Climate Change 2

Goo: . So, I think we need to think a little bit more about the dynamics of power solar radiation affects the earth. . Does UV penetrate sea water?

Kinkajou:. The key factor likely to cause more warming is actually that there is increased heat penetrance into the earth’s surface. The earth’s surface is two thirds ocean. So even having small extra amounts of energy being retained by the ocean, can cause substantial heating effects or climate change effects on our planet – earth. And if the ocean is even infinitesimally warmer, you will be getting ice melting , then amplified by albedo changes.

Some models have suggested that TSI variation has little effect on global warming/global climate change. However, other scientists have disagreed.

Recent findings indicate that intrinsic TSI variation has had a much larger role (up to 50%) in global warming during the industrial era than previously predicted by global circulation models (GCM’s).

Erasmus: . Water scatters but does not absorb ultraviolet light. It absorbs infrared light quickly – little infrared light penetrates more than 2 meters into seawater. Visible Light is also quenched rather quickly even in clear water. Only about 25 percent of incident light reaches a depth of 10 meters in the open ocean, where water is very clear, (not turbid as in shallow coastal or river areas).

Most Frequencies of Solar Radiation especially the solar frequencies required for photosynthesis are rapidly absorbed in water and have a very low penetration.

How deep does UV penetrate into the ocean?

Sunlight (UV predominantly) entering the water may travel about 1,000 meters deep into the ocean under the right conditions, but there is rarely ANY significant light beyond 200 meters. So, an increase in UV causes a disproportionate heating of the earth’s oceans then would visible light due to its penetrance.

Kinkajou:. The graph below is important because it highlights that solar cycles do make a difference to the amount of UV that penetrates to the earth’s surface. The two dashed lines highlight the difference between the amount of solar radiation of frequency between 10 Å and 1000 Å that is received on planet Earth at solar maximum versus solar minimum. Many of these wavelengths are absorbed by the ionosphere – which it is responsible for creating. The longer wavelengths of light (heat or infrared) are much more constant and essentially do not vary with the solar cycle.

The amount of radiation reaching the ground also depends on factors such as whether the Sun is close to overhead in the sky, and conditions in the atmosphere such as the concentration of ozone.

Solar Radiation Spectrum

Erasmus: . This Ultraviolet wavelength

UVA – Long-wavelength UVA covers the range 315–400 nm. It is not significantly filtered by the atmosphere. UV-A comprises about approximately 90% of UV radiation reaching the Earth's surface. UVA is again divided into UVA-I (340 nm - 400 nm) and UVA-II (315 nm - 340 nm).

UVB – Medium-wavelength UVB covers the range 280–315 nm.
Note it is the UV-A with the highest penetrance of our atmosphere / oceans.

UV Absorption

Kinkajou:. Looking at the above graph, what is DU in the ozone layer?

Erasmus: . The Dobson unit (DU) is a unit of measurement of the amount of a trace gas in a vertical column through the Earth's atmosphere. The Dobson Unit is still primarily used to describe how much ozone there would be in the column if it were all squeezed into a single layer. The average amount of ozone in the atmosphere is roughly 300 Dobson Units. The majority of this resides within the stratospheric ozone layer.

Dobson Unit

Erasmus: . The DU (Dobson unit), is defined as the thickness (in units of 10 microns) of that layer of pure gas which would be formed by the total column amount at standard conditions for temperature and pressure (STP). A typical column amount of 300 DU of atmospheric ozone therefore would form a 3 mm layer of pure gas at the surface of the Earth if its temperature and pressure conformed to STP. (standard temperature and pressure).

NASA uses a baseline value of 220 DU for ozone. This was chosen as the starting point for observations of the Antarctic ozone hole, since values of less than 220 Dobson units were not found before 1979.We have inferred, from direct measurements over Antarctica, a column ozone level of less than 220 Dobson units is a result of the ozone loss from chlorine and bromine compounds

Spectral Distribution of Solar Radiation

The graph below shows the amount of radiation produced by the Sun over the range spanning from the extreme ultraviolet, through the ultraviolet, visible and into the infra-red.

Solar Energy Distribution

The distribution of radiation can be divided into two regions. Above a wavelength of around 1000 Angstroms (solid curve) the radiation produced by the Sun is 'thermal' in origin - i.e., it arises because the Sun is a hot object. The spectral distribution has a shape known as a black body curve with the peak occurring at around 5000 Angstroms - in the middle of the range of wavelengths which we are able to see. For higher, or lower, wavelengths the radiation produced by the Sun decreases.

Within this range, the region from around 1000 Angstroms up to around 4000 Angstroms is the ultraviolet and this radiation much of this is absorbed in the atmosphere of the Earth by the ozone layer. Look at the graph below to assess the degree of UV penetrance into our atmosphere.

Solar Energy and the Ocean

The graph is representative of sunlight hitting the earth as a whole. This is why it shows the atmosphere taking  a lot more than an 18% bite out of sunlight.  In the morning and afternoon sunlight passes through more atmosphere before it hits the ground and higher latitudes have a similar effect.

As you can see in the UV column, the atmosphere stops about half the ultraviolet light at some frequencies , mostly due to the ozone layer,  Moving to the right, more than one quarter of visible light is lost and then the atmosphere takes some big bites out of infrared.  The big pieces missing from the red are the result of gases in the atmosphere absorbing specific bands of sunlight energy before it hits the ground.

Kinkajou:. So, we can see here that a one percent increase in UV-A would be equivalent to a 2% increase in energy and a proportionately greater increased penetration of energy in a situation with lowered Ozone.

As we have stated, Recent findings indicate that intrinsic TSI variation has had a much larger role (up to 50%) in global warming during the industrial era than previously predicted by global circulation models (GCM’s).

Emission Spectra Halide Light

Kinkajou:. Let’s look at the of an Emission Spectrum of a Halide Lamp
and of various complex atoms.

The iron-group elements have complex spectra with thousands of lines from the VUV to the infrared
Lines from FeII in particular account for as many as half of the absorption features in A- and late B-type stars in all wavelength regions They also form prominent emission lines from a wide variety of stellar objects including chromospheres of cool stars active galactic nuclei and nebular regions around massive stars.

Problems in modeling stellar spectra in the UV and VUV often can be traced to the lack of adequate data for iron-group elements, particularly for very highly excited levels of these elements.

Emission Spectra of Large Atoms

Emission Spectra

Emission Spectra

Note the greater number of "purple" bands / emission lines in the more complex or heavier atoms.

Erasmus: . You can see from the above example the extent of the emission spectra of complex atoms in the UV range.

Goo: . So, let’s talk a little bit more about the sunlight or solar radiance that hits the earth.

Erasmus: . Sunlight On Earth
By the time sunlight energy reaches the top of earth’s atmosphere its intensity will be around 1,366 watts per square meter.  Passing through the atmosphere will reduce that by 18% down to 1,120 watts- that’s 1,120 watts at noon, at the equator, on a clear day.

Kinkajou:. So, tell us something about the meteorites that could be used to create a fluorescent solar gas.

Erasmus: . There are three main groups of meteorites. They differ in their amount of iron-nickel metal
* iron meteorites: .. They consist mainly of iron-nickel metal with small amounts of sulphide and carbide minerals. Iron meteorites are mainly made of an iron-nickel alloy with a distinctive crystalline structure known as a Widmanstätten texture. Bands are formed by varying levels of nickel.

Iron Meteorite: Iron meteorite showing dark fusion crust

* stony-iron meteorites: which have nearly equal amounts of metal and silicate crystals.

There are two different types of stony-iron meteorites: pallasite and mesosiderite.

Pallasites contain big, olive-green crystals - a form of magnesium-iron silicate called olivine - embedded entirely in metal either as crystals or as a pattern of veins through the solid metal of the meteorite.

Mesosiderites.
Mesosiderite meteorites are breccias, a variety of rock composed of broken fragments of minerals or rock cemented together by a finer material. The fragments contain a mix of igneous (solidified) silicate and metal clasts (rocks made of pieces of older rocks).
Mesosiderites form when debris from a collision between two asteroids is mixed together. In the crash, molten metal mixes together with solid fragments of silicate rocks

Each group can be split into many more classes and types depending on the minerals, structure and chemistry.

Polished cut Slab of Pallasite Meteorite:
A cut and polished slab of the pallasite Imilac meteorite 

* Stony meteorites
The majority of meteorite finds are stony meteorites, consisting mostly of silicate minerals.
There are two main types of stony meteorite: chondrites (some of the oldest materials in the solar system) and achondrites (including meteorites from asteroids, Mars and the Moon).

Both chondrites and achondrites have many subgroups based on their compositions, structures and the minerals they contain.

At over 4.5 billion years old, chondrites are some of the most primitive and pristine rocks in the solar system and have never been melted.

Chondrites have a distinctive appearance, made from droplets of silicate minerals mixed with small grains of sulphides and iron-nickel metal. Their millimetre-sized granules give chondrites their name, from the Greek 'chondres' meaning sand grains.

There are many varieties of chondrite, with differences in mineralogy relating to the type of asteroid the meteorite came from.

Chondrites are the material from which the solar system planets formed.

Chondrite Meteorite:  A cut slab of chondrite meteorite

Kinkajou:. I think the key issue is that meteorites contain complex atoms such as silica and iron which would fluoresce if excited, substantially more in the UV spectrum then other simpler atoms.

Goo: . So just how much variation in climate has of there being in Earth’s history.

Erasmus: . I think the earth itself provides a good historical record of its own climate change.
Global sea level rose by a total of more than 120 metres as the vast ice sheets of the last Ice Age melted back. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 metre per century.

Kinkajou:. What do you think about the CO2 story.

Erasmus: .
CO2 Concentration Changes Do Not Drive Sea Levels.

Post Glacial Sea Level rise

From about 7000 years ago to 2000 years ago, or from the Mid- to Late-Holocene, atmospheric CO2 concentrations varied between only about 260 and 270 parts per million, or ppm.

Today’s levels, have eclipsed 400 ppm in recent years.  These high CO2 concentrations are believed to cause dangerous warming, rapid glacier melt, and catastrophic sea level rise.

And yet, despite the surge in anthropogenic CO2 emissions and atmospheric CO2 since the 20th century began, the UN’s Intergovernmental Panel on Climate Change (IPCC) has concluded that global sea levels only rose by 1.7 mm/yr. during the entire 1901-2010 period, which is a rate of less than 7 inches (17 cm) per century.   A new paper even suggests the global trend is better represented as closer to 1.3 mm/yr., or about 5 inches per century:

According to Wenzel and Schröter (2014), the acceleration rate for the sea level rise trend since 1900 has been just +0.0042 mm/yr., which is acknowledged by the authors to be “not significant” and well within the range of uncertainty (+ or – 0.0092 mm/yr.)- to put the overall 20th/21st century sea level rise acceleration rate at probably at  zero.

Further complicating the paradigm that contends changes in CO2 concentrations drive sea levels is the fact that ice core evidence affirms CO2 levels remained remarkably constant (fluctuating around 255 to 260 ppm) during the same period that there was an explosively fast rate of sea level rise — between 1 and 2 meters per century (about 10 times today’s rates) — between 12,000 to 8,000 years ago.    Sea levels rose by ~60 meters during those 4,000 years while CO2 levels effectively remained constant.

And casting even more doubt on the assertion that variations in CO2 drive sea level rise is the fact that there is robust paleoclimate evidence to suggest that today’s mean sea levels as well as today’s sea level rise rates are both relatively low (from a historical standpoint) and also well within the range of natural variability.  

Nothing unusual is happening to sea levels today.  For even though we have evidence that modern CO2 concentrations (~405 ppm) are historically high relative to the last 10,000 years, we also possess a growing body of evidence that modern sea levels are still about 1 to 2 meters lower than they have been for most of the last 7,000 years.

The fundamental problem for the CO2-rise-causes-sea-level-rise paradigm, then, is that rising CO2 concentrations have not been correlated with rising sea levels for nearly all of the last 12,000 years.  

In fact, the opposite has been observed during the last 2,000 years, or during the Late Holocene: CO2 levels have risen (gradually, then rapidly) while sea levels have fallen overall, with recent changes so modest (inches per century) that they do not override the overall trend.

  In the 8,000 years before that, sea levels rose rapidly while CO2 concentrations remained flat.  Simply put, the supposed anthropogenic “signal” in sea level rise trends has largely gone undetected — a point that has been progressively affirmed by increasing numbers of climate scientists.

in general, the data indicate a marked slowdown between 7 and 8 kyr BP ( before present), with sea level rising steadily to form a high point of ~2-4 m [above present sea level] between 6 to 4 kyr BP [6000 to 4000 years before present]. This is followed by a steady fall, reaching present day levels by ~1 kyr BP.

Relative Sea Levels

https://notrickszone.com/2017/02/06/35-scientific-papers-global-sea-levels-were-1-2-meters-higher-than-now-for-most-of-the-last-7000-years/

So, CO2 isn’t the only thing that changes sea levels, but all other things staying equal it would be the only thing (through increased warming of the surface).

Kinkajou:. The issue that emerges for me is that our models have to deal with a lot of complexity and variability. And this means that there are always assumptions made. So, it is not surprising that there is considerable disagreement as to what the data predicts.

Carbon dioxide is not a good explanation for the warming events of the last 15,000 years. The major variable contends to be TSI or total solar irradiance. Recent findings indicate that intrinsic TSI variation has had a much larger role (up to 50%) in global warming during the industrial era than previously predicted by global circulation models (GCM’s).

Goo: . But who is right?

Dr Axxxx: .  Humanity only has an early appreciation of solar dynamics and climate modeling It is trying to make sensible decisions but based on some primitive modeling and very arguable assumptions. But it is likely that there are others who have a much greater appreciation of how it all works.
Erasmus: . I can see you are talking about the aliens – or at least the ones who have secretly embedded themselves within our world. We can only hope- not to our detriment. But this hope that that they may not act to our detriment may well be a forlorn hope.

Relative Sea Level

Kinkajou:. Are we heading into a new Ice Age?

Erasmus: . What The Science Says:
The warming effect from more CO2 greatly outstrips the influence from changes in the Earth's orbit or solar activity, even if solar levels were to drop to Maunder Minimum levels. Or so say some scientists.

Other scientists have different views. Notably, Recent findings indicate that intrinsic TSI variation has had a much larger role (up to 50%) in global warming during the industrial era than previously predicted by global circulation models (GCM’s).

So, I think it becomes a little difficult to know who to believe.

Just a few centuries ago, the planet experienced a mild ice age, quaintly dubbed the Little Ice Age. Part of the Little Ice Age coincided with a period of low solar activity termed the Maunder Minimum (named after astronomer Edward Maunder).

Solar Activity Historically by C14 Assays

It's believed that a combination of lower solar output and high volcanic activity were major contributors, with changes in ocean circulation also having an effect on European temperatures . 

Total Solar Irradiance (TSI). TSI from 1880 to 1978 from Solanki. TSI from 1979 to 2009 from Physikalisch-Meteorologisches Observatorium Davos (PMOD). 

Solar Activity History

Kinkajou:. Could we be heading into another Maunder Minimum?
Erasmus: . Solar activity is currently showing a long-term cooling trend, now.(1950-2000).

The current trend says that we are within a sunspot cycle approaching solar max in 2022- 2023.

2009 saw solar output at its lowest level for most of a century. However, solar output levels have generally increased since the Maunder Minimum.

However, predicting future solar activity is problematic.
Let's say for the sake of argument that the sun does enter another Maunder Minimum over the 21st century. What effect would this have on Earth's climate?

Simulations of the climate response if the sun did fall to Maunder Minimum levels suggest that the decrease in temperature from the sun is minimal compared to the warming from man-made greenhouse gases .

Dr Axxxx: . Depends on the model and the assumptions.
Erasmus: . . True. Our models are basis for more disagreement than agreement.

The CO2 model says:
Cooling from the lowered solar output is estimated at around 0.1°C (with a maximum possible value of 0.3°C) while the greenhouse gas warming will be around 3.7°C to 4.5°C, depending on how much CO2 we emit throughout the 21st century. However not everyone agrees with this prediction.

Again, we make the point: Recent findings indicate that intrinsic TSI variation has had a much larger role (up to 50%) in global warming during the industrial era than previously predicted by global circulation models (GCM’s).

Kinkajou:. Carbon dioxide is blamed for a substantial amount of global warming/climate change and this may well be correct. The problem is that TSI does not vary a great deal and it seems counterintuitive to believe that a 0.1% change in TSI can really be responsible for climate change.

I suppose the key observation is that temperature change or climate change is a progressive event. Small changes in temperature cause small amounts of ice melting , changing albedo and creating positive feedback for temperature change.

Goo: . The situation is certainly not straightforward and is open to much argument and discussion.

Erasmus: . However, our climate has experienced much more dramatic change than the Little Ice Age. Over the past 400,000 years, the planet has experienced ice age conditions, punctuated every 100,000 years or so by brief warm intervals.
These warm periods, called interglacials, typically last around 10,000 years. Our current interglacial began around 11,000 years ago.

Kinkajou:. Could we be on the brink of the end of our interglacial?

Earth's Temperature over Last 420,000 years:
Temperature change at Vostok, Antarctica .
Interglacial periods are marked with purple dots - above.

Erasmus: .

The Figure below examines the climate response to various CO2 emission scenarios.

The purple line is the natural response without CO2 emissions. 
Light Blue represents an anthropogenic release of 300 gigatonnes of carbon - we have already passed this mark.

Release of 1000 gigatonnes of carbon (light green line) would prevent an ice age for 130,000 years.
If anthropogenic carbon release were 5000 gigatonnes or more, glaciation will be avoided for at least half a million years.

As things stand now, the combination of relatively weak irradiative forcing and the long atmospheric lifetime of carbon dioxide is likely to generate a longer interglacial period than has been seen in the last 2.6 million years.

Earth's Temperature and its relation to CO2 Emissions

Effect of fossil fuel CO2 on the future evolution of global mean temperature. Purple represents natural evolution,light blue represents the results of anthropogenic release of 300 Gton C, light green 1 is 1000 Gton C, and light green 2 is 5000 Gton Carbon.

Goo: . Currently the Arctic permafrost is degrading, Arctic Sea ice is melting and the Greenland ice sheet is losing mass at an accelerating rate. These hardly suggest that an ice age is imminent.

They do confirm that the earth is warming, but humans are making some big assumptions blaming CO2 and forgetting about solar irradiation/ solar forcing.

Goo: . Tell us about Sunspots

Erasmus: . The Sun's apparent surface, the photosphere, radiates more actively when there are more sunspots.
Satellite monitoring of solar luminosity reveals a direct relationship between the solar cycle and luminosity with a peak-to-peak amplitude of about 0.1%.

 Luminosity decreases by as much as 0.3% on a 10-day timescale (short-term) when large groups of sunspots rotate across the Earth's view and increase by as much as 0.05% for up to 6 months(medium term) due to faculae associated with large sunspot groups.

Solar faculae are bright spots in the photosphere that form in the canyons between solar granules, short-lived convection cells several thousand kilometres across that constantly form and dissipate over timescales of several minutes.

Faculae are produced by concentrations of magnetic field lines. Strong concentrations of faculae appear in solar activity, with or without sunspots. The faculae and the sunspots contribute noticeably to variations in the "Solar Constant”-– the total solar energy output. The chromospheric counterpart of a facular region is called a plage.

The best information today comes from SOHO (a cooperative project of the European Space Agency and NASA), such as the MDI magnetogram, where the solar "surface" magnetic field can be seen.

As each cycle begins, sunspots appear at mid-latitudes, and then move closer and closer to the equator until a solar minimum is reached. This pattern is best visualized in the form of the so-called butterfly diagram. Images of the Sun are divided into latitudinal strips, and the monthly-averaged fractional surface of sunspots is calculated. This is plotted vertically as a color-coded bar, and the process is repeated month after month to produce this time-series diagram.

The sunspot butterfly diagram.

Time vs. solar latitude diagram of the radial component of the solar magnetic field, averaged over successive solar rotation. The "butterfly" signature of sunspots is clearly visible at low latitudes.

Erasmus: .

An overview of three solar cycles shows the relationship between the solar cycle, galactic cosmic rays, and the state of Earth's near-space environment.

In considering climate change, we can look a long way back in history if we look at carbon-14 and beryllium-10  isotopes. These form when solar sourced cosmic rays collide with atmospheric particles and subsequently become stored in terrestrial reservoirs such as ice sheets and tree rings.

Such reconstructions indicate that the overall level of solar activity since the middle of the twentieth century stands amongst the highest of the past 10,000 years, and that epochs of suppressed activity, of varying durations have occurred repeatedly over that time span.

Reconstruction of solar activity over 11,400 years.
Sunspot numbers over the past 11,400 years have been reconstructed using carbon-14 isotope ratios.
The level of solar activity beginning in the 1940s is exceptional – the last period of similar magnitude occurred around 9,000 years ago (during the warm Boreal period). The Sun was at a similarly high level of magnetic activity for only ~10% of the past 11,400 years. Almost all earlier high-activity periods were shorter than the present episode.

Fossil records suggest that the Solar cycle has been very stable for at least the last 700 million years.

The data suggest that there may be other solar cycles besides the 11-year sunspot cycle as well.

Waldmeier effect
The Waldmeier effect describes the observation that the maximum amplitudes of solar cycles are inversely proportional to the time between their solar minima and maxima. Therefore, cycles with larger maximum amplitudes tend to take less time to reach their maxima than cycles with smaller amplitudes.

Gleissberg cycle
The Gleissberg cycle describes an amplitude modulation of solar cycles with a period of about 70–100 years, or seven or eight solar cycles.

Other hypothesized cycles do exist but we can only guess as to their activity / importance with our only recent knowledge of science and solar radiation.

2,300-year Hallstatt solar variation cycles.

Dr Axxxx: .  As we have stated, humanity is only at the early stages of looking at solar science. And it has only really had one sun to look at intensively – its own. I believe others have greater experience and knowledge of how it all works and how it can all be manipulated.

Goo: . Chilling!