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Pmt111500

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Science basics-thread?
« on: July 04, 2019, 08:31:19 AM »
As the forum has grown to a quite large place, it might be useful to have a science basics thread. Kind of 'RTFM' or 'FAQ' of old. Sure, there are some details to be discussed in most scientific issues like the one with the band broadening questioned by Gerlich & Tschesuner some years back which was properly refuted by better men than me. But surely, there are some common questions and misunderstanindings that take up a whole lotta space elsewhere.

Like a list of simple facts like the one I recently had to check, methane is indeed lighter than air and thus accumulates to TOA in the tropics where massive sprite lightning may destroy some of it...

Or the one I messed up with the MJO confusing the segments on the standard plot.

Like some regular absorption diagrams for common gases. Or a list of heats of fusion and vaporization and the associated temperatutes.

Well, maybe this is a stupid idea, referring to skeptical science is likely always a good choice. But still, should there f.e. be some basic explanation of entropy, blackbody radiation, entalphy, well energy diagrams of chemical reactions and such on a site that mainly deals with ice on natural environments and social cost of carbon (for a lack of a better phrase)? Once there'd be enough info the thread should be locked down.

pietkuip

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Re: Science basics-thread?
« Reply #1 on: July 04, 2019, 10:50:53 AM »
Probably, a wiki would be a much more suitable structure for that.

Pmt111500

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Re: Science basics-thread?
« Reply #2 on: July 04, 2019, 11:16:59 AM »
Probably, a wiki would be a much more suitable structure for that.

Yes, cross-linking several science-articles in a way relevant to climate science would probably be best. There's of course
Spencer Weart's Discovery of GW which does this to some extent, he though left the 'anthropogenic' bit out of the header.
https://history.aip.org/climate/index.htm


kassy

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Re: Science basics-thread?
« Reply #3 on: July 05, 2019, 02:39:34 PM »
That is a great resource. Back then i really appreciated his explanation of the simple old single column models.

It would be cool if he could do an addendum on more recent model developments and also paleo stuff (all ask him what it costs as soon as i win the lottery).

Not sure how useful a basic science thread is because there about as many levels of basic as there are people.

I suggest just taking the questions as and when they come. Mostly they should pop up in a specific context and might be best answered there (unless they are the threads we would like clutterfree).

I recently reposted Water Vapour Feedback or Forcing? from RealClimate which also has good basic stuff (and more) ... did not think i would repost that 2005 golden oldie but it was still useful.

I think it works in reverse. If the basic questions pop up they will be answered (and as we saw recently then it really depends on what the person asking the question does with the first two links).

Really simple stuff would be just duplicating wikipedia anyway and we can just link that. 



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Tor Bejnar

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Re: Science basics-thread?
« Reply #4 on: December 02, 2019, 04:39:54 AM »
Seems like a good place for this:

A Review of Bob Henson’s Awesome Book: The Thinking Person’s Guide to Climate Change
by Weather Underground's Jeff Masters - 2019 Nov. 27
Quote
This is the fifth version of Bob’s comprehensive climate change book, which originally appeared as the "Rough Guide to Climate Change" back in 2006 (see my 2008 review). He organizes the new book into five sections:

The basics--global warming in a nutshell
The symptoms--what's happening now, and what might happen in the future
The science--how we know what we know about climate change
Debates & solutions--from spats and spin to saving the planet
What can you do?--reducing your footprint and working for action
...
Much more at the WU link.
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

gerontocrat

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Re: Science basics-thread?
« Reply #5 on: December 02, 2019, 02:27:05 PM »
I have a folder called basic data and arithmetic. There I keep stuff such as
- the data and arithmetic to show how the oceans as a heat sink have a capacity more than 1,000 times that of the atmosphere,
- conversion tables (e.g.s energy as Kwh, BTU, CO2 as ppm & GT),
- area of land & oceans at various levels of detail,
- basic physics (e.g. explanation of how a greenhouse gas heats up the atmosphere)

I only store in that folder that which will not change. Climate science is changing so fast that as soon as a conventional wisdom is established it gets demolished. Read recent(ish) posts by AbruptSLR how the ECS values in the new CMIP6 models are so much higher than those used in the CMIP5 cycle.

I can see this thread as a useful place to put basic data, but not for where there is still debate on AGW - how much, when, what and where - i.e. almost everything.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

blumenkraft

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Re: Science basics-thread?
« Reply #6 on: December 30, 2019, 08:54:19 AM »
Yosemite Nature Notes - 9 - Frazil Ice


TerryM

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Re: Science basics-thread?
« Reply #7 on: January 14, 2020, 12:51:40 AM »
As far as basic science leading to better technology let me link back to morganism's post at
https://forum.arctic-sea-ice.net/index.php/topic,480.msg244268.html#msg244268


What is announce are new synthetic clathrates that can be Semiconductors or/and Superconductors at high temperatures!


DARPA and the DOE appear to have this covered, but this was no Manhattan project & I assume the world is already hard at work on this.


If it's real (and there is no reason to suspect that it isn't) it canwill change everything we thought we knew of the limits of electronic devices from solar cells, to computers, to batteries, to ???????.


It's as if transistors were new on the world stage.
A Gigantic Black Swan has touched down.


Before Clathrates / After Clathrates


It's that big - I think.
Terry


nanning

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Re: Science basics-thread?
« Reply #8 on: January 14, 2020, 06:33:15 AM »
^^
[joking]
Here is the solution to carbon sequestration: turn it into diamond.
[/joking]
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
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Aporia_filia

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Re: Science basics-thread?
« Reply #9 on: January 15, 2020, 01:35:32 PM »
I don't know if this is the right thread for this web, happy to move it somewhere else.

NASA free software. More than 600 programs for very different subjects. Have a look!

https://software.nasa.gov/

nanning

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Re: Science basics-thread?
« Reply #10 on: January 15, 2020, 06:11:10 PM »
Nice find Aporia.

This might be of interest:

Viewpoints: Software for Visualization of Multivariate Data
A software application that allows the interactive visualization of multivariate data using a variety of standard techniques, Viewpoints can be used with extremely large data sets.
Open Source
http://www.assembla.com/wiki/show/viewpoints/downloads
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

gerontocrat

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Re: Science basics-thread?
« Reply #11 on: January 23, 2020, 09:58:58 PM »
Global Warming Potential of greenhouse gases- basic data

https://en.wikipedia.org/wiki/Global_warming_potential
Quote
Global warming potential (GWP) is a measure of how much heat a greenhouse gas traps in the atmosphere up to a specific time horizon, relative to carbon dioxide. It compares the amount of heat trapped by a certain mass of the gas in question to the amount of heat trapped by a similar mass of carbon dioxide and is expressed as a factor of carbon dioxide (whose GWP is standardized to 1).

A GWP is calculated over a specific time horizon, commonly 20, 100, or 500 years. User related choices such as the time horizon can greatly affect the numerical values obtained for carbon dioxide equivalents. In the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, methane has a lifetime of 12.4 years and with climate-carbon feedbacks a global warming potential of 86 over 20 years and 34 over 100 years in response to emissions. For a change in time horizon from 20 to 100 years, the GWP for methane therefore decreases by a factor of approximately 2.5.[1]

The GWP depends on the following factors:

- the absorption of infrared radiation by a given species
- the spectral location of its absorbing wavelengths
- the atmospheric lifetime of the species.

Thus, a high GWP correlates with a large infrared absorption and a long atmospheric lifetime. The dependence of GWP on the wavelength of absorption is more complicated. Even if a gas absorbs radiation efficiently at a certain wavelength, this may not affect its GWP much if the atmosphere already absorbs most radiation at that wavelength. A gas has the most effect if it absorbs in a "window" of wavelengths where the atmosphere is fairly transparent. The dependence of GWP as a function of wavelength has been found empirically and published as a graph.[2]

Because the GWP of a greenhouse gas depends directly on its infrared spectrum, the use of infrared spectroscopy to study greenhouse gases is centrally important in the effort to understand the impact of human activities on global climate change.

The substances subject to restrictions under the Kyoto protocol are either rapidly increasing their concentrations in Earth's atmosphere or have a large GWP.

I attach a table of GWP data. You should note the life and GWP of these gases are somewhat of a matter for debate
Here is a link to a 2016 article with a more comprehensive table of greenhouse gases.

https://www.ghgprotocol.org/sites/default/files/ghgp/Global-Warming-Potential-Values%20%28Feb%2016%202016%29_1.pdf
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"Damn, I wanted to see what happened next" (Epitaph)

nanning

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Re: Science basics-thread?
« Reply #12 on: January 24, 2020, 07:43:33 AM »
Thanks gerontocrat.
It should be easy I think to add a column with the per-ghg CO2e figures if their atmospheric fractions are known.
For Stephan's CO2e reporting, I suggest using two factors: 30 and 90 for methane CO2e, or use above table.

As a sidenote, I don't understand methane atmospheric "lifetime". I had expected a half-life time, the duration after a methane burst until 50% is changed into other molecules.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

blumenkraft

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Re: Science basics-thread?
« Reply #13 on: April 13, 2020, 09:14:46 PM »
The Debunking Handbook

Free download >> https://skepticalscience.com/docs/Debunking_Handbook.pdf

blumenkraft

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Re: Science basics-thread?
« Reply #14 on: June 09, 2020, 08:27:46 PM »
Connected Papers: A visual tool for researchers to find and explore academic papers

Link >> https://www.connectedpapers.com/

pikaia

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Re: Science basics-thread?
« Reply #15 on: June 09, 2020, 11:27:34 PM »
As a sidenote, I don't understand methane atmospheric "lifetime". I had expected a half-life time, the duration after a methane burst until 50% is changed into other molecules.
My understanding is that methane decomposes by reacting with the hydroxyl radical (OH), and the rate of decomposition is proportional to the concentration of OH. So the concentration declines at a constant rate rather than exponentially. If OH increases then the lifetime of methane will decrease.

nanning

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Re: Science basics-thread?
« Reply #16 on: June 10, 2020, 05:55:34 AM »
Thanks pikaia, that seems a large part (or all) of the explanation.
So now there's another variable of influence on GHG radiative forcing: OH. I have not read statistics about that molecule.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

kassy

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Re: Science basics-thread?
« Reply #17 on: June 10, 2020, 01:37:01 PM »
It is constantly made and destroyed.

The hydroxyl radical is often referred to as the "detergent" of the troposphere because it reacts with many pollutants, decomposing them through "cracking", often acting as the first step to their removal. It also has an important role in eliminating some greenhouse gases like methane and ozone.[3] The rate of reaction with the hydroxyl radical often determines how long many pollutants last in the atmosphere, if they do not undergo photolysis or are rained out.

https://en.wikipedia.org/wiki/Hydroxyl_radical


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blumenkraft

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Re: Science basics-thread?
« Reply #18 on: June 17, 2020, 01:39:21 PM »
A team of researchers has provided the first-ever direct evidence that extensive coal burning in Siberia is a cause of the Permo-Triassic Extinction, the Earth’s most severe extinction event.

Coal-burning in Siberia led to climate change 250 million years ago

Link >> https://asunow.asu.edu/20200615-coal-burning-siberia-led-climate-change-250-million-years-ago

Rod

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Re: Science basics-thread?
« Reply #19 on: July 17, 2020, 02:43:17 AM »
I have no idea where this should be posted.  This seemed like a possible spot.

Zack is giving a talk tomorrow on climate and atmospheric science in conjunction with the Colorado State University School of Global Sustainability.

I don’t know if he will get into what is currently happening in the Arctic, but I’m sure it will be an educational program. It starts at 3:30 pm Colorado time. That would be 5:30 pm New York time and 10:30 pm London time (I think).

I plan on listening to what he has to say. Zack is a great speaker and there is always something to be learned from his talks. 

Details are below in the screenshots from the twitter announcements.

blumenkraft

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Re: Science basics-thread?
« Reply #20 on: July 17, 2020, 10:32:28 AM »

gerontocrat

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Re: Science basics-thread?
« Reply #21 on: July 17, 2020, 02:24:53 PM »
SHH! Sustainability Happy Hour with Dr. Zack Labe

So Zack got his Ph.D thesis accepted and is a Doc. There's a man who deserved it.

Have we sent congratulations? (because we should)
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

blumenkraft

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Re: Science basics-thread?
« Reply #22 on: July 17, 2020, 02:27:56 PM »
10:30 pm London time (I think).

Yeah, we call that 22:30 in Europe... :P ;)

Have we sent congratulations? (because we should)

If you do, please send kind regards. :)

GoSouthYoungins

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Re: Science basics-thread?
« Reply #23 on: July 17, 2020, 07:21:02 PM »
I think we should consider that "science-basics" are actually perpetuation systemic racism.
big time oops

kassy

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Re: Science basics-thread?
« Reply #24 on: July 17, 2020, 07:45:32 PM »
Perpetual systemic discrimination. We want the measures to be meaningful.
But time zones are boring.
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GoSouthYoungins

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Re: Science basics-thread?
« Reply #25 on: July 17, 2020, 07:51:53 PM »
Perpetual systemic discrimination. We want the measures to be meaningful.
But time zones are boring.

They might be boring to you. But have you ever bothered to think of who established "time zones"?

Also, time itself is racist.

If time had a race, it would be white. White people own time.” Brittney Cooper
big time oops

kassy

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Re: Science basics-thread?
« Reply #26 on: July 17, 2020, 08:05:52 PM »
Time exists without perception. Who is the boss over the schedule is a different matter.

Quote
I think we should consider that "science-basics" are actually perpetuation systemic racism.
Could be a good thread in The Rest.
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Aporia_filia

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Re: Science basics-thread?
« Reply #27 on: August 14, 2020, 11:05:53 AM »
A good old sailing mate has sent me this book that could help clarifying basic knowledge about oceans (currents, tides...) Some chapters may need un update, but not the basic science.

Introduction To Physical Oceanography Robert H. Stewart Department of Oceanography Texas A & M University   Copyright 1997–2000

Understanding that can be shared since 2000, and thinking that sharing knowledge CANNOT be wrong:


ContentsPrefacevii1AVoyageofDiscovery1
1.1PhysicsoftheOcean.........................1
1.2Goals.................................2
1.3Organization.............................3
1.4TheBigPicture............................3
1.5FurtherReading...........................4
2TheHistoricalSetting7
2.1Definitions...............................7
2.2ErasofOceanographicExploration.................8
2.3MilestonesintheUnderstandingoftheOcean...........11
2.4EvolutionofsomeTheoreticalIdeas................15
2.5TheRoleofObservationsinOceanography............16
2.6SelectingOceanicDataSets.....................16
2.7DesignofOceanographicExperiments...............17
2.8Accuracy,Precision,andLinearity.................17
2.9ImportantConcepts.........................19
3ThePhysicalSetting21
3.1OceansandSeas...........................22
3.2DimensionsoftheOceans......................24
3.3BathymetricFeatures........................25
3.4MeasuringtheDepthoftheOcean.................28
3.5BathymetricChartsandDataSets.................34
3.6SoundintheOcean.........................35
3.7ImportantConcepts.........................38
4AtmosphericInfluences39
4.1TheEarthinSpace..........................39
4.2AtmosphericWindSystems.....................40
4.3ThePlanetaryBoundaryLayer...................41
4.4MeasurementofWind........................42
4.5TheSamplingProbleminScatterometry..............49
4.6WindStress..............................49
4.7ImportantConcepts.........................51
5TheOceanicHeatBudget53
5.1TheOceanicHeatBudget......................53
5.2Heat-BBudgetTerms..........................55
5.3DirectCalculationofFluxes.....................59
5.4IndirectCalculationofFluxes:BulkFormulas...........61
5.5GlobalDataSetsforFluxes.....................64
5.6GeographicDistributionofTerms..................68
5.7MeridionalHeatTransport.....................71
5.8MeridionalFreshWaterTransport.................73
5.9VariationsinSolarConstant.....................75
5.10ImportantConcepts.........................75
6Temperature,Salinity,andDensity77
6.1DefinitionofSalinity.........................77
6.2DefinitionofTemperature......................81
6.3GeographicalDistribution......................83
6.4TheOceanicMixedLayer......................86
6.5PotentialTemperature........................86
6.6MeasurementofTemperature....................92
6.7MeasurementofConductivity....................96
6.8MeasurementofPressure......................98
6.9TemparatureandSalinityWithDepth...............99
6.10MeasurementsofMixed-LayerDepth................101
6.11Lightintheoceanandabsorptionoflight.............101
6.12ImportantConcepts.........................105
7TheEquationsofMotion107
7.1DominantForcesforOceanDynamics...............107
7.2CoordinateSystem..........................108
7.3TypesofFlowintheocean.....................109
7.4ConservationofMassandSalt...................110
7.5TheTotalDerivative(D/Dt)....................111
7.6MomentumEquation.........................113
7.7ConservationofMass:TheContinuityEquation.........116
7.8CalculationofVerticalVelocityUsingContinuity.........118
7.9SolutionstotheEquationsofMotion................119
7.10ImportantConcepts.........................120

8EquationsofMotionWithViscosity121
8.1TheInfluenceofViscosity......................121
8.2Turbulence..............................122
8.3CalculationofReynoldsStress:...................125
8.4Stability................................129
8.5MixingintheOcean.........................134
8.6ImportantConcepts.........................138
9ResponseoftheUpperOceantoWinds139
9.1InertialMotion............................139
9.2EkmanLayerattheSeaSurface..................142
9.3EkmanMassTransports.......................150
9.4ApplicationofEkmanTheory....................152
9.5ImportantConcepts.........................154
10GeostrophicCurrents157
10.1HydrostaticEquilibrium.......................157
10.2GeostrophicEquations........................159
10.3SurfaceGeostrophicCurrentsFromAltimetry...........160
10.4GeostrophicCurrentsFromHydrography.............164
10.5AnExampleUsingHydrographicData...............170
10.6CommentsonGeostrophicCurrents................172
10.7CurrentsFromHydrographicSections...............177
10.8LagrangeanMeasurementsofCurrents...............180
10.9EulerianMeasurementsofCurrents.................187
10.10ImportantConcepts.........................190
11WindDrivenOceanCirculation191
11.1Sverdrup’sTheoryoftheOceanicCirculation...........191
11.2WesternBoundaryCurrents.....................197
11.3Munk’sSolution...........................198
11.4ObservedCirculationintheAtlantic................201
11.5ImportantConcepts.........................206
12VorticityintheOcean209
12.1DefinitionsofVorticity........................209
12.2ConservationofVorticity......................212
12.3VorticityandEkmanPumping...................215
12.4ImportantConcepts.........................220
13DeepCirculationintheOcean221
13.1ImportanceoftheThermohalineCirculation............222
13.2TheoryfortheThermohalineCirculation.............227
13.3ObservationsoftheDeepCirculation................231
13.4AntarcticCircumpolarCurrent...................237
13.5ImportantConcepts.........................240
14EquatorialProcesses243
14.1EquatorialProcesses.........................244
14.2ElNi˜no................................248
14.3ElNi¨noTeleconnections.......................257
14.4ObservingElNi˜no..........................258
14.5ForecastingElNi˜no.........................260
14.6ImportantConcepts.........................262
15NumericalModels26515.1Introduction-SomeWordsofCaution................265
15.2NumericalModelsinOceanography................267
15.3SimulationModels..........................268
15.4Primitive-EquationModels.....................268
15.5CoastalModels............................272
15.6AssimilationModels.........................276
15.7CoupledOceanandAtmosphereModels..............279
15.8ImportantConcepts.........................282
16OceanWaves283
16.1LinearTheoryofOceanSurfaceWaves...............283
16.2Nonlinearwaves...........................288
16.3WavesandtheConceptofaWaveSpectrum...........289
16.4Ocean-WaveSpectra.........................295
16.5WaveForecasting...........................300
16.6MeasurementofWaves........................301
16.7ImportantConcepts.........................304
17CoastalProcessesandTides305
17.1ShoalingWavesandCoastalProcesses...............305
17.2Tsunamis...............................309
17.3StormSurges.............................312
17.4TheoryofOceanTides........................313
17.5TidalPrediction...........................319
17.6ImportantConcepts.........................324
References327


kassy

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Re: Science basics-thread?
« Reply #28 on: August 14, 2020, 06:36:46 PM »
Thanks! I have been wanting something like this for ages.
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Tom_Mazanec

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Re: Science basics-thread?
« Reply #29 on: August 17, 2020, 04:20:16 PM »
Quote
Northern peatlands have accumulated large stocks of organic
carbon (C) and nitrogen (N), but their spatial distribution and
vulnerability to climate warming remain uncertain. Here, we used
machine-learning techniques with extensive peat core data (n >
7,000) to create observation-based maps of northern peatland C
and N stocks, and to assess their response to warming and permafrost thaw. We estimate that northern peatlands cover 3.7 ± 0.5
million km2 and store 415 ± 150 Pg C and 10 ± 7 Pg N. Nearly half
of the peatland area and peat C stocks are permafrost affected.
Using modeled global warming stabilization scenarios (from 1.5 to
6 °C warming), we project that the current sink of atmospheric C
(0.10 ± 0.02 Pg C·y−1
) in northern peatlands will shift to a C source
as 0.8 to 1.9 million km2 of permafrost-affected peatlands thaw.
The projected thaw would cause peatland greenhouse gas emissions equal to ∼1% of anthropogenic radiative forcing in this century. The main forcing is from methane emissions (0.7 to 3 Pg
cumulative CH4-C) with smaller carbon dioxide forcing (1 to 2 Pg
CO2-C) and minor nitrous oxide losses. We project that initial CO2-C
losses reverse after ∼200 y, as warming strengthens peatland
C-sinks. We project substantial, but highly uncertain, additional
losses of peat into fluvial systems of 10 to 30 Pg C and 0.4 to 0.9
Pg N. The combined gaseous and fluvial peatland C loss estimated
here adds 30 to 50% onto previous estimates of permafrost-thaw
C losses, with southern permafrost regions being the most
vulnerable.
I'm surprised the magnitude is as low as 1%, kassy.

kassy

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Re: Science basics-thread?
« Reply #30 on: August 17, 2020, 04:44:51 PM »
Why? What does the measure say?
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Tom_Mazanec

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Re: Science basics-thread?
« Reply #31 on: August 17, 2020, 09:16:44 PM »
The thaw would cause 1% of the Anthropogenic GHG emissions for this century the abstract says.

gerontocrat

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Re: Science basics-thread?
« Reply #32 on: August 31, 2020, 01:34:33 PM »
When looking for something else I found this.

I was... stunned. I mean - bacteria 15% of the total biomass of life on earth.

https://www.pnas.org/content/115/25/6506
The biomass distribution on Earth

Quote
Significance
The composition of the biosphere is a fundamental question in biology, yet a global quantitative account of the biomass of each taxon is still lacking. We assemble a census of the biomass of all kingdoms of life. This analysis provides a holistic view of the composition of the biosphere and allows us to observe broad patterns over taxonomic categories, geographic locations, and trophic modes

Results
The Biomass Distribution of the Biosphere by Kingdom.

In Fig. 1 and Table 1, we report our best estimates for the biomass of each taxon analyzed. We use biomass as a measure of abundance, which allows us to compare taxa whose members are of very different sizes. Biomass is also a useful metric for quantifying stocks of elements sequestered in living organisms. We report biomass using the mass of carbon, as this measure is independent of water content and has been used extensively in the literature.


Fig. 1.
Graphical representation of the global biomass distribution by taxa. (A) Absolute biomasses of different taxa are represented using a Voronoi diagram, with the area of each cell being proportional to that taxa global biomass (the specific shape of each polygon carries no meaning).


The sum of the biomass across all taxa on Earth is ≈550 Gt C, of which ≈80% (≈450 Gt C; SI Appendix, Table S2) are plants, dominated by land plants (embryophytes). The second major biomass component is bacteria (≈70 Gt C; SI Appendix, Tables S3–S7), constituting ≈15% of the global biomass.

Other groups, in descending order, are fungi, archaea, protists, animals, and viruses, which together account for the remaining <10%. Despite the large uncertainty associated with the total biomass of bacteria, we estimate that plants are the dominant kingdom in terms of biomass at an ≈90% probability (more details are provided in the SI Appendix).

Aboveground biomass (≈320 Gt C) represents ≈60% of global biomass, with belowground biomass composed mainly of plant roots (≈130 Gt C) and microbes residing in the soil and deep subsurface (≈100 Gt C). Plant biomass includes ≈70% stems and tree trunks, which are mostly woody, and thus relatively metabolically inert.

Bacteria include about 90% deep subsurface biomass (mostly in aquifers and below the seafloor), which have very slow metabolic activity and associated turnover times of several months to thousands of years (18⇓⇓⇓–22). Excluding these contributions, global biomass is still dominated by plants (SI Appendix, Fig. S1), mostly consisting of ≈150 Gt C of plant roots and leaves and ≈9 Gt C of terrestrial and marine bacteria whose contribution is on par with the ≈12 Gt C of fungi (SI Appendix, Table S8).

Whereas groups like insects dominate in terms of species richness [with about 1 million described species (23)], their relative biomass fraction is miniscule. Some species contribute much more than entire families or even classes. For example, the Antarctic krill species Euphausia superba contributes ≈0.05 Gt C to global biomass (24), similar to other prominent species such as humans or cows. This value is comparable to the contribution from termites (25), which contain many species, and far surpasses the biomass of entire vertebrate classes such as birds. In this way, the picture that arises from taking a biomass perspective of the biosphere complements the focus on species richness that is commonly held (SI Appendix, Fig. S3).


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kassy

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Re: Science basics-thread?
« Reply #33 on: August 31, 2020, 07:25:25 PM »
Nice graphic. As in clarity not what it shows per se.
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nanning

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Re: Science basics-thread?
« Reply #34 on: September 01, 2020, 07:17:56 AM »
Thank you for that gerontocrat.
Hadn't seen it before in such a great visual representation.
Staggering these ratio's, and humbling.
Adding evolutionary age (success) will be even more humbling.
The human eye versus the scientific eye.
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Why do you keep accumulating stuff?