What does global weirding mean regarding temperature extremes? Global weirding is a term used to describe how, with global warming, we will see more extreme weather events:

Avoid the term “global warming.” I prefer the term “global weirding,” because that is what actually happens as global temperatures rise and the climate changes. The weather gets weird. The hots are expected to get hotter, the wets wetter, the dries drier and the most violent storms more numerous.
The fact that it has snowed like crazy in Washington — while it has rained at the Winter Olympics in Canada, while Australia is having a record 13-year drought — is right in line with what every major study on climate change predicts: The weather will get weird; some areas will get more precipitation than ever; others will become drier than ever.

I have a decent understanding of physics but don't know much about weather and climate. I think I understand a few things about global weirding:

Warmer waters mean typhoons can form more often, so in locations where extreme weather is also caused by typhoons they will see this more often

Warmer air can transport more water and since steam pressure rises greater than linear with temperature, the same temp. swing around a high mean means that more water can precipitate.

I often here a statement to the effect that more energy in a weather system means it has more extreme 'swings' in its behaviour. I find this rather opaque and unconvincing.

Here's what I don't understand: Does 'extreme heat wave' in this context mean

In 2100, we'll see more extreme heat events relative to 2015 mean temperatures or

In 2100 we'll see more extreme heat events relative to 2100 mean temperatures

I think it means the latter, but given that today's heat waves can cost lives and damage crops, I think it would be relevant to point out that we will see more of this so the first definition has some merit. So I want to be clear about the terminology.
But my main question is, will we see more extreme temperature swings and what are the main mechanisms driving this?

First things first.   Global "Weirding" is very difficult to quantify.  That doesn't mean it's not happening, but it's inexact.  The idea came from climate models, which produced a lot of unexpected variations as opposed to more smooth and consistent warming and weather patterns are so complicated that there's still a lot of unknowns in this area.

  Warmer waters mean typhoons can form more often, so in locations where
  extreme weather is also caused by typhoons they will see this more
  often

Typhoons/Hurricanes are formed not just by warm water but by warm air and wind direction.   If the wind is too strong, the hurricane doesn't form, it needs to build and as it builds, begin to spin.    That's a dummies explanation, more details here

Warmer water can make hurricanes grow larger (unclear if it makes the wind blow faster too, it might).  One of the fun little jokes made about global warming is that in the IPCC's 4th assessment report (4AR) they predicted fewer hurricanes and in the 5th (5AR) they predicted more, though both were stated with some uncertainty and in the 4AR they predicted fewer with a chance of larger so those predictions aren't nearly as contradictory as this cartoon writers tries to make it sound.

I personally trust 5AR over 4AR cause it's had 7 more years of research behind it, but whatever ends up being true, predicting hurricanes is complicated.   Short article on the debate of cause of the apparent recent increase here

  Warmer air can transport more water and since steam pressure rises
  greater than linear with temperature, the same temp. swing around a
  high mean means that more water can precipitate.

I'm not sure about stream pressure, though warmer air can hold significantly more water vapor, so that I agree with.

Every 1 ° warmer, the atmosphere can hold in saturation about 6% more water.   So warmer air can hold quite significantly more water and as a result, lead to larger rain storms, though it's not just air temperature, but temperature variation as the warm air rises, etc.   But more precipitation per storm is a very likely consequence of man made climate change.   Source.

Also, while the Earth has warmed less than 1 ° C so far, most of the surface temperature over land has warmed over 1 ° C (1.53 ° C on average - see here) and it's the rainfall over land that affects us.   This means that the atmosphere over the land can hold as much as 10% more water on average than it did at pre-climate change levels.   Now, the temperature increase is lower in the upper atmosphere, so it's not really 10%.  but we've seen a few percent increase in how much water our atmosphere can store over land over just the last few decades and that's expected to continue to increase.

Water evaporation and atmospheric water-vapor replenishment is trickier and depends on a few factors, river flow rate is based on rainfall and snow-melt upstream, wind speed and plant transpiration are also important.   Some people say CO2 is plant food but it's not that simple.  Plants need to take in oxygen to capture CO2 which they use to grow.   Sunlight and soil neutralists are the actually the "food" for plants, CO2 is what they use to grow and with higher levels of CO2 in the air, they need to take in less atmosphere to get what they need and as a result, they lose less water, so less water is returned to the atmosphere from forests and trees, as CO2 increases.

So, in a nutshell, the global warmed atmosphere on average can hold more water, it can also take more time for the atmosphere "fill up again" after a rainfall or after passing over high mountains and dropping a lot of water-vapor.  That's why you get more floods and more droughts.  That much is simple physics.

If snow melt is high, that can lead to greater river flow and more flooding, and snow tends to fall in greater amounts with more water-vapor in the air.   There's a number of factors.

That strange 5 feet of snow event on Buffalo in 2014 happened when cold air blew over warm great lakes and the temperature difference caused the wind to draw a lot of water off the lakes.  Which, as it blew inland a mile or two, it quickly turned to snow and not the houses on the lake, but the houses a mile away from the lake got covered in snow.  The lake effect isn't unique to climate change.  It happened in the 1940s and 1970s, but warm lakes and a cold blast of air are the 2 drivers.  2014 was perfect for that with the polar vortex and the warm temperature colliding.  It was (I think) the largest lake effect Buffalo has on record.

Cool video here,

  I often hear a statement to the effect that more energy in a weather
  system means it has more extreme 'swings' in its behaviour. I find
  this rather opaque and unconvincing.

I think I agree with you here.  More "energy" is at best, vague, and it explains nothing.

Water vapor condensation is one way that air temperature can rapidly change.   Condensation/cloud formation releases heat so more water vapor can play a role in faster temperature change, but I'm not sure how big a factor that is.

Changes in ocean currents, perhaps caused by salinization changes and glacier melt can have significant effects.  Europe's moderate winters relative to high latitude are in large part caused by the gulf-stream and the gulf-stream may be slowing, article here.  There's still some uncertainty on the extent of this effect, but there appears to be a connection.

The Polar Vortex may also be growing as a result of climate change, based on some complicated models.   Despite the earth being warmer, harsh winters in some northern locations are still possible based on weather patterns.   Key point from article here:

  As strange as it sounds, Kim believes the intense cold air outbreaks
  in recent winters across Europe, Asia, and North America are, in his
  words, “a side effect of global warming.”

  In 2100, we'll see more extreme heat events relative to 2015 mean
  temperatures or

  In 2100 we'll see more extreme heat events relative to 2100 mean
  temperatures

This is a tough one.

First point is that there really is no 2015 mean in terms of temperature.  We can generate a global average temperature for 2015, but local temperature fluctuates too much to have a 2015 standard.   Temperature variation vs a standard is generally measured against a baseline over a few decades.   For example, see chart below.  (I couldn't get it to embed), but it compares 2014 local temperature to a baseline of 30 years, 1981-2010.

https://www.ncdc.noaa.gov/sotc/service/global/map-blended-mntp/201401.gif

If your question is rewritten as, will 2015, 2016, 2017, 2018, 2019, etc, compared to a 1981-2010 baseline have fewer extremes and look less "weird" than 2100, 2101, 2102, 2103, 2104, etc compared to a 2066-2095 baseline, then that's an interesting question but very hard to answer.   Individual years will be hit or miss, but on average, …hard to say.

As ice melt increases and as oceans continue to store heat and slowly grow warmer the weird weather variation could increase, but as CO2 levels begin to perhaps at some point, stop rising and reach a leveling off, we might see a decrease in "weirdness" compared to previous years, though the planet would still be warmer, but the rate of change might drop, so the best answer I can give you is that it could go either way.

The IPCC models suggest a gradual increase in the rate of warming for surface temperatures between now and 2100, as well as an expected increase in sea level rise but that corresponds to a steady increase in CO2.  The future CO2 growth rate could be a factor.

Guesses aside, when the experts say that weather will continue to get stranger, they are talking about compared to a consistent baseline, not a moving baseline cause that's a safer prediction, so your first sentence is the prediction that's usually put forth, but your 2nd sentence has a ballparkish 50% chance of being true too.

At some point the degree of weirdness has to level off simply because nothing builds indefinitely and for now global "weirding" appears to be gradually increasing, though as far as I know, precise measurements don't really exist.   It's too hard to quantify.

But it's very hard to compare a world where every 'weird' event gets rapidly broadcast to one even 20/30 years ago where communications were not as extensive and comprehensive.

More water vapour increases albedo surely, therefore more tsi radiated back to space.

If these weirding theories are correct, why have there been no cat 5 hurricanes landfall the eastern America's since Katrina?

CO2 effects are inversely exponential and we've already 'eaten the worst bit' if you like

If you feel the oceans are warming, please cite the paper which supports thus aurgument.


What is the total mass of organic carbon on Earth? What is the estimated total mass of organic carbon plus elemental carbon (defined here as all carbon in any chemical form, minus carbon dioxide, inorganic carbonates, and other fully oxidized carbon species such as urea and cyanates) in or on the Earth's crust, oceans, surface waters, and atmosphere?

You could never have an estimate which was anything more than a wild guess masquerading as an estimate. To estimate the carbon in living vegetable matter alone would be hard enough, and result in a very inaccurate approximation, but to include the quantity in the Earth's crust as well could only be a wild and very inaccurate guess. The exact quantity of all the Earth's oil reserves, coal, peat, limestone and other carbonates isn't known with any precision, then there are oil shales,tar sands, asphalt lakes,clathrates and God knows what else,but the great thing about a sufficiently large, wild guess is that no one could ever prove you wrong, especially as on a few occasions and by sheer chance, guesses turn out to be right!  But it is an estimate, presumably an accurate one that you asked for, and that is impossible.


Is fracking likely to produce earthquakes? Post Christchurch-2011 earthquake, there was much concern that fracking in the surrounding areas might lead to further quakes, as was rumoured to have happened elsewhere in the world.

Is there evidence that fundamentally validates or discredits this?

It's not too too likely, but it can happen. A few earthquakes have either been attributed to fracking, or the wastewater produced from fracking.

According to the USGS (for more information, visit that page):

  Many questions have been raised about whether hydraulic fracturing —
  commonly known as “fracking”— is responsible for the recent increase
  of earthquakes. USGS’s studies suggest that the actual hydraulic
  fracturing process is only very rarely the direct cause of felt
  earthquakes. While hydraulic fracturing works by making thousands of
  extremely small “microearthquakes,” they are, with just a few
  exceptions, too small to be felt; none have been large enough to cause
  structural damage. As noted previously, underground disposal of
  wastewater co-produced with oil and gas, enabled by hydraulic
  fracturing operations, has been linked to induced earthquakes.

So, indeed, the disposal of wastewater has been linked to earthquakes.

This study in Geology also came to the same conclusion that the wastewater of fracking caused earthquakes.

An additional study produced by Ohio geologists concluded that a few small earthquakes were due to fracking. I do wonder exactly what they concluded, but the news story doesn't say. It does say this, but it doesn't say exact what this study was, either:

  A U.S. government-funded report released in 2012 found that two worldwide instances of shaking can be attributed to actual extraction of oil and gas, as opposed to wastewater disposal in the ground — a magnitude-2.8 quake in Oklahoma and a magnitude-2.3 quake in England. Both were in 2011.

I suggest that all the relatively small earthquakes in Oklahoma that have done minor damage are the result of fracking.  I don't know much about earthquake history in Oklahoma but I would not expect the center of the continent to be that active (Cairo, Illinois area being an exception)


Is there any experiment to prove that CO2 with the atmosphere concentration can have greenhouse effect? All gas molecules have the capability to absorb radiation energy. $\rm{CO}_2$ has much less capability to absorb radiation energy, comparing with water vapor.
In Earth's atmosphere currently $\rm{CO}_2$ constitutes only about 0.04% (400 parts per million) of the atmosphere. On average, about 2 to 3% of the molecules in the air are water vapor molecules. In the air the water content is about 50 times higher than $\rm{CO}_2$.
So it seems that $\rm{CO}_2$ content increase in the air should not have any measurable contribution to global warming.
Is there any experiment to prove that $\rm{CO}_2$ with the atmosphere concentration can have greenhouse effect?

Your question about water vapour is quite a common one among people learning about the greenhouse effect. Once you discover the relevant proportions of water vapour and CO2 in the atmosphere, it's perhaps natural to assume that the CO2 can't be playing a major role. In reality it doesn't work like this, for at least a couple of reasons. First, let's look at what the 98% actually means in practice.

It's not just about the concentration

The concentration of a gas in the atmosphere isn't the only thing that determines its warming potential -- otherwise nitrogen, at 78% concentration, would be the most important greenhouse gas. Each gas has a different radiation absorption spectrum, and a different warming potential. So despite its much greater prevalence in the atmosphere, water vapour only has about twice as much long-wave absorption potential as CO2.

At this point, you may be thinking ‘but twice as much is still a lot more, so the CO2 can't be significant!’. But there's another non-obvious factor here, which has to do with the difference between feedbacks and forcings.

Forcings versus feedbacks

In the climate system, CO2 concentration is a forcing, whereas the water vapour concentration is a feedback. To illustrate the difference, here's a crude analogy:

Suppose that I'm trying to lose weight, but I'm reluctant to reduce the 300 grams of delicious chocolate cake that I eat every day. Having read that the human body is around 80% water by weight, I conclude that the cake can't be a problem: after all, I drink 2 kg of water per day, so it would make more sense to reduce that! So I cut down to 1 kg of water per day and maintain my cake intake. Several weeks later, I'm surprised to find that I haven't lost any weight! What's happened? It turns out that the human body regulates its water content, so reducing my intake just reduced my output. Fat storage isn't regulated in the same way, so the cake keeps piling up.

It's a similar story with CO2 and water vapour: CO2 concentration in the atmosphere actually changes for a long time (decades to centures) when we release more gas. Water vapour is, in effect, self-regulating. If we could wave a magic wand and instantaneously remove all the water vapour from the atmosphere, here's what would happen:

(source)

Within 50 days, the water vapour is back to  within 1% of where it would have been without our intervention.

So, if the water vapour concentration isn't controlled by input, what is it controlled by? Temperature. The warmer the atmosphere is, the more water vapour it can hold. This means that when the temperature goes up due to increased CO2, the water vapour content also increases, which further intensifies the greenhouse effect. It's acting as a positive feedback.

Since you're not the first person to ask this question (by a long way), there are already some good resources online specifically addressing the different roles of water vapour and CO2 in global warming.

"Common Climate Misconceptions: The Water Vapor Feedback" is a 2008 piece in the Yale Climate Connections series saying more or less what I've said above, but in more detail and without the cake analogy.
"Water vapour: feedback or forcing?" is a great 2005 essay by Gavin Schmidt explaining the role of water vapour in climate change.
"Explaining how the water vapor greenhouse effect works" is a brief Skeptical Science piece mainly focusing on the positive feedback effect.

Laboratory measurements of CO2 absorption

You seem to be particularly interested in laboratory experiments on
carbon dioxide absorption. As an excellent starting point, I can
recommend the (currently) 26 publications in AGW Observer's list of
papers on laboratory measurements of CO2 absorption properties. If you're really keen to see experimental confirmation that CO2 can still absorb radiation even at atmospheric concentrations, you could take a look at (for example) Taylor and Yates (1957), Yates and Taylor (1960), or Streete (1968), all of which clearly demonstrate that CO2 absorption bands are present in normal atmospheric air.

As an aside: personally I find find that the numerous spectroscopic observations of the whole atmospheric column -- from satellites or ground stations -- provide a more compelling demonstration of the greenhouse effect. After all, the atmosphere isn't a homogeneous bottle of gas that can be faithfully scaled down into a lab sample. But your question and subsequent comments indicate that you're not interested in measurements of the atmospheric column itself, so here I'm just concentrating on ground-level experiments which demonstrate the long-wave absorption properties of CO2.

Answers to comments

  If there is a such positive feedback exist without other negative feed backs, the earth will get warmer without co2 contribution.

I think you might be a little confused about the definition of a feedback here. As I've tried to explain above, the term ‘feedback’ means that the water vapour content is determined by other factors within the climate system. It can amplify the effects of forcings, but it can't in itself ‘push’ the system one way or the other. So you can't have a positive feedback without some kind of forcing: the forcing is precisely the input which the feedback is ‘feeding back’ into the system, in this case via the global temperature increase.

To understand the difference, it might be helpful to think about another form of feedback familiar to a lot of people -- audio feedback through an electric guitar and amplifier system. As you can see in the linked video, there's no sound until the guitarist plays a chord. But once he does play a chord, the guitar pickup itself detects the amplified sound and feeds it back into the amplifier, creating a loop which sustains the sound indefinitely. You can think of the initial chord as analogous to the CO2 input, and the feedback loop as analogous to the water vapour effect: the audio feedback, like the water vapour feedback, doesn't do anything until it's got an initial input from some other source.

  All co2 released from fossil fuel was in the atmosphere during the dinosaurs time. If co2 release from all fossil fuel, it will restore the dinosaurs time atmosphere status. ... you can not deny that those co2 was in the atmosphere in earth history and earth animals and plants flourished

This doesn't really have much to do with your original question! If you want to ask about this, please go ahead and post a new question; StackExchange isn't a discussion site, and we try to keep each question focused on a single topic.

With this in mind, I'll just give a very brief answer here. Your formulation is a little inaccurate: the age of the dinosaurs spans at least 135 million years, there was a lot of carbon burial before it started, and all the carbon currently in the ground wasn't in the atmosphere at the same time. However, it is true that the Earth has seen higher CO2 levels than at present, and that much of that excess carbon is now locked up in fossil fuels. So what would happen if we put a lot of that carbon back in the atmosphere and tried to recreate the high-CO2 atmosphere that, say, T. rex breathed in the Late Cretaceous? Back then, the Earth was a lot warmer, with little or no ice at the poles. One of the biggest effects of re-releasing all that carbon would be the melting of our current polar ice sheets, raising sea levels by some tens of metres. The problem is not that the Earth will become completely uninhabitable by any life form whatsoever (although many current species will go extinct). The problem is that a lot of species, including Homo sapiens, are poorly prepared for a climate change of this magnitude. Ten percent of the world's human population and 8% of its urban land area is in low-elevation coastal zones, and would be completely submerged by a 10-metre sea-level rise -- which is still far less than the sea levels seen during the age of the dinosaurs.

Sea-level rise is just one effect among many, but for now I'll leave it at this since (as I mentioned above) this isn't related to your original question.

  If a person cut his water intake in half, he will get sick before he can get fatter.

This is a little peripheral to the question, I think :-). If you don't like the analogy you can ignore it: it's not essential to the explanation. However, just to reassure you: the EPA Exposure Factors Handbook (2011 edition) gives a mean value of 1,043 ml for the daily drinking water intake of an adult in the US. Thus, I don't think that restricting one's water intake to 1 kg per day, as in my thought experiment, would necessarily cause sickness.

References

Streete, J. L. (1968). Infrared measurements of atmospheric transmission at sea level. Applied optics, 7(8), 1545-1549.
Taylor, J. H., & Yates, H. W. (1957). Atmospheric transmission in the infrared. JOSA, 47(3), 223-226.
Yates, H. W., & Taylor, J. H. (1960). Infrared transmission of the atmosphere (No. NRL-5453). Naval Research Lab, Washington DC.

The key part of this question is “Can CO2 with the ATMOSPHERE CONCENTRATION have a greenhouse effect?”
Assuming this is asking “At current levels, can changing levels of the greenhouse gas CO2 be shown to cause changes in Earth’s temperature?” (Yes, it is a greenhouse gas, … BUT).

The answer is NO. In fact the reverse can be shown, and that “experiment” is practised by astronomers every time they do IR measurements. There’s complete absorption of CO2’s IR wavebands when measured from surface-based instruments for decades. Everywhere, not just on this blog, there’s been much discussion that this IR is re-radiated by CO2 molecules, in all directions, which is true.

However, none of this re-radiation can reach Earth because it encounters a greater concentration, ie higher absorption, in the lower levels. (Note, less than 50% can be directed back to Earth, and this % falls the greater the height of the re-radiation.)One can see this from surface-based instruments (mostly in telescopes) measuring zero transmission of CO2 IR spectra. This could not be zero if it did reach the surface.

[There’s a longer – too long for here – argument presented in Chapter One (plus importantly, its Addendum) at my site “Planet Earth Climate Topics” @ pjcarson2015.wordpress.com.]


Where do aurorae australis begin and in which direction do they move? During a polar night is there any pattern or consistency to where aurorae australis begin?  I'm assuming they become visible first in the exosphere and descend down to thermosphere.  Do they tend to begin and move from east to west, or west to east or is it entirely random?

Auroras start at a distance of 80-200 km above the Earth's surface.

The color of the aurora will be blue/purple if the air molecules in the area below 120 km are excited.

If the air molecules in the area from 120-180 km are the ones that gets excited the colour will be yellow/green.

Above 180 km gives the red light in the aurora.

The most powerful aurora will in general be 180 degree from the Sun's position and it will move from east to west at the opposite side to where the Sun is.

During powerful auroras the aurora arch can easily cover 270 degrees or more if close to the magnetic poles, if the aurora covers the area away from the magnetic poles the aurora arch will get smaller.

When the charged particles from the Sun interact with Earth's magnetic field a powerful ground current will be induced, this can induce DC power in power lines and severely damage the AC power transformers. Should an event like the one that happened on September the first, 1859 (the Carrington event) hit us today we would have major problems with power supply and satellite communication.

You can read more about all of this here, Aurora and please take a look in the sources there too.

Aurora Australis and Aurora Borealis occur as a result of the upper atmosphere being bombarded with sub atomic particles (protons and electrons) from the solar wind. Solar winds are mass ejections from magnetic storms on the sun, and vary in intensity and frequency. These particles are electrically charged and deflected toward the poles by the Earth's magnetic field.

The aurorae have a tendency to be displaced toward the night time side of the Earth and to move very slowly from west to east because the magnetic poles are slightly off-centre and rotate with the rotation of the Earth. Films on TV often show the aurora speeded up, but usually their movement is only barely perceptible to the naked eye. If you can see the background stars moving, the movie has been speeded up. The ones I saw with the naked eye moved very slowly.

There are two main colours. Green is by far the most common, but occasionally the aurora is red. I have seen both from southern England. The red ones are caused by solar wind particles striking and exciting oxygen atoms in the high, upper atmosphere, causing them to emit a reddish light. These particles also vary in velocity, so the more powerful ones are able to reach further down into the atmosphere and stimulate a much stronger emission of green light from nitrogen atoms. This overwhelms the fainter red light from oxygen, so the aurora looks green. They are not often seen from southern England. It sometimes happens, but only in the winter with a very clear sky.


Over what distance can weather be assumed to be constant? Good afternoon,
I'm working on an application makes calls to a weather API for different coordinates across the United States.
Instead of getting the weather at each and every point, I'm planning on clustering coordinates together based on how close they are to each other. That way, I can take an average of coordinates and get a single weather forecast that is representative for the group.
This raises the question, how close do these points need to be? Would a cluster of radius 50 Miles be sufficient? What about 250?
I'm really only gathering these features from my Weather source:

Temperature
Category (Rain, Cloudy, Hail, etc.)
Visibility

I don't really need a high degree of precision. In fact, the coordinates I'm using are going to have a  25-50 mile variation from their "true position."
I'm not a climate scientist, so I apologize if this question is a little rudimentary. I just wanted a second opinion on the topic so I can balance the trade-off between number of API Calls and fidelity to regional weather.

Weather is subject to Tobler's First Law of Geography: Everything is related to everything else, but near things are more related than distant things.
Temperature- this changes not only by the feature, but also the day of the year. The winter months, as well as the fall and spring, will have much more drastic temperature changes. This may be due to things like fronts, but is ultimately caused by heating differences from the sun. However, a few miles can yield quite a drastic change. Things become even more complicated when elevation is involved.
Precipitation- This is even more variable. Snow can be happening on a mountain, but have rain in a valley. Even the side of a mountain can influence how much rain is seen. I have seen it rain on one side of a building, but not the other. Precipitation is a tricky thing to forecast.
Visibility There are several factors that influence visibility. Fog and precipitation are probably the most common meteorological factors. Elevation can really influence your line of sight. Obviously, visibility is also influenced by the presence of smoke as well as dust.The smaller the particle, the more likely it will obscure vision. And snow tends to be more reflective than rain. Something else that may influence visibility is wind speed, as aforementioned particles can be kicked up from the surface. So visibility will change depending on how all of these change. It may even change depending on the direction you look.

All of this to say is that it really depends and there is rule of thumb.

It very much depends on what you are modelling. For example, it's well known that tornados require much more precise modelling than say rainfall.
In fact, good data on tornado formation is scarce given that they are unpredictable and highly localised phenomena.
Even the nationwide scan in the USA that does a scan every five minutes is problematic. Artifacts from this dataset has suggested that they are top down formed whereas recent data from a highly mobile monitoring  equipment has suggested it is exactly the opposite - they are formed bottom-up.


How reliable would measuring global heating from satellite be? Some anthropogenic global heating (AGH) skeptics deny that any global heating is occurring. I figured out a way that could be used to refute them. A weighted average of all of the thermal points on the Earth could be computed on a daily basis. These thermal points are obtained from thermal images.

These points would be satellite resolution distance apart. This would provide an actual measure of global heating. We could subtract out the effects of cities and volcanoes by simply ignoring every value above a certain threshold. One example of such a threshold would be the average of all of the points for that day.

Would this be a reasonable way to double check the trend of global temperature anomalies?

Measuring long-term temperature trends from satellites is possible, but difficult due to a variety of reasons.

This is ongoing research.

In short: the satellites that have been around long enough were built for measuring weather, not climate, and the standards to which instruments need to be built to measure one are entirely different from the other.

We have had satellite measurements of the atmosphere since the 1960s, and operationally since the late 1970s.  Those have always included infrared radiometer measurements, which means that, in principle, we can construct a record of surface (both land and sea) and atmospheric temperatures for the past 40 years at least.  The sensors themselves aren't very complicated — but to determine a trend we would need to be very confident about their uncertainty, stability, and inter-satellite variability.

If you were to simply take 40 years of HIRS infrared measurements and plot them, you don't know if the changes are due to atmospheric or instrumental changes.

From 2015 to 2019, I was part of the FIDUCEO project which aimed to bring the science of metrology (science of measurement) to satellite observations.  Taking 40 years of AVHRR (for sea surface temperature) or HIRS (for atmospheric temperature and humidity) measurements, with 16 different editions of the instrument over a period of 40 years.  But AVHRR was built to look at pictures of clouds.  If you look at pictures of clouds, the user doesn't care if one satellite has its pictures 0.5% brighter than the previous one.  They just tweak their monitor a bit!  But if you take the global climate system, then that corresponds to more than 1K temperature difference, which for the oceans, would be huge.  In FIDUCEO, we aimed to:

Develop a metrology of Earth Observation
Produce Fundamental Climate Data Records (FCDRs) for various operational meteorological instruments in visible, infrared, and microwave, meaning:

Per-datum metrologically traceable uncertainty characterisation;
Per-datum information on correlation structures: which component of the error estimate cancels out when averaging and which component remains;
Harmonisation between the various satellite sensors.

Here are 40 years of HIRS (versions 2, 3, and 4), on which we tried to do some harmonisation.  The top panel shows global average brightness temperature per 24-hour period, as measured by channel 2 which IIRC peaks somewhere in the stratosphere, so this would correspond roughly to an atmospheric temperature somewhere up in the stratosphere (which, incidentally, is cooling as the Earth's surface is warming):

The different colours indicate different satellites.  As you can see, there are both jumps between satellites, and trends within one satellite.  Some of this is expected, as polar-orbiting sun-synchronous satellites have a drifting local equator crossing time, but some of it is due to instrumental problems.  Some of those problems are captured by the structured uncertainty in the bottom panel, but not all of it.  The data only go back to the mid-1980s, because before that, there weren't enough overlaps to constrain the differences between subsequent pairs of satellites based on simultaneous nadir overpasses (SNOs).  For satellites in the early 1980s and late 1970s, the coefficients to calibration the thermometres measuring the temperature of the on-board calibration target appear to have been lost.  For the earliest satellites the header data does not match available documentation.  Software to produce this figure is on Github, raw source data are available from NOAA CLASS, some processed data from FIDUCEO.

This is for a global average.  To do this regionally would add additional complications.

The CLARREO programme is proposed to be the first in-orbit SI reference for accurate calibration.  Had we had that for the past 40 years, our job would be easier.  But CLARREO is still waiting for funding.

So the answer to your question is: with what we have now — not good enough — yet.

But if you are contemplating a career in satellite techno-archeology, I recommend it.  It's great fun.

You seem to conflate several things in your question.

First, AGH skeptics don't deny "climate change". They don't even deny that anthropogenic activity does have some impact on thermal balance of Earth. They just don't think this impact has any significance, since the same climate scientists already have established that CO2 was 10-fold higher in the Earth past, and no water-amplified "runaway" effects (aka "feedbacks") have lead to any terrible effects to life on Earth. It short, there was no "point of no return", historically speaking.

Second, you confuse "global change in average surface temperature" with "global heating". Since the Earth is round and suffers very different insolation levels (equatorial areas are hot and radiate back quite a lot, polar areas are cold and emit much less, all in proportion to 4-th degree of absolute temperature in accord with Stefan-Boltzmann law), it is easy to construct simple examples when lower "average temperature" leads to higher thermal emission, and higher average temperature leads to lower emission to outer space. In other words, there is no correlation between "average surface temperature" of the globe with global "radiative imbalance" (aka "global heating").

Therefore obtaining thermal images from distance might show ANY type of correlation with statistical averages of surface temperatures. And I don't even mention technical difficulties related to long-term stability and calibration of remote sensors, and with necessity to get these observations for at least 100 years to see any effect. And as I noted above, the effect can be anything and prove nothing.


What would it take to confirm or refute the Snowball Earth Hypothesis? Since Harland's sedimentary work and Budyko's models in the 1960s, geologists have hypothesized that the Earth may once have been completely frozen. There are various lines of evidence for this event.

What would it take to conclusively confirm or refute this hypothesis, short of going back in a time machine?

In order to confirm the snowball earth hypothesis, we'd need at least:

A paleogeographic model which extends to greater than 650ma and has been shown be be conclusively accurate throughout that entire period. (i.e. one we can trust)
Sedimentation structures/patterns (or other paleoclimate proxy data), consistent with a glaciation event, tied into the same time period, from the north pole to the south pole

Bennet et al showed that there are several origins of the 'dropstones' not associated to glacial deposits. The dropstones are the sole material, circunstantial, presented as evidence of global glaciations.

The whole story started because of the Faint Young Sun - only 70% of energy output leads to a frozen Earth - a Paradox because there was liquid water on Earth and Mars that required a Hot Past. The same with Mars Hot past (the CO2 feedback as a source of heat preservation was dismissed recently).

We have already strong biological and geological evidences, that can not be dismissed, against the Snowball Earth old theory:

Molecular phylogeny - Life’s evolution is strongly dependent in ambient thermal evolution as recorded by Life itself and demonstrated in:

The resurrected proteins - Paleotemperature trend for Precambrian
life inferred from resurrected proteins, Nature 451, 704-707 (doi:
10.1038/nature06510 Letter)”. Gaucher & al., 2008.
Reconstructed ancestral enzymes suggest long-term cooling of Earth’s photic zone since the Archean – Amanda Garcia et al, 2017

Geological records have the same trend of high temperature in the past (∂18O(Knauth & Epstein, 1976) or of ∂30Si (Robert & Chaussidon, 2006) indicate a sea temperature above 65 ºC, eventually close to 90 ºC, earlier than 2 Ga. Several other studies confirm the results.
The Life, ie all cells - can only use monoatomic N(itrogen) that is not freely available on Earth. The atmospheric molecular N2 require huge pression and temperatures to be dissociated in N+N as used in the Haber-Bosch process invented in the start of XX century (ammonia to fertilize the soil and feed the humanity - growing exponentially since the 30s). Until then Life had to feed on itself (a shitty recycle) and the total bioma could not grow.
The habitat of the most ancient life forms are in the thermal vents (very high temperature and pressure)
The mammals and birds – the last major Life's creation – are equipped with protective furs and feathers and the internal metabolism novelty to keep the ideal temp around 40ºC and the species unadapted to colder times got extinguished
The proto-feathers favoured the Heat dissipation (see image bellow)

The conclusion can only be: The Snowball Earth Theory is dead.
But ... to solve the conundrum we have to put the planets closer to the Sun in the past or increment it's energy output. A new theory?

A paradigm shift was motivated by the following considerations:

A rationalistic mind, following Descartes, Spinoza and Poincaré...,
can never accept that the space is expanding at the expense of
nothing, without a cause.
We measure everything with atomic properties (atoms), thus, we can not measure the evolution of the atom itself; f.i. the mass unit ‘kilogramme’ is the mass of an ensemble of atoms as represented in Paris prototype. Thus, one atom’s mass is a definite part of that unit – a definition in loop - and the same definition holds true, and the universe keeps going, if in the past the atoms were a billion times larger than the ones we have now.
The redshift of the radiation we receive from the past can be
interpreted as the emission from larger atoms

Two studies were concluded outside the academia (not peer reviewed - blame the system and not the author):

A rational explanation of the observed space expansion is derived in A self-similar model of the Universe unveils the nature of dark
energy and it is formally proved that the atoms are shrinking (the units Mass-Charge-Length-Time evolve at the same pace - to source the energy of the electrostatic and gravitational expanding fields). The obvious consequence is that the space seems to be expanding.
From the available data the Evolving Climate Model (ECM) was derived - A model of past Earth’s climate from isotopic and biologic data and its relationship with orbits’ expansion and the initial environment favorable to the Emergence of Life is obtained. An abiotic origin  of Earth' Oxigen is presented and why Life was able to capture all the monoatomic N it uses.

Edit add:
Some (a lot of) people have prejudice against new ideas that appear out of the academia. In this case the new ideas grew in front of my eyes decades ago and if you find any error or anything to be better explained in those docs you can ask me. Be polite and do not pretend to judge them without reading the content as it seems to be the usual case. The first doc has more than 1000 downloads and not a single error was mentioned until now. Be the first to argue.

Quoting 'ressurected proteins' doc:

  Our results are further supported by a nearly identical cooling trend
  for the ancient ocean as inferred from the deposition of oxygen
  isotopes. The convergence of results from natural and physical
  sciences suggest that ancient life has continually adapted to changes
  in environmental temperatures throughout its evolutionary history.

Fig 3 from the 'ressurected proteins' doc with the past temperature on Earth as recorded by Life that is incompatible with SBE

(proto-feathers - Ramphorhyncus longicaudus at Teylers Museum – Haarlem)

Edit Add:

Due to the fact that basic logic is absent in the comments ( ‘Atoms are not shrinking. I assume the rest of this answer is equally silly’)  I’ll have to extend the implications of the Considerands above expressed to show that the downvotes are due to the lack of appropriated knowledge of laws of Logic and/or Physics. Playing with Legos or scaled trains/cars, designing Computer Models of the reality or engineering scaled material models (similitude) can give a better insight of the solution here briefly described.

The 2nd consideration “We measure...” was intended to show explicitly that the units of measure are in one to one correspondence with the atom properties with the example of atomic mass. It is obvious, by definition, that the same is true irt the charge unit. The length unit can be assumed to be in a one to one correspondence to the atomic Bohr radius. Assuming the constancy of the light speed ‘c’ the Time T is tied to the Length unit. The simple and intuitive mode of reasoning is this one ‘without atoms we have no units of measure at all then it follows that the units are in correspondence with the atom, whatever its actual ‘size’’.
From this I see a logical error in the statement  “Atoms are not shrinking” because no law of physics have stated that and I’m sure that it is not missing such law.

To hold the validity of physical laws requires to hold the invariance of non-dimensional combination of quantities and constants (e.g., $\pi$ theorem); this implies that the relationship between correspondent base units has to be the same. Thus, the units Mass M, Charge Q, Length L, Time T had to evolve at the same pace, lets say
$$\frac{[M_0]}{[M_1]}=\frac{[M_0]}{[M_1]}=\frac{[Q_0]}{[Q_1]}=\frac{[T_0]}{[T_1]}= \alpha(t)$$ and $\alpha$ function is the atomic scaling function.
The velocity is invariant $\frac{L\alpha}{T\alpha}$
The energy scale function is $\alpha$; being
$E_0 =  M\ L^2\ T^{-2} \\
E_1= M\alpha\ L^2 \alpha^2\ T^{-2}\ \alpha^{-2}=E_0\alpha $
The acceleration and gravitational field $L\ T^{-2}$ scale as $\alpha^{-1}$

Lets see some examples:
The electron mass $m_e$ is left as a free parameter in Quantum Mechanics and in Atomic Physics but the ratios of the masses of particles have to be the same.

The 3th consideration: “The redshift of the radiation we receive from the past can be interpreted as the emission from larger atoms” was scrutinized at PSE and showed the impossibility to distinguish the spectrum of the atomic radiation emited from an atom in motion and the one of a scaled atom - PSE  as acknowledged by the author of the  accepted answer, after clarification that Wolfram equation on the hyperfine structure he used was indeed wrong.

Lets see that the Force is invariant under that transformation:
Newton 2nd law $F=mass\ \cdot\ acceleration$ (in SI units $kg*m/s^2$) and in dimensional analysis
$F_1=\frac{M\cdot\ L}{T^2}=\frac{M\cdot\ \alpha\cdot\ L\cdot\ \alpha}{(T\cdot\ \alpha)^2}=F_0\cdot 1$
The force of gravitation (Newton) has the same value $F_g=G\cdot\frac{M^2}{L^2}=G\cdot\frac{(M\ \alpha)^2}{(L\ \alpha)^2}$ and the same is valid to the electomagnetic Coulomb force.
The parameters $G,\varepsilon_0,c$ are invariant and the same irt the dimensionless constants.

From the list of the dimensionless quantities
we can pick any of these and check what happens, f.i.:
The  Eötvös or Bond number ( related to the shape of bubbles or drops)
$E_0=B_0=\frac{\delta\rho\ g\ L^2}{\sigma}$
where $\rho, g, L, \sigma $ are density, gravitational acceleration,   characteristic length and surface tension and in SI units $E_0\ units=[E_0] = \frac{kg/m^3\cdot m/s^2\cdot m^2}{kg*m/s^2/m}$ and inserting the scaling value we get for the system 1 the same value [E_0]
$[E_1]=[E_0]\cdot scaling(\alpha)=\frac{kg/m^3\cdot m/s^2\cdot m^2}{kg\cdot\ m/s^2/m}\ \cdot \frac{\alpha/\alpha^3\cdot \alpha/\alpha^2\cdot \alpha^2}{\alpha\cdot\alpha/\alpha^2/\alpha} \\
=[E_0]\cdot \frac{\alpha^{1}\ \alpha^{-3} \cdot \alpha^{1}\ \alpha^{-2} \cdot \alpha^2}{\alpha^{1}\cdot\alpha^{1}\ \cdot \alpha^{-2} \alpha^{1}} \\
=[E_0]\cdot \alpha^{1-3+1-2+2-1-1+2-1} \\
=[E_0]\cdot \alpha^{0}=[E_0]$

The 1st consideration  is a basic tenet of physics that never should have been forgotten and was indeed in the minds of all the physicists a century ago.  The difficulty of finding the correct explanation of the measured space expansion, besides the naif one: ‘the galaxies are moving away’ brougth philosophical problems and magical entities like the ‘dark’ energy, BB, inflation period, etc… in what in the universe is forbiden: ‘free lunches’.
This new model is not a theory but a model because it was drawn from data with no ‘IFs’ and no hidden or undeclared, unverified, postulates like the one ‘the atoms are not shrinking’. Because in the laboratory there is no feasible experiment to make evident that the atoms evolve, or not, one can not jump to a conclusion without the theoretical analysis like the one done in this model.
The actual function that describes the scaling of the matter was deduced to be $$\alpha(t_S)=e^{-H_0\cdot t_S}$$ and $t_S$ is the time unit of the system $S$ used as reference, a non evolving one.

In the meantime I’m traveling the desert receiving up and downvotes from individuals that did not studied this issue and have no other way to answer the million dollar question, except ‘I assume/believe’:
Is it the case that the space expands or the atoms that are shrinking?

Now we have enough data and knowledge to say that the Snowball Earth theory is dead because it was proved wrong by the Life itself and by the geological records.

A final remark - I commented that the temperatures on the graph are lower than the real ones because a rise in the temperature makes the seawater to migrate to the atmosphere and the pressure and the boiling point rises too.  The studys only considered a standard  atmsphere of 1 bar.


In a zero carbon future but with increasing energy requirements would Earths oceans continue heating? We’ve completely obliterated our reliance on carbon based fuels. All our energy comes from renewal resources or even fusion. Our energy requirements continue to rise. Taking this to a deliberately ludicrous degree, whereby we’re capturing the sun’s energy, planet wide, via solar panels, we would essentially be diverting large amounts of sunlight that might otherwise have reflected our radiated back into space into our energy networks. Whatever that energy is used for our will ultimately be transformed Into heat. Some of that heat will be emitted into space via radiation, but I can’t help wondering if much of it will just stick around and continue to heat our atmosphere and oceans. Could our energy consumption increase indefinitely without affecting the ability of Earth to support our current ecosystem; or will be ultimately have to limit our energy use?

Edit for disambiguation purposes:
I'm not sure my original question at posed has been understood. Ignoring existing greenhouse gas emissions, in fact ignoring any issue with GHG at all, as civilization advances and our energy requirements continue to rise, the energy that we do use to perform work will ultimately be transformed into heat. We'd basically be pumping heat into the atmosphere instead of GHGs. A hotter atmosphere still holds more energy and moisture. Could we end up overproducing heat via fusion? Or is radiation an effective way for the planet to balance this excess?

Short answer: Yes, the ocean would continue heating for a while if we cut off all greenhouse emissions. Simply because CO2 has a long life span in the atmosphere and its effects will continue to be active for a long time, longer than human life spans.

Also, it may be that thresholds have already been passed that lead to positive feedbacks, like glacier retreat or desertification that amplify the forcing effects of greenhouse gases. Deforestation and wild fires are another such positive feedback, they release a lot of CO2 for immediate warming effect and expose a surface ready to be eroded and not available as a carbon sink any more.

The great hope for a carbon neutral future is, as you suggest, fusion power stations. Scientists are making good progress in this direction, but a commercial reactor is still two or three decades away. We won't have to limit the number of reactors because their production of dangerous wastes is negligible compared to fission reactors. The heat they will produce is not a problem either, as it will be dwarfed by the heat from natural sources like the sun and geothermal. Much of the small contribution our reactors make will radiate away into space.

We will have to limit our energy use for the simple reason that we will have to limit our population. The Earth does not have unlimited resources and populations cannot continue growing indefinitely. If we don't limit them ourselves in a planned and orderly way, nature will do it for us, and in the scramble for increasingly scarce resources, wars will become more likely. Water scarcity is already threatening to bring war to the Middle East and Africa. Whether the oceans will heat significantly before the carbon neutral energy sources can fully take up the task of providing our energy requirements, we shall have to wait and see.


If the distance between Earth and the moon were changed, would the effects be immediate? I need your help on a possible (but perhaps low probability) scenario for how the distance between Earth and the moon could change: say a large object from the Kuiper Belt manages to make its way into the inner system. It passes by our moon such that its gravity changes the moon's orbit around Earth into a more pronounced ellipse. So there will be times when the moon is much closer to Earth and other times when it's further away than its current distance from Earth.

Say that this change in the moon's orbit isn't enough to cause an apocalyptic scenario for life on Earth but that the tides are of course much, much more pronounced. I surmise that the greatest impact would be felt in costal towns and cities around the world. My question is: how long would it take for the change in the moon's orbit to be felt on Earth? Are we talking almost immediately/ within the hour for some unlucky areas that are now much closer to the moon on its new orbit, and at most within 12 hours for the "luckier" areas? Or would the time frame be much longer?

Thank you in advance for any insights you could offer on this.

The moon's orbit might have changed, but obviously it would take some time before this would become visible. The moon's position iself would probably not be that affected by the event as its inertia is too huge. So the tides would probably not be noticeably affected in the first hours.

I have no idea really how long, but it might not take too long before, depending on what point of its new, elliptical orbit the moon is now positioned - is it now approaching earth, or more or less staying at the same distance, or to the contrary getting farther away - the tides will start to be affected.


Iron-nickel phase in pallasite meteorites I have recently been learning and researching about meteorite types and classification. Pallasites are mainly composed of a 'solid-solution' of olivine crystals and an iron-nickel alloy. My question is: what is the phase of the iron-nickel alloy, in a body-centered cubic crystal structure (alpha-iron, and hexahedrites) or face-centered cubic?

First, a correction. A solid solution is between different compositions in the same phase. For example, olivine is a solid solution of forsterite (Mg2SiO4) and fayalite (Fe2SiO4).
There are two common iron–nickel alloys found in meteorites (pallasites and others): kamacite and taenite. They are commonly intergrown into lamallae called "Widmanstätten pattern". It looks like this:

Kamacite has up to about 10% nickel, whereas taenite can get up to ~60% nickel, but commonly found up to 30%.
Kamacite has the space group Im3m, making it hexoctahedral body-centered. Taenite has the space group Fm3m, making it hexoctahedral face-centered.

The metallic part ( essentially all two elements= Iron + nickel) is two phases mixed together : Body Centered Cubic - magnetic, and Face Centered Cubic - nonmagnetic. So the answer to your question is that it is both .  Iron ( BCC) starts to form FCC when Ni exceeds 6 %. The proverbial 18 - 8 stainless steel is 8 % Ni and generally non magnetic austenite phase. My educated guess is the classic  Widmidststten pattern is ferrite ( BCC ) grains/crystals forming from the original austenite ( FCC ) grains/crystals. But it is not that simple as when hot ( 1500 F ) it is 100 % austenite ( FCC ). Further complication is the austenite ( FCC , nickel rich) makes crystal twins . The twins can also give the Widmanstratten structure. And more complicated because temperature history can also affect the FCC / BCC morphology.  [ Maybe I cheated but I searched meteors on the net and learned some but also found some mistakes in the references. ]


Could one say that granites are metamorphic rocks, or not at all? In my old textbooks, granites used to be part of the metamorphic rocks.
Is this still true or not ? If not fully true, to which extent ?
Could someone point me towards clear examples or definitions showing they are considered not metamorphic rocks any more ?

If not metamorphic, please which part of the rock classification do they belong to exactly ?

Thanks,   Gilbert.

This is the key:

  used to be part

It is important to look at this from a historical point of view. Up until the 1950s and early 1960s, there was no agreement to how granites form. This became the granite controversy.

On the one hand, experimental work showed that granites crystallise from magma, but this magma had to be derived from basalt-like magmas. This led to two problems:

Where is all the basalt from which the granite was supposed to form?
What happened to all the rock that was there before the granite (aka the "room problem")?

This led people to think that granites formed by metasomatic replacement of other rocks. Essentially, you have other things than were not granite and then they were transformed to granite through various geological process, without ever crystallising from magmas. This is what people say when they talk about granites as metamorphic rocks.

But, this is not the case and later research demonstrated that granites from by crystallisation of magma and the process of metamorphic formation of granites (by metasomatism, or "granitisation") does not actually exists. There were (and still are) many questions left unanswered on exactly how this happens, but we know that this does happen and granites are indeed igneous rocks. In fact, there's a great paper published just this week in the journal Nature, showing modelling of how some of these things can form.

Nevertheless, granite formed can be sometimes related to metamorphism. Extreme cases of hot metamorphic can cause melting of (previously sedimentary and then metamorphic) rocks to form magma that eventually crystallises as granites. This is known as migmatisation, and is commonly used to explain the widespread occurrence of "leucogranites" in the Himalayas for example.

Additionally, some high-grade metamorphic rocks contain quartz, feldspars, micas, and amphiboles. The metamorphic texture (foliation and lineation) is not always obvious, making it easy to mistake metamorphic gneisses as igneous granites.

According to google, granite is an igneous rock. And as I said in my comment, it has several different other rocks that are formed within it, such as quartz or feldspar.

Some people may tell you that granite is a sedimentary rock, but based on the way it is formed (by magma cooling beneath the earths' surface) it is considered    an igneous rock.

More information at geology.com.


Differences between linear airy wave theory and Stokes' 5 wave theory? and it's application What is the difference between linear airy wave theory and 5th order Stokes wave theory? What is the differences in terms of application. I am looking more on offshore structure analysis aspects.

Thanks.

You should find what you're after within the following:

https://rules.dnvgl.com/docs/pdf/DNV/codes/docs/2014-04/RP-C205.pdf

If not, one of their other documents should contain the information.
I hope this finds you well.


Will increased precipitation in Antarctica prevent sea level rise? It has been suggested that global warming will lead to increased precipitation in parts of Antarctica. This would sequester water in the ice sheet, preventing sea level rise.

However, the slope (and thus the height and volume) of continental ice sheets is limited by ice properties. What if the ice sheet is already at its maximum slope/height/volume (is this known)? Wouldn't adding more ice just cause more flow to the sea?

According to "Ice Sheet Modeling"

  ice behaves as a deformable plastic material, which means that there
  is a critical shear stress, below which no strain (deformation or
  flow) will occur ... If the slope is too low, the basal shear stress
  will not match the critical shear stress, ... but as snow piles up,
  ... flow will begin. ... The result of this is that a glacier has an
  equilibrium profile

I am presuming that the ice sheets are already slightly above their equilibrium profile (since they are flowing). Since the profile depends on the area and shape of the base (which is shrinking due to melting around the edges), they are already holding as much ice as possible, and adding more snow to any region will just accelerate the flow. I don't know on what timescale this occurs. (I have not tried the computer models described in the paper.)

There is some scope for continuing debate because quantifying the various components of the ice/snow/water balance are fraught with difficulty, and many of the estimates have error bounds which approach the magnitude that is being measured. However, a good best estimate, subject to continuing research, is given in:Is Antarctica losing or gaining ice?
This cites the following two graphs:

Clearly there are important regional differences, with East Antarctica gaining slightly, but not enough to compensate for the ice loss in west Antarctica.

It is true that the amount of fresh snow in the Antarctic is increasing, but it still doesn't amount to much. Antarctica is still the driest continent, by far, and much more so than Australia. The controlling factor is not the amount of snow on the land, but the fate of the sea ice around the perimeter. Notwithstanding climate deniers, there is abundant evidence that the oceans' sea surface temperatures are warming, including the Southern Ocean. This reduces the seasonal extent and thickness of sea ice, which lowers the oceanic albedo, and increases near-surface heat absorbtion. It is a well-documented feedback process. Overall the warmer ocean around Antarctic destabilizes the shelf ice, thereby unlocking the glacial ice which would have been held back. So we have two opposing non-linear processes, mobilization of coastal land ice (mass loss), vs increased snowfall (mass gain). At present, and for the forseable future, the mass-loss is winning. I'm guessing this will continue to be the case because the negative feedback is very powerfull. I don't think there are any reliable forward projections about how precipitation in the Antarctic will evolve.

(Later) In view of the comments, maybe it would be helpful to visualize the daily precipitable moisture around the world. This is available at El Dorado Weather.

I want to support other arguments with the historical one.

All we know that since the Last Ice Age the Sea Level has increased by .. 120 meters

For some reason (I guess explained by now: it is too small and experiencess net loss of ice instead of build up), Antarctica did not stop the raise. Antarctica never hampered the sea level rise and fall along with the global temperature. Which magic do you expect to turn the tide? Why should antropogenic nature of the human-induced warming should revert the trend?


Velocity from time and depth seismic images I have a seismic dataset that contains a depth-migrated seismic (amplitude) volume in depth and then the exact same volume converted to time using the migration velocities. Unfortunately, I do not have the velocity volume used to do the conversion.

How can I extract the velocity volume using only these two (amplitude) volumes?

Since the signals are exactly the same, just stretched and squeezed, I believe the solution will require something like dynamic time warping but I don't have enough experience with this to make it work.

Since each trace in the volume is converted independently, this reduces to a 1D problem. An optimal solution for a single trace can be used to solve the entire 3D volume (unless there is a lot of error and then we can have lateral instability, but I can live with that).

I will eventually need to code it in MATLAB for application on sgy-formatted data.

Disclaimer: It a very crude way to do it.! Take it as the last resort.

It assumes that you know velocity for the shallower reflectors/layers. I will explain for one reflector and you can extend for deeper reflectors.

Step 1. You slice out the reflector event (in a trace) you want to find the velocity for.

Step 2. Take a correlation with the respective trace in other time/depth domain part and find the max correlation time/depth. Here you may assume this time corresponds to the respective depth so you get total travel time.

Step 3. At this point you know the interval velocities for layers at the shallower depth, so you can find out the interval velocity for this layer.

You start from the top and continue to bottom side. You may treat it as layer stripping.


At the ocean surface, why do large amplitude waves travel faster than small amplitude waves? I understand the mathematics behind it but I am looking for an intuitive description.

Higher amplitude waves, on water, are caused by larger disturbances and longer durations of energy input, in the form of wind, than smaller ones. Quite simply in order to build a big ocean wave you need to put in a lot of acceleration of surface waters over an extended period of time. So it's not just that the wave itself is travelling that much faster, the whole surface that the wave is moving on is itself moving in the same direction as the wave on the surface. The larger amplitude of the waves is in fact partly due to them going faster rather than the other way around.

NB: This doesn't apply with Tsunami waves as those are full column disruptions involving the water column from seabed to wave crest.

This falls under the basic principles of physics - the higher the amplitude, the more energy. The ocean is the material that is being used, but think of it as an isolated wave of energy. Under any application - light, sound, etc - the higher the amplitude a/o frequency, the more energy. More energy = more speed.


Is Cape Canaveral really the lightning capital of the US? Today's SpaceX webcast featured an interesting quote, that Cape Canaveral is the lightning capital of the US. Is that really the case? If not, how does it compare in lightning strikes to other areas in the US?

It's pretty likely. Florida has the highest lightning strikes of anywhere in the US, as can by seen by this map from lightningsafety.com This is the area near Florida, with the highest levels.

It's hard to see, but the highest density is actually just to the west of the Cape, but it's not too far of a stretch to say it's the lightning capital of the US.

Central Florida is a zone of convergence; prevailing winds from the north crash into prevailing winds from the south.  The result is a lot of storm activity and a lot of lightning.


What would be the temperature of earth if there was no atmosphere? I do know that the atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect),and reducing temperature extremes between day and night (the diurnal temperature variation). I wonder what temperature would earth reach if there was no atmosphere?.

According to Wikipedia an approximate average surface temperature for a bare earth is 274.5 K. This scenario is quite reasonable in my opinion as stripping the atmosphere without changing much else would (on a geological timescale) rather quickly result in a bare earth without ice caps or vegetation, causing circumstances quite close to those on the moon. (I assume the Earth's magnetic field protecting both the atmosphere and life below it has disappeared as well)

This is estimated by comparing the black body radiation of the Earth and Moon, which is then corrected for albedo (fraction of incoming radiation that is reflected) and emissivity (ability of a material to emit radiation), which are properties of a material. Since the Earth and moon are both at the same distance to the sun and made up from the same material on average, measurements of the albedo and emissivity of the moon can than be used as estimations of these properties for the Earth.

The black body radiation of the sun is calculated with the Stefan-Boltzmann law:

$$P_{\text{S,emit}} = 4\pi R_S^2 \sigma T_S^4$$

$P_{\text{S,emit}}$ is the emitted energy by the sun, $R_S$ is the radius of the sun, and $T_S$ is the temperature of the sun. The fraction of this energy recieved by the Earth is then proportional to the circular surface area facing the sun and the energy density at the distance $D$ between the Earth and the sun.

$$P_{\text{SE}} = P_{\text{S,emit}}\left(\frac{\pi R_E^2}{4\pi D^2}\right)$$

$R_E$ is the Earth's radius. Using albedo $\alpha$ the absorbed energy can be calculated:

$$P_{\text{E,abs}} = (1-\alpha)P_{\text{SE}}$$

Applying the Stefan-Boltzman law to the Earth, corrected for the emissivity $\overline{\epsilon}$, the emitted energy is then:

$$P_{\text{E,emit}} = \overline{\epsilon} 4\pi R_E^2 \sigma T_E^4$$

Assuming energy equilibrium $P_{\text{E,abs}} = P_{\text{E,emit}}$ we can now calculate $T_E$:

$$\begin{aligned}
\frac{(1-\alpha)4\pi R_S^2 \sigma T_S^4\pi R_E^2}{4\pi D^2} & = \overline{\epsilon}4\pi R_E^2 \sigma T_E^4 \\
T_E^4 & = \frac{(1-\alpha)4\pi R_S^2 \sigma T_S^4\pi R_E^2}{\overline{\epsilon}4\pi D^2 4\pi R_E^2 \sigma} \\
T_E^4 & = \frac{(1-\alpha) R_S^2 T_S^4}{ 4\overline{\epsilon}D^2  } \\
T_E & = \left( \frac{(1-\alpha) R_S^2 T_S^4}{4 \overline{\epsilon}D^2 }\right)^{\frac{1}{4}} \\
T_E & = T_S \left( \frac{(1-\alpha) R_S^2}{4 \overline{\epsilon} D^2 }\right)^{\frac{1}{4}} \\
T_E & = T_S \sqrt{ \frac{ R_S \sqrt{\frac{1-\alpha}{\overline{\epsilon}}} }{2 D } }
\end{aligned}$$

Finally we only need to insert the correct values:

$R_S = 6.96\times 10^8$ m
$T_S = 5778$ K
$D = 1.496\times 10^{11}$ m
$\alpha = 0.1054$ (assuming value of the moon)
$\overline{\epsilon} = 0.95$ (assuming value of the moon)

This gives us a temperature of 274.5 K.

Note that there are many factors that can cause local and temporal variations. For example, incoming radiation varies with latitude and season, and if the removal of the atmosphere would be caused by a dying sun that grows to engulf the earth temperatures would be much higher than this. All in all, to account for all those factors a very large model must be made that can analyse the influence of each factor, including the decrease in temperature of a dying sun etc., but that would be nearly impossible to build if only for the resources it would take to do so.

Since one of the most contested factors is the albedo after the atmosphere is removed the following graph shows how the average surface temperature changes with albedo. At an albedo of zero all incoming solar radiation is absorbed, while at 1 all radiation is reflected. Note that the temperature of 0K is an effect of the assumed equilibrium between incoming and emitted radiation, which will not hold at that point. As said above, the albedo for a bare earth will be approximately 0.1, while current values on average range from 0.3-0.4, largely contributed to by clouds. An average for the albedo of the Earth in its current vegetated state, but without clouds I haven't been able to find.

As stated by @ardie-j in his answer, another possible fate of the Earth could be that it gets covered in ice, as another Snowball Earth Event. In that case the albedo would rise to levels ranging from 0.4-0.9, resulting in a drastically cooler Earth.

Sunlight is 393 Kelvin. The earth is irradiated at half the surface area that emits the radiation. And the radiation is absorbed in a spherical volume. So:
$((σ393^4/(4/3))/2=510W/m^2$ or 308 Kelvin(32 degrees celsius).


What impact on climate did 2011 earthquake and tsunami have? The 2011 Tōhoku earthquake and tsunami was one of the biggest in modern history; the earthquake even moved Earth's axis for a very small, but measurable bit. The four years since then is not enough for hard climate data, but enough to have some insight to how the weather was influenced. So did it influence weather in any way that could be seen as "impact on climate"? If yes, how?

Local effects are definitely possible, mainly from the tsunami itself - turbulence in the air from the waves and increased evaporation from flooded areas after.  However, it appears that the earthquake and tsunami has had no significant effect on the world's weather, particularly in the long term.  According to the Lamont-Doherty Earth Observatory, Columbia University web-article, Can Big Earthquakes Disrupt World Weather?, a key point is that although the earthquake released a massive amount of energy, it is not enough to disrupt the energy balance of the atmosphere.

A particular point is that one of the significant effects - the axial shift from the earthquake, is, according to the article, minimal compared to natural cyclical axial fluctuations.  The article also mentions that other major earthquake and tsunami events have the same minimal effects.

Although, some studies such as what gansub mentioned in comments, Impact of tsunami on Tamil Nadu Monsoon Rainfall, suggest that the tsunami itself can cause disruptions to local and regional climatic systems  -particularly with rainfall patterns.  This is an ongoing study by the University of Canterbury's Dr Iman Soltanzadeh research "The Atmospheric Impacts of Volcano and Large Tsunamis" where land use modifications due to a tsunami would affect local and regional climate and weather patterns.

However, the effects on the thinner upper atmosphere were a bit more pronounced according to NASA observations reported in the web-article Quake and Tsunami make waves in the Atmosphere, causing ripples in the ionosphere (~85km above the surface), as can be seen in the image below:

The quake caused acoustic and Rayleigh waves that reached the ionosphere in about 10 minutes, and the rolling motion of the tsunami caused gravity waves to propogate to the ionosphere in about 30-40 minutes, continuing westward even after the tsunami was stopped by the east coast of Japan.

The most significant aspect of NASA's findings can be interpreted that as the waves (all types) propogate through the atmosphere from the earthquake rupture and tsunami to the ionosphere, they appear to cause no significant climatic disruption to the lower near-surface and even the middle layers of the atmosphere, further emphasising the conclusions made by the Lamont-Doherty Earth Observatory that large earthquakes and associated tsunami do not cause any long term affects on weather patterns.

False! the tsunami caused major upwellings of cold subsurface waters and even slowed, temporarily stopped or shifted some ocean currents. All this led to the drought that plagued the west coast for years, until the Humbolt current resumed it's normal path. Many other recent weather anomalies since 2011 can be blamed on this Tsunami and it's lasting effects.


The origin of permafrost Old permafrost is loaded with frozen vegetation.  As it now melts, it is rotting and releasing methane.

Doesn't that mean that it froze quickly, centuries ago, and stayed frozen until now?

What process caused such a sudden, centuries-long freeze? Don't we need to know this before we understand why it's reversing now? Presumably we humans had nothing to do with the freeze!

What caused a centuries long freeze, the beginning of the current ice age. Yes we are in an ice age, as long as greenland and antarctica have large ice sheets we are technically in an ice age) Which in turn was caused by the movement of continents close enough to the poles to create permanent ice caps. the freezing of organic matter into permafrost is not a fast occurrence, it is a slow build up of organics as soil is built and added too, as long as it remains cold enough for permafrost to persist.

The strange thing about the warming now is every major natural factor and most minor factors point towards cooling conditions yet we have warming. Human activity however is producing strong warming factors that are overriding the natural prevailing conditions, which makes you wonder what will happen when some of the natural factors stary cycling back to warming.

Vegetation in Arctic and sub-Arctic bogs is not necessarily rotting. After a while the vegetation in a bog creates an acidic environment that preserves plant material and animal remains as though they were pickled in vinegar. That is why in Britain and Ireland there are extensive peat bogs many thousands of years old, and coal deposits which began in a similar way. In dryer places it is possible for plants and animals to be suddenly overwhelmed by winter conditions and to stay frozen for thousands of years, and these might generate CO2 and methane when they are frozen out.

A famous example of quick freezing is the bronze age warrior known as the Ice Man, who was found about 15 years ago frozen in the Italian Alps where he was overcome by a snow storm when he tried to cross in about 3,000 BC. So the answer is that some of this vegetation froze quickly, but most of it didn't, or at least was already preserved when it froze. It is possible that there have been brief episodes of thawing since then, so the freezing was not necessarily continuous. Some will decompose when it thaws completely, and some won't.


Prevailing winds between 30 to 60 degrees latitude Prevailing winds are generated by Coriolis effects.

I think I understand why NE winds are the prevailing winds in 0 to 30 degrees and 60 to 90 degrees latitude in the northern hemisphere (e.g., according to the picture below). But I don't understand why westeries are the prevailing winds in 30 to 60 degrees. If one throws a ball from a point at the equator to the north pole, shouldn't it deflected to the opposite direction by the direction of the rotation of the earth (i.e., creates SE winds)?

Although not 100% sure, after some additional searches, I think the answer is the law of inertia. If one throws a ball from at the equator to the north pole, the ball also moves to the right even if one did not intend to do so. The same effect we see when one throws a ball from a moving car (example).

The speed is faster near the equator. Therefore, even through Coriolis effect is working, the law of inertia overrules the effect. That is, the movement (to right) of the ball is faster than the rotation of the earth.

Regardless of from north to south, or south to north, Coriolis effect and the law of inertia work in opposite directions. Stronger one determines the direction.


What is it called when water forms to look like a root structure? I've tried looking it up on google but I can't find anything. I'm talking about when a small amount of water forms to look like a root hair structure, thin and branching out.

The term you are looking for is Dendritic, it literally means "having a branched form resembling a tree" and is used to describe the shape of rivers but can also apply to anything with that pattern.

Given that you are talking about something small and root-hair like there are no such examples occurring with water in the liquid phase.

It's more likely you saw ice. In science jargon, what you're referring to are known as fractal structures. Below the pictures, I explain why water in the liquid phase can not produce the specific type of fractal structures you're asking about.

If the photos below are not even close to what you were thinking of, and you're sure it wasn't ice, then you probably saw something that wasn't water (for example a clear mold).

There's literally an infinite variety of these fractal ice patterns. Try googling the terms fractal, self-organized, self-similar, self-affine, patterned, or dendritic, complex network followed by any of the words frost, ice, ice-crystal, snow, snowflake.

In response to comments, it's worth clarifying why small amounts of water cannot form static fractal structures. Water has strong surface tension resulting from the polarity of individual $H_2O$ molecules. Surface tension is the reason water beads up to form smooth edges, which is precisely the opposite condition of fractal structures. There are examples (like the structure left behind as water drips down a window) of limited branching with water, but the branching is physically limited by surface tension that forces smaller nearby water to coalesce with the larger structures. For fractal branching to be significant, you must have more than just a primary and secondary branching. That is to say, no scientist would consider something to be a fractal if it occurs over less than an order of magnitude.

Rivers are a different story. Stream networks are fractal by several different measures. However, in line with the details of the question it's important to note
the poster asked about water forming a root like structure. The fractality of river networks is a pattern embedded within the earths surface, yes by the action of water, but water alone is not responsible for the network structure. To oversimplify, it's a sediment transport phenomenon, the flow is multi-phase (water + sediment), and therefore this is not just a water-only phenomenon.


Could Australia's bushfires aerosols actually decrease global temperature? Given the vastness and intensity of the bushfires that have been going on in Australia for weeks now, to the point they are generating their own weather and having an impact thousands kilometers away from their origin, an analogy with volcanic eruptions spurred to my mind and I wondered: could the net effect of these bushfires actually be a measurable cooling down of global temperature, as it happened with Mount Pinatubo, at least in the short term?

Well, the amount and intensity of wild fires are a direct outcome of global warming, that's not really news.

According to this article that cites a work i can't find, until the mid of December 2019 the Australian fires emitted ~250million tons of carbon, ~50% of Australia's yearly production. A recovery in the coming decades is unlikely, because the ecosystem is already compromised. It is "too optimistic" to assume that the forests will regrow and they will "never end up accumulating as much carbon as they had before". Instead, large areas of burning forests must more and more be seen as a biospheric component that can turn from a carbon sink to a source.

Here's an example (sorry paywalled, but the abstract has the interesting points and it is peer reviewed) for boreal forest fires, where fires can lead from net accumulation over several fire events to a net loss, leading to a positive feedback. A similar process is expected for the Amazon rain forest fires.

To the question: an exact answer seems to be difficult. It depends on how much aerosols end up where in the atmosphere and stays for how long. The effect can be modelled: Here, a fire aerosol laiden atmosphere's lower 6km can be warmed because they become a heat trap. The trap is caused because aerosols have a stabilizing effect on the upper atmosphere. A forest fire's plume has a different composition than a volcanic eruption !

This paper describes a similar effect, the absorption of solar radiation by carbon can heat the atmosphere.

I am aware that there may be other effects, inclduing atmospheric cooling, but i leave that part to somebody else. All in all, the negative effects of carbon release and the potential loss of regenerative abilities of the biosphere - because of drought, erosion, loss of biodiversity and the ecosystem, soil sterilization, invasive organisms as well as the difficulties to respond in time because of the sheer area affected by fire (all depending on intensity, duration and area) - by far outweigh any cooling effects of wild fires.

It is unlikely that the Australian fires will produce enough particulates by themselves to induce measurable global dimming, but we can't be sure because the fires are not yet finished and could continue for months. Another thing to remember is that Australia is not the only country to have major wildfires, so it seems probable that the combined effects of all these fires on global dimming may be measurable.

People worried about all the CO2 being poured into the atmosphere by these wildfires
should bear in mind that if the drought is followed by a wet period,the forest will regenerate and recapture an amount of CO2 equivalent to the amount they have released. Major eruptions like Pinatubo release colossal amounts of CO2, but unlike burning forests have no mechanism whereby they can suck most of it back in the fulness of time. They also release vast quantities of dust particles high into the atmosphere, accompanied by large amounts of sulphur dioxide which reflects solar radiation back into space, so that explains the cooling effect such major eruptions have. It usually doesn't last very long.


estimation of prehistoric sea levels From what reference point/level are prehistorical (e.g., Precambrian era) sea levels estimated?  As I understand things, the following are true:

Since the formation of continents, land elevations everywhere have been continually changing due to plate tectonics, weathering, sedimentation, etc.
The total volume of ocean water has been essentially the same since formation in the early Hadean.
Water seeks its own level.

So is the rise and fall of sea level derived from the geological record measured relative to the adjacent land, or the center of the earth, or what?

Short answer:    Nobody knows.   Estimates of post-cambrian water levels are done by studying geology and where shorelines were in the past and what land was under water and working out from that how high the sea level probably was.   There are no pre-cambrian sea level estimates that I know of.

Working out how much water was on the surface of the Earth, especially during the pre-Cambrian era is a difficult subject with much uncertainty.   While the total amount of water on Earth may not have changed too much too much over the last 3 billion years, ground water vs surface water, and the shape of the ocean basin and the role of volcanoes and tectonics add to the uncertainty.   There's still some uncertainty on snowball Earth and if it went all the way down to the equator over the oceans.   Sea level over the pre-cambrian requires working out the specifics of snowball earth.   It's a tricky subject full of uncertainty.

Long answer that also says we basically don't know:

  From what reference point/level are prehistorical (e.g., Precambrian
  era) sea levels estimated?

I've never seen a pre-cambrian era estimate on sea level so I don't know how they are estimated.   This is the oldest I could find.

As the article explains, historic sea level is estimated by finding where the shorelines were at geologically historic time periods and looking at what was under water.   There's probably a pretty significant margin of error in those estimates I would think.

The article also says

  The main factors affecting sea level are the amount and volume of
  available water and the shape and volume of the ocean basins. The
  primary influences on water volume are the temperature of the
  seawater, which affects density, and the amounts of water retained in
  other reservoirs like rivers, aquifers, lakes, glaciers, polar ice
  caps and sea ice. Over geological timescales, changes in the shape of
  the oceanic basins and in land/sea distribution affect sea level. In
  addition to eustatic changes, local changes in sea level are caused by
  tectonic uplift and subsidence.

  Over geologic time sea level has fluctuated by hundreds of meters.
  Today's interglacial level is near historic highs and is 130 meters
  above the low level reached during the Last Glacial Maximum
  19,000–20,000 years ago.

So, key factors are obviously ice ages and glaciers, as well as the shape of the ocean basin.   The movement of continents affects the shape and depth of the ocean basin, so continental movement likely has an effect.

As a somewhat small but fun example, the Mediterranean Sea has about 3.75 million cubic km of water in it and the sea is thought to have been a dry valley some 5.33 million years ago that, once the straight of Gibraltar gave way, was quickly filled by the Atlantic ocean.   That's just a theory.  It may have filled much more slowly, and over 5 million years ago, it might have been a significantly different size too, but if we use the 3.75 million cubic km number over today's 361.9 million square km of ocean surface, that works out to a 10 meter drop in sea level to fill up the Mediterranean valley.    10 meters isn't a big change in the grand scheme of things, but if it happened over as little as a year, as one hypotheses suggests, that would have been quite something to observe a 10 meter drop in sea level over a single year or so.   However long the Mediterranean took to fill, it's a nice example of how shifting land can affect sea level.

Historic estimates are made (as noted above) by studying where the shorelines were and studying what was under water and trying to piece together an estimate from that.   Formation of glaciers like the Antarctic Glacier, which would raise sea level 58 meters if it melted, affect sea level too.  The antarctic glacier began to grow in earnest about 34 million years ago.   Greenland is another 6 meters and that formed much later, over the last million years or so.

Geological history of ice ages is fairly well understood, though the total amount of water in those glaciers might have some uncertainty.   The shape of the ocean basin is (I think) less well understood over the last 600 million years or so.

The ice age periods, 260 to 360 and 420 to 450 million years ago should correspond to drops in the chart, below.  The recent ice age period is just 2.5 million years long, and too short to be well represented but the 34 million years when the antarctic ice formed is apparent.

  Since the formation of continents, land elevations everywhere have
  been continually changing due to plate tectonics, weathering,
  sedimentation, etc.

The continents formed quite early, between 2.5 and 3 billion years ago.  The silicate rock that form most of the granite that makes up both the continents and the continental plates was present at the formation of the Earth.   Heat and plate tectonics likely helped form the continents.   Life and photosynthesis may have added to them over time, but most of the continental material was present at Earth's formation.

Precisely how sea levels change, other than by formation of glaciers or the forming of filling of valleys on land is (to my knowledge) not well understood though the shape of the ocean basin (noted above) plays a key role.   The continents are roughly some 35 miles thick in silicate rock, but that far below the Earth's surface, silicate rock can melt and mix with basalt in the upper mantle.   We know this because lava can be either basalt rich or silicate rich.

Wikipedia mentions sediment and groundwater likely also play roles.  Over long enough periods of time, the rock cycle likely returns sediment that erodes of land into the ocean, back to the land.   Likewise, life can lead to the formation of limestone and other carbonate rock, but that's probably a small percentage of total land and a small factor, not a major factor.

The internal heat of the Earth (I would guess) play a bigger role.  A hotter earth, the upper mantle is a little closer to the surface and the granite continents and continental plates are less thick, so they float less high on the basalt, leading to a corresponding higher sea level, but that's just speculation on my part.   As Earth cools over hundreds of millions of years, the granite may become thicker and the sea level could drop in relation to the rising land.  This fits with the studies that sea level was generally higher in the past, but, again, this is speculation on my part.

  The total volume of ocean water has been essentially the same since
  formation in the early Hadean.

You probably shouldn't make that assumption.  The Hadean was the first epoch all the way back to the formation of the Earth.   For consistent amounts of water, the earliest I would consider starting would be the end of the late heavy bombardment, about 3.8 billion years ago.   That would be enough time for the magnetic field to form (about 4 billion years ago) and time for the sun to settle down, because UV rays from the young sun can strip water form Earth by photo-chemical dissociation.

Throughout the history of Earth, UV rays from the sun have stripped hydrogen from atmospheric water vapor, effectively taking water away from Earth and replacing it with hydroxide, which is fairly reactive.   Likewise, comets and asteroids that hit the Earth bring water with them.   The current rate is quite small and insignificant, but 3.8 billion years ago, even after the late heavy bombardment, there might still have been frequent enough comet impacts to affect sea level over different eras.

Precise numbers aren't known - question on that here.   But if Earth loses 50,000 tons of mass per year, most of that hydrogen stripped from water, that's as much as 900,000 tons of water photo-disintegrated per year.   Over a billion years, that's 900 trillion tons of water, which sounds like a lot, but it's less than 1/10th of 1% of our ocean's mass of about 1.5 million trillion tons.

That said, when the Earth was hotter when it was young, it could have had more water in it's upper atmosphere and lost more water than 0.1% per billion years.   This estimate suggests that the Earth lost as much as 25% of it's water over the last 3.8 billion years based on studying deuterium ratio in 3.8 million year old rocks to water on Earth today.

There's also the problem of water emerging from inside the Earth.   It was recently discovered that the lower mantle is wet and there's as much water deep inside the Earth as there is in the oceans, maybe more.   How much mantle water made it's way to the surface of the Earth during the pre-cambrian era is unknown.  Some of Earth's water today likely came from inside, even though the heat of formation of the planet probably lost most of it, some (at least an ocean's worth) is still deep inside the Earth but much (most?) is thought to have come from comets and meteors during the late heavy bombardment.

  So is the rise and fall of sea level derived from the geological
  record measured relative to the adjacent land, or the center of the
  earth, or what?

Speaking strictly for the geological record, it's not directly measured, but estimated by the methods discussed above, looking at geological records of old shorelines and land that was once under water and working out an estimate.

Sea level from the center of the Earth is mostly done for modern measurements.   You can measure sea level against the land, but land can rise and fall, or it can be measured from the center of the Earth, independent of land shifting.   I don't think that's particularly relevant to your question on geological estimates of sea level.

That probably needs some cleaning up, but it's a fun subject.   I thought I'd give it a shot.

First there are many ways of estimating sea level, you will have to examine a specific paper to see what they use. As a rule of thumb global sea level is usually measured relative to current sea level in paleoclimate studies this is confusingly an absolute measure, usually eustatic (volume of the ocean water). Keep in mind sea level is different across the planet's surface when measured from the center of the planet thanks to spin and gravity anomalies so there is no absolute measure of height, so instead volume is used. There are of course many relative measures of sea level but this is more referring to sea depth than anything else and thus are local effects.

Second if you haven't guessed, the volume of the ocean is not constant it changes quite a bit, both the volume of the water and the volume being occupied, the volume of the container if you will. The mass is more constant (on the scale being measured) but even then influenced by removing or adding water. Many measures of sea level are eustatic, meaning they are measuring change in the volume of the ocean.

On the global level there are two big issues influencing sea level, temperature and available water(mostly ice caps).

The temprature has a big effect due to thermal expansion, change the temprature and the volume of water changes even if the mass is the same. Most of the our current sea level rise is due to thermal expansion not melting glaciers.

The second is if there are ice caps and how big they are, since ice frozen on land is not in the ocean. The earth right now  basically has only one ice cap (antarctica). Icecaps are largely controlled by whether their are continents near the poles. Isolated dry basins that flood can have a similar effect by increasing the area that needs to be filled, for instance when the mediterranean flooded it is estimated to have dropped global sea level (of the rest of the ocean) by ~ 9 meters in a about a year or two, which may be one of the most dramatic change in history, and probably scared the crap out of the humans around at the time. The drop is caused by increasing the volume being filled without changing the volume of water.

There are lots of smaller and/or local effects that can change sea level or local sea level and wiki has a decent chart of them here, these include age of the oceanic plates, plate rebound, and intercontinental reservoirs.