that the Hockey Stick should be jettisoned?