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Extinction Rebellion are threatening to shut down Heathrow Airport with drones

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Extinction Rebellion are threatening to shut down Heathrow Airport with drones

Old 12th Jun 2019, 06:53
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Dear Moderator
please can we park this climate change thread in a more appropriate forum
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Old 12th Jun 2019, 14:17
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Originally Posted by cwatters
As I understand it CO2 is such a good absorber of IR that (even at pre industrialisation levels of C02) it only takes about 25 meters of the atmosphere to scatter most of the IR radiated by the earth (http://clivebest.com/blog/?p=1169 ). This means energy is only radiated into space from high up in the atmosphere, where the air and CO2 is thin enough.

Its been suggested that adding CO2 raises the effective height from which IR energy is radiated. Unfortunately the higher you go the colder it gets and IR radiation is proportional to the fourth power of temperature (T^4).

If less energy is radiated into space the temperature of the planet must increase until the energy lost from the earth once again matches that arriving from the sun.
Except that most energy radiated is carried past this theoretical effective height by convection. A significantly long way as those who have flown through the Intertropical convergence zone will attest - these are the convective Hadley cells at the equator. Even the tops of Cb in cold fronts in the temperate zone are well above the 'effective height' and these are the Ferrel cells. As the water in these clouds first condense and then freeze heat is released a long way above the altitudes at which CO2 is an issue,
You should also remember that the absorption of infrared by CO2 is logarithmic so each doubling of CO2 has half the effect of the previous. At 400ppm the absorption in the 3 narrow IR wavelength bands are almost saturated. Two of the bands are in any case overlapping with water vapor absorption.

Note:
* There is no correlation between CO2 and atmospheric temperature at geologic timescales where CO2 has been tens to hundred times higher concentrations in the atmosphere. The brief 20 year correlation in the last decades of the 20th century do not imply causation. See this spurious correlation


NONE of the forecasts made by climate scientists' models have been correct. Normally in science if the forecast made based on your hypothesis is falsified n the real world the hypothesis is abandoned.
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Old 12th Jun 2019, 15:05
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Note
:
* There is no correlation between CO2 and atmospheric temperature at geologic timescales where CO2 has been tens to hundred times higher concentrations in the atmosphere.
https://www.ncdc.noaa.gov/global-war...erature-change


Temperature change (light blue) and carbon dioxide change (dark blue) measured from the EPICA Dome C ice core in Antarctica (Jouzel et al. 2007; Lüthi et al. 2008).

and yes there are times when temperature changes lead C02 changes. You can find an explanation for that here. https://skepticalscience.com/co2-lags-temperature.htm
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Old 12th Jun 2019, 15:48
  #124 (permalink)  
 
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Originally Posted by cwatters

Temperature change (light blue) and carbon dioxide change (dark blue)
I have some understanding of how the historical CO2 levels can be inferred from ice cores.
But can you explain the method or basis for inferring historical temperatures?

We're not using one as the basis for the other are we?
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Old 12th Jun 2019, 18:21
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Originally Posted by WingNut60
I have some understanding of how the historical CO2 levels can be inferred from ice cores.
But can you explain the method or basis for inferring historical temperatures?
https://www.scientificamerican.com/a...-temperatures/

The measurement of the gas composition is direct: trapped in deep ice cores are tiny bubbles of ancient air, which we can extract and analyze using mass spectrometers.

Temperature, in contrast, is not measured directly, but is instead inferred from the isotopic composition of the water molecules released by melting the ice cores.

Continues..
In short... it takes more energy to evaporate heavier water molecules. So when it's warmer more heavy molecules are evaporated from the oceans and deposited as snow which is later compressed to ice. When it's colder fewer heavy molecules are evaporated and deposited in the snow.

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Old 12th Jun 2019, 18:52
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You seem knowledgable 73 Qanda. Correct me if I am wrong but when I did physics at school 60years ago, I`m sure I was taught that floating ice displaces its own volume in the water containing it. If that ice melts, its volume decreases thus the water level drops. This is surely true of the Arctic (floating) but not the Antarctic (on bedrock). ?
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Old 12th Jun 2019, 19:40
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Originally Posted by VFR Only Please
ii

Well, free country and all that, Out. To paraphrase Will Rogers, I just know what I read in the scientific journals.
https://blogs.agu.org/geospace/2019/...wYKb7f2ULuqVow

I think dr dre makes a good point about "people who are older and don't think they'll be affected by any real catastrophic effects of climate change when they occur." I'm 64 and have a lifetime of peace and stability behind my lucky self. Even if the chickens come home to roost tomorrow, well, I've had my life. If I were 20 I can imagine feeling pretty bitter and subversive toward Business as Usual.

In response to 73quanda -- especially given his mention of NASA -- and his plea for up-to-date sources -- here's a link from something NASA has put up that I copied, like, 30 seconds ago: https://climate.nasa.gov/evidence/

Obviously you can't hope for all scientific data to agree all the time. That's what makes science so much FUN and why its wheels turn so slowly.

I live in the Alps. When I first moved to these parts almost 40 years ago, you could go to Mont Blanc and take a cog railway up to the enormous final stage of the glacier. There's a hotel up there built in 1880 (mark that year). From there it was a short jaunt down to the ice.
NOW you go up to the same place. They have put in a freaking cable-car since the ice-level has fallen so far. But then it kept on falling, so there's an endless succession of steel steps down to what's left of the glacier. Then you have to climb back up (only the fittest survive).
All that in 40 years. And they have painted every last one of those years on the bare rock just to drive the point home.
Do I need a PhD to notice this?

Let's all remember that climate is by definition a stable Trend, and can't be upset by inherently chaotic weather events, such as a bad winter.

As for Thread Drift, if global heating weren't the biggest challenge going, probably only a small minority (with whom I might sympathize) would oppose a third runway.
But it is. So you can't separate the two issues.
Just along the Alps at Jungfrau Joch there is a climate station that has recorded no glacier at all 2000 yrs ago, so they had a warm period then, which enabled Hannibal to get his Elephants across. I don’t think they had man made global warming then, climate change yes.
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Old 12th Jun 2019, 21:22
  #128 (permalink)  
 
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Originally Posted by cwatters
[b]

https://www.ncdc.noaa.gov/global-war...erature-change


Temperature change (light blue) and carbon dioxide change (dark blue) measured from the EPICA Dome C ice core in Antarctica (Jouzel et al. 2007; Lüthi et al. 2008).

and yes there are times when temperature changes lead C02 changes. You can find an explanation for that here. https://skepticalscience.com/co2-lags-temperature.htm
The assumption being made is that CO2 is 'trapped' in bubbles in the ice. However, CO2 is extremely soluble in water as carbonic acid and will diffuse through the ice so the bubble contents are not a reliable metric. ( CO2 diffusion in polar ice ) There is also research that indicates that the bubbles may form when the cores are drilled and rapidly decompressed.

There are many temperature/CO2 graphics some that go back further and use multiple proxies such as plant stomata give a different picture, Such as:



You will note first that things have been a LOT warmer in the past and that there is a homeostasis mechanism that seems to stop any overheating. Note also that we are at the cold end of the Holocene which is an interglacial in an ice age. The Holocene optimum around 10,000 years ago, the Minoan optimum,the Roman Optimum, the Medieval Warm Period were all warmer than present and were successively colder optima.
To assist with the panic the Y axes of the published temperature graphs are wildly expanded to make even minor changes look extreme. The current temperature 'anomaly is approximately 0.35C (from UAH) which a met observer would round down to zero.
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Old 12th Jun 2019, 22:10
  #129 (permalink)  
 
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global temperature

Ian W - very interesting graph. The geocraft website is an interesting trove. I did some time in Geology before I switched to engineering.
One thing I observe about the AGW debate is the remarkable absence of geo professionals (and statisticians, another serious omission) in the discussion. As they tend to have a long term view, the ones I know tend to be quite dismissive of the climate modelers and regard the idea of humans controlling climate as rather amusing if not just plain stupid.
Climate modelers are a very very small community who approve each others papers and grants. One modeler from U of T was on Charle Rose and said there are 20 credible climate modeling groups in the world. Think about it. Each of these groups is run by , or was started by a very smart person, as they are sure to let you know. You will not work there or get funded unless you agree with the boss. That is peer reviewed science 101, sorry that is the way it works. That was very clear in the climate gate emails.
That is a very small number of people to rely on to restructure the words economy. . As I told Dr Dre, look up Barry Marshall, Noble Prize 2005, for the value of "consensus".
When the American Physical Society set up a committee, run by Dr Stephen Koonin, to look at the "incontrovertible evidence of human AGW" they invited several physicists not involved in the global warming movement to participate. When the summary did not suit the politics, the statement was was changed to something more PC.
The IPCC was set up to advise governments on how to adapt to climate change, not to make an assessment of the science. One big problem I have with the IPCC is that the section authors are reviewing their own papers. The section members are chosen by governments, ie Al Gore. There is no real question of the underlying assumptions. Most people involved are going on faith that it is a problem and the models are correct.
I can still remember when I was growing up the big thing was the next ice age. There were serious proposals to sprinkle carbon black on the ice sheets to melt them.
Y2K anyone?
20driver
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Old 13th Jun 2019, 00:37
  #130 (permalink)  
 
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Mods can we please find another location for this
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Old 13th Jun 2019, 05:19
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The Gatwick incident was illusory, a figment of someones imagination.

The 'authorities' brought in a plethora of anti-drone paraphernalia but they failed to detect anything.

The weakest link in airport operations is the use of VHF/AM communications which can be jammed with about $100 of equipment.
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Old 13th Jun 2019, 06:32
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20driver

Invoking Y2K destroys rather than supports your argument. A classic case of the Dunning-Kruger effect.


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Old 13th Jun 2019, 07:20
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Originally Posted by Ian W
NONE of the forecasts made by climate scientists' models have been correct
Source please, that's quite a statement
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Old 13th Jun 2019, 07:54
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Originally Posted by JLWSanDiego
Mods can we please find another location for this
Agree. I know we don’t have to read the thread if we don’t want to but I’m sure there are better places for this discussion rather than a forum meant for things to do with flying airplanes
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Old 13th Jun 2019, 08:32
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Originally Posted by 20driver
I did some time in Geology before I switched to engineering.
One thing I observe about the AGW debate is the remarkable absence of geo professionals (and statisticians, another serious omission) in the discussion. As they tend to have a long term view, the ones I know tend to be quite dismissive of the climate modelers and regard the idea of humans controlling climate as rather amusing if not just plain stupid.
Funny, all these worldwide geology organisations are totally disagreeing with you:

The increase of CO2 in modern times, most likely due to humans burning fossil fuels, has led to an enhanced greenhouse effect which is increasing our planet’s average temperature.
As a result sea levels are rising, partly because ocean water is expanding as it warms, and partly because polar ice is melting. Climate change is already causing ecosystems to change.
British Geological Survey

In the run up to the UN Climate Change Conference COP 21 scheduled for December 2015, 24 of the UK's foremost academic institutions, including the Geological Society, have published a joint Climate Communiqué calling on governments to take immediate action to avert the serious risks posed by climate change.
The Geological Society

The concentrations of greenhouse gases in the atmosphere are now higher than they have been for many thousands of years. Human activities (mainly greenhouse-gas emissions) are the dominant cause of the rapid warming since the middle 1900s (IPCC, 2013). If the upward trend in greenhouse-gas concentrations continues, the projected global climate change by the end of the twenty-first century will result in significant impacts on humans and other species.
The Geological Society of America

I'm just loving coming onto this thread and debunking skeptic's claims with linked information from credible scientific organisations. I agree, let's get this thread to Jet Blast so we can continue the fun.
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Old 13th Jun 2019, 08:35
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Originally Posted by Gove N.T.
better places for this discussion rather than a forum meant for things to do with flying airplanes
There is no more urgent or significant topic than this, for anyone concerned with flying airplanes.
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Old 13th Jun 2019, 08:43
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The 'authorities' brought in a plethora of anti-drone paraphernalia but they failed to detect anything.
Or was it live field test that could only be carried out under real conditions? I'm not expecting anyone to tell us.
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Old 13th Jun 2019, 10:30
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There appears to be a potential criminal threat to operations at London Heathrow Airport.

What is needed to mitigate this? Police? / Army? / GCHQ? / MI 5? / Other? Who has the
means to deal with it? Failure to deal with it will encourage even worse criminals to then
consider drone methods against.... Palace / Parliament / football stadiums / etc.

Lets concentrate on this and put aside the never ending global warming debate for now.
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Old 13th Jun 2019, 12:39
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Originally Posted by arearadar70
You seem knowledgable 73 Qanda. Correct me if I am wrong but when I did physics at school 60years ago, I`m sure I was taught that floating ice displaces its own volume in the water containing it. If that ice melts, its volume decreases thus the water level drops. This is surely true of the Arctic (floating) but not the Antarctic (on bedrock). ?
Floating ice displaces a volume of water equal to it's mass not it's volume. The mass remains constant when it melts. So yes the volume of the ice does reduce when it melts but the water level stays the same.

Aside: Most of the rise in sea level to date has been due to the water expanding due to the temperature rising rather than ice on land melting.
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Old 13th Jun 2019, 12:52
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Originally Posted by Ian W
You will note first that things have been a LOT warmer in the past and that there is a homeostasis mechanism that seems to stop any overheating.
Indeed. It appears to be limited to about 22C where as current global average temperatures are about 15C. It might also take a few million years to get to 22C. It will get there a lot sooner if we carry on the way we are.


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