[Changes in Earth’s climate, from short term seasonal changes to 60-year and 1000-year cycles, greatly affect our need for and usage of energy – for heating and air conditioning. The Sun provides the Energy for Earth’s climate. There is a wealth of information available on changes in the Sun’s properties. Here are two such articles, one dealing with the current Sunspot cycle, and the other trying to find a correlation between Solar Wind Speed & Magnetic Polarity variation compared to the North Atlantic Sea Surface Temperature. – Bob]
Current Solar Cycle Now 3rd Weakest Ever Observed – Least Active Since Dalton Minimum 200 Years Ago!
The sun in April also was quiet in what has been so far a relatively calm solar cycle (SC). The sunspot number (SSN) was 38.0, which is 50% of what is typically normal for month no. 89 into a solar cycle. The impressive drop in activity is seen clearly in the following chart:
Figure 1: Sunspot activity since December 2008 for the current SC 24 is depicted by the red curve and is compared to the mean (blue). Over the past 4 months it has been very similar to SC 5 (black).
Also the divergence with respect to the sun’s polar field has increased. We reported on this in March. The south polar field is now close to 4 times stronger than the weaker northern field. Such a diverging development has never been observed at this stage into the cycle since observations began 40 years ago. We’ll continue monitoring this development and keep you informed!
Our monthly diagram which compares all the past observed cycles since 1755 now shows something special:
Figure 2: The accumulated sunspot anomalies from the mean for all cycles, 89 months into the respective cycle. The differences between each month for all cycles and the mean value (blue curve in Figure 1) is the source of the data.
Accounting for April 2016 (solar cycle month no. 89) it is clear that the current SC 24 is weaker in total than SC 7, which occurred from 1823 to 1833 during the so-called Dalton Minimum. Therefore our previous month’s suspicion that SC 7 would be surpassed has now been quickly confirmed as correct.
Currently SC 24 is now the weakest in close to 200 years, since SC 6.
The Solar Wind may be changing the surface temperature of the North Atlantic
Re-Blogged From JoNova
The solar wind blasts charged particles, electrons, stuff, towards Earth at 500 km a second — that’s one to two million miles per hour. It speeds up, slows down and shifts in direction as it travels past the Earth and has its own magnetic field. The wind speed varies from 300 km per second up to 800 and the impact on Earth changes with our magnetic field and our seasons. You might think this kind of monster flow might have some effect on our climate. But modern climate models are 95% certain that none of this matters. Only crazy people would think that a electrons flying past at a million miles per hour could “do something” to our stratosphere, or ozone, or cloud cover.
Curiously, a recent study shows that when the solar wind is fastest, the North Atlantic is coldest on the surface. The NAO (North Atlantic Oscillation) appears to correlate. The effect is strongest in the northern winter months. Notably the modern expert climate models fail to predict any of the cycles within our major ocean basins. How immature is our understanding of space weather?
Could changes in the solar wind be the driver of the NAO? Will it turn out to be the mechanism for Force N or D?
The solar-wind speeds peak about 3 or 4 years after the TSI and sunspots peak in each cycle. That doesn’t suggest the one solar cycle lag we are looking for. Perhaps if we had more data on solar wind speeds we could figure out whether the wind speeds correlated with the TSI in the cycle earlier?
Why the North Atlantic? Researchers don’t know exactly, they speculate:
The North Atlantic region seems to be favored for many of the observed responses, as found in the correlation of atmospheric
geopotential height (GPH) with solar wind geo-effective electric field (GEF) (Boberg and Lundstedt, 2003); of GPH with solar wind speed (SWS) (Zhou et al., 2014); and of surface air temperature (SAT) with energetic electron precipitation (EEP) and the geomagnetic activity that accompanies it (Seppälä et al., 2009; Baumgaertner et al., 2011; Maliniemi et al., 2013).
Every second solar cycle is different
When the sun flips north-south polarity the wind is more likely to hit Earth at a different angle – described as the solar wind clock angle. The Bz component is the north south component. Bz negative phases which are “southward” interplanetary magnetic conditions. That’s also when the geomagnetic storm activity is highest. So every second solar cycle the correlation changes.
Below the Fig 6a is Bz minus, and Fig 6 b is Bz positive.
Something is going on in the Bz negative cycles in the far northern Atlantic — (that’s the blue blob near Greenland in fig 6a).
In Fig. 6(a) we see a stronger SST response to the SWS when Bz is negative than in 6(b) when Bz is positive, in the high geomagnetic
latitude region near Iceland and southern Greenland.
With negative Bz more solar wind energy enters the magnetosphere–ionosphere system than with positive Bz, increasing energetic particle precipitation and ionospheric electric fields associated with magnetic storms. Increased response with negative Bz is not consistent with UV or total irradiance forcing.
If the correlation is meaningful, the next question is whether this is driven through stratospheric ozone, or though an electrical response of clouds and storm dynamics. It’s all speculation at this stage.
The Australian BOM Solar Wind Speed page
H/t Lance (Siliggy) and thanks to Lance W too.
A significant correlation between the solar wind speed (SWS) and sea surface temperature (SST) in the region of the North Atlantic Ocean has been found for the Northern Hemisphere winter from 1963 to 2010, based on 3-month seasonal averages. The correlation is dependent on Bz (the interplanetary magnetic field component parallel to the Earth’s magnetic dipole) as well as the SWS, and somewhat stronger in the stratospheric quasi-biennial oscillation (QBO) west phase than in the east phase. The correlations with the SWS are stronger than those with the F10.7 parameter representing solar UV inputs to the stratosphere. SST responds to changes in tropospheric dynamics via wind stress, and to changes in cloud cover affecting the radiative balance. Suggested mechanisms for the solar influence on SST include changes in atmospheric ionization and cloud microphysics affecting cloud cover, storm invigoration, and tropospheric dynamics. Such changes modify upward wave propagation to the stratosphere, affecting the dynamics of the polar vortex. Also, direct solar inputs, including energetic particles and solar UV, produce stratospheric dynamical changes. Downward propagation of stratospheric dynamical changes eventually further perturbs tropospheric dynamics and SST.