The EUV spectrum of the Sun: Irradiances during 1998–2014
G. Del Zanna 1 and V. Andretta 2
A&A 584, A29 (2015)
DOI: 10.1051/0004-6361/201526804
(c) ESO 2015
Open access on registration
Examples from paper Fig 6
From abstract
… show that the irradiances in the hot (2–3 MK) lines are significantly
lower for the cycle 24 maximum compared to the previous one.
From Introduction
1. Introduction
The present paper is part of an on-going effort to provide the
best possible solar spectral irradiance in the extreme ultraviolet
(EUV). The solar EUV variability causes dramatic changes in
the temperature and density of the thermosphere, and it could
also have some indirect effects on the climate. Indeed, some of
the current global circulation models also require EUV irradi-
ances to properly take the solar forcing into account.
The work is about correcting for known satellite instrument degradation.
Post by Tim
Thanks for sharing the link.
EUV alters the earth’s magnetic field causing changes in compass declination that have been well known for centuries (summarizing Lief Svalgaard). EUV measurements from the SOHO spacecraft some 1.5m km out at a particularly serendipitous position between the earth and the sun since 1996 and remarkably equal measurements of the EUV proxy 10.7 microwave flux on earth scale with convincing fidelity to the SQRT of sunspot area. Why would this be? Are we seeing the reciprocal of MC^2? And with no detectable erosion of the signal between the spacecraft afar and the surface despite having created ionospheric winds and tweaking declination (QBO?) Sum Ding Dontadduphere.
Conclusions
• The thermosphere/ionosphere system was indeed cooler, less dense, and lower,
during the minimum of solar cycle 23/24 than during a “typical” solar minimum.
• The primary cause of this was lower than “usual” solar EUV irradiance.
• The Mg II core-to-wing ratio variations are consistent with these observations.
• Secular change due to increasing CO2 makes a small but significant contribution.
• Lower geomagnetic activity during 2008-2009 also makes a small but significant
contribution.
• Work in progress extends this modeling effort to possible ionospheric changes.
Click to access Solomon.pdf
“Their work built on several recent studies. Earlier this year, a team of scientists from the Naval Research Laboratory and George Mason University, measuring changes in satellite drag, estimated that the density of the thermosphere declined between 2007 and 2009 to about 30 per cent less than during the previous solar minimum in 1996. Other studies by scientists at the University of Southern California and CU, using measurements from sub-orbital rocket flights and space-based instruments, have estimated that levels of extreme-ultraviolet radiation-a class of photons with extremely short wavelengths-dropped about 15 per cent during the same period.”
http://www.reportingclimatescience.com/this-issue/atmosphere-and-surface/solar-minima-results-in-thin-and-cool-thermosphere.html
These are good comments.
David Evans is saying a similar thing about solar energy at certain wavelengths being the key, not the TSI that the IPCC happily talks about because it doesn’t alter the manmade warming them.
See http://joannenova.com.au/2015/11/new-science-20-its-not-co2-so-what-is-the-main-cause-of-global-warming
If we could only get accurate readings on EUV. The Layman sunspot site was providing the readings but then the instrumentation got all off and it was curtailed.
I really liked having access to the EUV light unit of measurement readings when it was on Layman’s Sunspot Site.
SOLAR EUV IRRADIANCE
Solar Extreme Ultraviolet (EUV) is solar radiation that covers the wavelengths 10 – 120 nm of the electromagnetic spectrum. It is highly energetic and it is absorbed in the upper atmosphere, which not only heats the upper atmosphere but also ionizes it, creating the ionosphere. Solar EUV radiation changes by a factor of ten over the course of a typical solar cycle. This variability produces similar variations in the ionosphere and upper atmosphere. Solar EUV variations are one of the three primary drivers of ionospheric variability.
Solar Extreme-Ultraviolet (EUV) radiation originates in the corona and chromosphere of the Sun’s atmosphere. The solar EUV spectrum, between 1 and 120 nm, is dominated by spectral lines from hydrogen (H), helium (He), oxygen (O), sodium (Na), magnesium (Mg), silicon (Si), and iron (Fe). The EUV photons reach Earth and are completely absorbed in the upper atmosphere above 80 km. The thermosphere of the earth, 80 to 600 km in altitude, is heated predominantly by solar EUV radiation. The EUV photons also ionize the atmosphere creating electrons, which form the ionosphere. Solar EUV irradiance varies by as much as an order of magnitude on time scales of minutes to hours (solar flares), days to months (solar rotation), and years to decades (solar cycle). The highly varying EUV radiation causes the thermosphere and ionosphere to vary over similar magnitudes and time scales.
Because solar EUV radiation is absorbed by the upper atmosphere it is impossible to measure from the ground. Thus, measurements must be made from rockets and satellites. It is difficult to build and maintain sensors that can measure the solar EUV radiation so for many years people relied on proxies for solar EUV such as the Sunspot Number or the F10.7 cm radio flux.
http://www.swpc.noaa.gov/phenomena/solar-euv-irradiance
Yes, the sun’s wavelengths vis and above are the key. The really short wavelengths not only heat the upper atmosphere, they also cause chemical reactions like O2/O3 conversion and reactions with NOx. These in turn change atmospheric dynamics.
>>>>>>>>>>>>
A bit of the data collection I have done on the subject. (Useful for beating alarmist over the head.)
NASA has finally admitted that the sun is not constant and although the Total Solar Insolation is relatively constant the distribution of the energy among wavelengths is not.
NASA has also admitted different wavelengths of sunlight do different things in different parts of the atmosphere.
Solar Spectral Irradiance Data
Sunlight + oxygen (O2) ===> O + O
(Oxygen is disassociated in to two atoms and wants to glom onto something.)
O + O2 ====> O3 (ozone)
The reverse also happens in the atmosphere so the formation and destruction of ozone is dependent on the shifting of the amount of solar radiation at different wavelengths and NASA has shown those amounts DO SHIFT.
image from: (wwwDOT)oxidationsystems.com/products/ozone.html
OZONE CIRCULATION
CHARACTERISTICS OF THE GENERAL CIRCULATION OF THE ATMOSPHERE AND THE GLOBAL DISTRIBUTION OF TOTAL OZONE AS DETERMINED BY THE NIMBUS III SATELLITE INFRARED INTERFEROMETER SPECTROMETER
Changes in Ozone and Stratospheric Temperature
CONTINUED
Top-Down Solar Modulation of Climate: evidence for centennial-scale change
Then we get into the effect on the poles.
Quasi-biennial oscillation and solar cycle influences on winter Arctic total ozone
The influence of solar variability and the quasi-biennial oscillation on lower atmospheric temperatures and sea level pressure
Climate System Response to Stratospheric Ozone Depletion and Recovery
MORE:
Climate Change Look up, Look out
Basic Description
The Antarctic ozone hole: An update
The Antarctic Circumpolar Current is a wind driven current.
This is what I have found on the current and the winds that drive it:
Ozone intensification of the westerly winds connection. (You will need to hold your nose while reading it.) http://www.theozonehole.com/ozonehgood.htm
Measurements of ozone at the same site are given @ (wwwDOT)theozonehole.com/ozoneholehistory.htm
I think this paper has the tail wagging the dog. If they didn’t they would be saying the sun via ozone changes drives ENSO. However it is still the best paper I have come across so far.
It is a long paper (12 pages) so I have distilled parts of it:
So what we have for the solar driven climate is:
Change in Solar ==> change in ozone ==> change in Quasi-Biennial Ocillation (QBO) ==> Change in ozone at the poles ==> change in wind strength/patterns in the Antarctic ==> Change in the West Wind Drift (the wind driven Antarctic Circumpolar Current) ==>restriction at Drake Passage causes variable amounts of Antarctic cold water to run up the side of the coast of South America as the Humboldt Current ===> ENSO
Cold water also runs up the side of the coast of South Africa into the Atlantic and the amount would be controlled by the same wind pattern/strength. (The ENSO tele-connection to the Atlantic anyone?)
If you look at this Sea Surface Temperature map it has a good image of the tongue of cold water from the Antarctic Circumpolar Current just before Drake Passage, headed up the west coast of South America to Galapagos where El Nino forms. You can also see the tongue of cold water headed up the east coast of South America (Cape Horn Current) as well as the west coast of Africa.
“…The Cape Horn Current is a cold water current that flows west-to-east around Cape Horn. This current is caused by the intensification of the West Wind Drift as it rounds the cape….” — WIKI
Retired EPA scientist, F.H. Haynie said on January 18, 2014
DRAKE PASSAGE
Effect of Drake Passage on the global thermohaline circulation
Drake Passage and palaeoclimate
Research on Drakes Passage today:
Summer upper-layer Antarctic Circumpolar Current structure and transport in Drake Passage based on ship-born ADCP measurements
And saving the best for last:
Sunspots, the QBO, and the Stratosphere in the North Polar Region – 20 Years later Oct. 2005
So to put it all together.
NASA has found that although TSI stays relatively constant the ratio of short vs long wavelengths does not. This is important because of ozone formation and destruction. 240 nm = ozone formation and 320 nm = ozone destruction. Therefore a shift in the amount of solar energy at 320 nm vs 240 nm will change the amount of ozone.
Ozone is linked to many different changes in both the atmosphere and also, via changes of wind strength, in the Antarctic, the oceans and ENSO.
There are many other connections but that is one.
(Seems the earth’s magnetic field is weakening and that too changes ozone.)
Magnetic field changes, NOx and Ozone by James A. Marusek. Nuclear Physicist & Engineer. U.S. Department of the Navy, retired.
http://www.breadandbutterscience.com/OzoneHole.pdf
Awful lot of reading there Gail. 🙂
I hope that is useful as an archive.Vast amount on the Talkshop.
Gail Combs the magnetic field of the solar wind pushes the ozone over the poles, because ozone is diamagnetic.
Diamagnetic materials create an induced magnetic field in a direction opposite to an externally applied magnetic field, and are repelled by the applied magnetic field. In contrast, the opposite behavior is exhibited by paramagnetic materials. Diamagnetism is a quantum mechanical effect that occurs in all materials; when it is the only contribution to the magnetism the material is called a diamagnet. Unlike a ferromagnet, a diamagnet is not a permanent magnet.
” The Earth’s Magnetic Field and the
Magnetic Properties of Oxygen, Nitrogen
Oxides, Chlorine Atoms and Some
Chlorine Combinations and Ozone
Molecules
Many of the problems cited above can be overcome by
taking into account an effect which should be playing an
important role in the transport of gaseous substances
throughout the atmosphere. In the analysis of the data
made until the moment an important physical property of
gaseous molecules has not been considered. This property
is linked to the presence in the HOMO of the concerned
molecule of paired or unpaired electrons. In the
first case the corresponding molecules would be diamagnetic
in nature, whereas in the second instance they
would be paramagnetic. The diamagnetic molecules interact
with a magnetic field in such a way that they
would tend to be driven towards regions where the magnetic
field intensity is lower, unlike the paramagnetic
ones, which would be shifted towards places where the
magnetic field intensity is higher. Thus, for the case of
the Earth’s magnetic field, paramagnetic molecules
would be driven towards the poles where the magnetic
field presents maximum intensities, whereas diamagnetic
molecules would tend to be shifted from polar latitudes
towards equatorial ones.
A classification can be made of the gaseous substances
which participate in the chemical and photochemical
reactions of destruction of the ozone layer. Thus, paramagnetic
species are O2, NO, NO2, NO3, NOy, ClO, Cl,
whereas diamagnetic species are O3 and N2O.
The interaction between diamagnetic and paramagnetic
gas molecules with the Earth’s magnetic field can
contribute to a continuous flow of paramagnetic gases
towards the poles and of gases composed by diamagnetic
molecules equatorial- or tropical-wards. Therefore, according
to the classification made before of the magnetic
properties of different gaseous molecules present in the
atmosphere, O2, NO, NO2, NO3, NOy, ClO and Cl tend to
accumulate near the poles where they react with the O3
molecules through chemical (in the absence of photons)
or photochemical reactions, whenever the conditions are
adequate for it (low temperatures which allow the presence
of ice needles in suspension able to contribute to the
third body effect). Such an accumulation is in agreement
with the measured continuous decrease of the (O3/NOy)
ratio mentioned before. The destruction mechanism of
ozone is accompanied by the tendency of the ozone
molecules to be shifted by the magnetic field towards
equatorial latitudes, so that both effects can account for
the rapid degradation of the ozone layer observed during
the winter.”
file:///C:/Users/irek/Downloads/GSC20120300002_48387174.pdf
Gail, I know ren isn’t surprised by this, as he pointed out many times over the past several winters on many blogs regarding the real-time solar influence on ozone and the polar vortex:
“Effects of solar variability related to the 11-year sunspot cycle are most obvious in the stratosphere, though still not fully understood (Crooks and Gray, 2005; Matthes et al., 2006).
Labitzke suggested in 1982 that the Sun influences the intensity of the north polar vortex (i.e., the Arctic Oscillation (AO)) in the stratosphere in winter, and that the Quasi-Biennial Oscillation (QBO) is needed to identify the solar signal. Based on these results, Labitzke found in 1987 that a signal of the 11-year Sunspot Cycle (SSC) emerged when the arctic stratospheric temperatures and geopotential heights were grouped into two categories determined by the direction of the equatorial wind in the stratosphere (QBO). This first study was based on 30 years of data (1957-1986), that is barely three solar cycles. ”
– http://strat-www.met.fu-berlin.de/labitzke/moreqbo/MZ-Labitzke-et-al-2006.pdf
links to ren’s last citation:
http://file.scirp.org/Html/3-5500060_21743.htm
http://www.scirp.org/journal/PaperDownload.aspx?paperID=21743
Great stuff all – thanks for your efforts.