Solar cycle 24 continues the slump

Stronger westerly winds around Antarctica are increasing eddy activity in the Southern Ocean and consequently may be driving more heat southward across the formidable Antarctic Circumpolar Current – the world’s largest current (see map below).
Winds over the Southern Ocean are strengthening due, at least in part, to human-induced change such as ozone depletion and greenhouse gas emissions. Scientists, examining satellite measurements of the ocean surface and using high-resolution computer models, have found that the Antarctic Circumpolar Current only shows a slight acceleration when these winds blow stronger, but that there is a large increase in ocean eddy activity. Eddies are the ocean equivalent of atmospheric weather systems, and in the Southern Ocean they play a key role in moving heat southward toward the Antarctic continent.

More blurbs on Solar EUV and UV and the effects on earth’s atmosphere.

Initial 3-D neutral polar wind
Abstract
The high-latitude polar-cap region is a highly dynamic region with many interesting phenomena associated with it, including the ion and neutral polar winds, plasma patches, polar holes, etc. To elucidate these phenomena and the neutrals produced via charge exchange associated with them, a new 3-D high-latitude hydrodynamic model of the polar-cap region has been developed. The model solves for H+, O+, Hs, Os, and electrons taking into account the effects of precipitating auroral electrons and convection electric fields. The first results of the model show a highly complex system at high-latitudes, with neutral stream particles flowing in all directions due to the combined effects of charge exchange and plasma convection.
http://www.sciencedirect.com/science/article/pii/S0273117705012184

January, 2013 SSRC HAS BEEN SELECTED BY NASA TO DEVELOP NEXT GENERATION EXTREME-ULTRAVIOLET (EUV) SOLAR RADIOMETERS FOR SPACE WEATHER AND SOLAR PHYSICS APPLICATIONS.
A fundamental requirement for understanding and predicting solar variability and the effects of solar radiation on space weather and Earth climate is the accurate measurement of the radiation emitted by the Sun. While the Sun is brightest in the visible, the fainter and highly variable EUV radiation plays a dominant role in heating the thermosphere, altering the neutral density and electron density, creating the ionosphere…
http://www.spacesystemsresearch.com/SSRC-MediaJan2013.html

Recent developments in ionosphere–thermosphere modeling with an emphasis on solar-variability
Abstract
The Utah State University modeling developments have led to new results in several areas of ionospheric research. This review will present the most recent of these results and their synergisms with both ground-based and satellite-based observations. Particular attention is given to new results associated with solar variability, a central theme to the TIGER program. The effect on the ionosphere of differences in solar X-EUV spectra will be demonstrated by studies using the time-dependent ionospheric model, while their effect on the coupled thermosphere–ionosphere system will be shown using a new model, the global average ionosphere thermosphere model. How the dayside solar-produced plasma contributes to sub auroral polarization streams, storm enhanced densities, tongues of ionization, plasma patches, polar wind jets, and polar cap scintillations, will be described via recent modeling results from a variety of coupled or driven thermosphere, ionosphere, and magnetosphere models. The review will indicate the need for improved solar output specification, whether via observations or models. These improvements need to be over the flare through solar cycle time scale, with particular attention to the short wavelength end of the spectrum.
http://www.sciencedirect.com/science/article/pii/S0273117705012196

INVESTIGATION OVERVIEW
The Solar EUV Experiment (SEE) investigation contributes primarily to the NASA TIMED mission goal to characterize the sources of energy responsible for the thermal structure of the mesosphere, the lower thermosphere, and the ionosphere (MLTI). These energy sources include solar radiation, solar energetic particles, Joule heating, conduction, dynamical forcing, and chemical energy release. Of these energy inputs, the solar vacuum ultraviolet (VUV) radiation below 200 nm is the dominant global energy source for heating of the thermosphere, creating the ionosphere, and driving the diurnal cycles of wind and chemistry. The estimated amount of heating by solar VUV radiation as a function of altitude in Earth’s atmosphere is shown in Figure 1 for solar minimum and solar maximum conditions. Changes in the amount of solar VUV radiation result in corresponding changes in the energy balance of the upper atmosphere, dynamics, and photochemistry. While solar cycle variability near 200 nm is only about 10%, the solar cycle variability at shorter wavelengths is typically a factor of 2 to 3 for chromospheric emissions and a factor of 10 to 100 for coronal emissions. The variability of both of these emissions are not well understood, especially at the shortest wavelengths below 40 nm. A detailed quantitative understanding of the changes in the solar VUV irradiance and the basic state variables, temperature and densities of N 2 , O 2 and O, are essential to detailed investigations of atmospheric energetics, dynamics, and chemistry….
The Sun varies on all time scales and the amount of variability is a strong function of wavelength. Our present understanding is that in the visible portion of the spectrum, the intrinsic solar cycle variability is on the order of one-tenth of a percent. Moving into the middle ultraviolet (200 to 300 nm), the amount of radiation decreases rapidly while the variability increases by an order of magnitude and reaches one to a few percent. Further into the FUV and EUV, the amount of radiation decreases further while the solar cycle variability continues to increase with the magnitude of the variation approaching a factor of two, for example at the H I Lyman-α emission at 121.6 nm, and finally to an order of magnitude variations in the extremely high temperature coronal lines. Solar radiation below 200 nm consists of emission lines superimposed on the rapidly declining continuum. These emission lines arise in higher temperature layers of the outer solar atmosphere under non-LTE conditions and are strongly related to the magnetic activity of the Sun as seen, for example, in plage regions. It is known that these emission lines exhibit large amplitude variability during an 11 year solar cycle while the underlying FUV continuum portion is far less variable11. The XUV region is dominated completely by emission lines, primarily coronal lines which may vary by orders of magnitude during an 11 year solar cycle. Short term variations, lasting from minutes to hours, are related to eruptive phenomena on the Sun; intermediate term variations, modulated by the 27-day rotation period of the Sun, are related to the appearance and disappearance of active regions on the solar disk, and the more elusive long term variability is related to the 22-year magnetic field cycle of the Sun. The long term variation is poorly determined due to the lack of measurements and to the inadequate long term accuracy of previous satellite solar instruments…..
lasp.colorado.edu/see/documents/SEE_Instr_Paper.pdf‎

….Relative long-term variations of the UV irradiance (120–290 nm) are well
described by the Mg II index…