The Sun At Rest

The Sun is a constant force that keeps the planets in orbit. Its light illuminates us day after day, but its intensity is not continual and can increase or decrease over the years.

Image 1: The sun presents zones of different intensities of radiation.Image by NASA.

Our Earth and the Sun go through phases and changes. Over time, science has managed to identify and describe these facts more clearly. The intensity of the Sun varies and can increase or decrease indiscriminately.

Currently, it is going through a less active phase, called solar minimum. The Sun experiences regular 11-year intervals that include energetic peaks of activity, followed by lows. During the maximum point, the Sun shows more sunspots and solar flares.

Sunspots are areas of intense magnetic activity on the Sun surface, a firestorm; that appears as an area of ​​darkness. Sunspots indicate solar activity, the birth of solar flares, and coronal mass ejections. Sunspots are immense and correspondent to the magnitude of our Sun.

Image 2: The solar points in the right image indicate high energy intensity.Image by NASA.

At a solar minimum, the Sun exhibits lower activity, which means fewer sunspots and less energy. In 2014, sunspots were at the maximum point, still were weak. However, the sunspots have declined since then, according to NASA.

"During solar minimum, the sun's magnetic field weakens and provides less protection against these cosmic rays," said Dean Pesnell, project scientist of the Solar Dynamics Observatory at NASA's Goddard Space Flight Center.

The most energetic particles, galactic cosmic rays, are created by explosions in our galaxy and can reach Earth, specifically, its upper atmosphere during a solar minimum.

Sunspots have been counted continuously every day since 1838, allowing scientists to establish the solar cycle and describe a repeating pattern in the increasing and decreasing activity on the Sun surface.

Image 3: The dangerous cosmic microwave rays would increase their entry to the earth.Image by Petra Rettberg / Researchgate.

Some solar scientists think that we could enter a "Great Solar Minimum" in the next few decades. The last time this happened was between 1650 and 1715 during what is known as the Little Ice Age in Earth's northern hemisphere.

"When the combination of volcanic aerosol cooling and low solar activity produced lower surface temperatures," according to NASA's Global Climate Change blog. "Even if a Great Solar Minimum lasted a century, global temperatures would continue to warm because more factors than just variations in sunrise change global temperatures on Earth, the most dominant of the current ones is warming from production. Human. Greenhouse Gas Emissions ".

Sunspots were absent by about 71 percent in 2020 through Sept. 21, 2020, compared with 77 percent in 2019, according to the U.S. National Oceanic and Atmospheric Administration's Center for Space Environment ( NOAA). In May this year, it hit 78 percent, sparking fears of a Little Ice Age.

Image 4: Explanations for the Little Ice Age include explosive volcanism and solar irradiance.

But they assure that this solar minimum will not cause another ice age because the state of our Sun does not influence the current increase in global temperature.

Magnetic fields on the visible surface and gigantic plasma currents are the two phenomena responsible for these fluctuations that emanate from within the star.

These fluctuations sometimes are superimposition by signals from exoplanets passing as an eclipse. Some cycles are only a few minutes, but some can last for months and even decades. Although, the intensity of the Sun is recently low. But it does not mean that there will be no global warming.

"There is another reason for the cooling, directly related to the Sun's magnetic field, which protects the Earth from harmful cosmic and galactic rays. In the absence of shielding, more rays reach the Earth and form clouds high in the atmosphere; it's causing the cooling, "according to Zarkhova of Northumbria University.

Image 5: The sun's magnetic field changes over time, reverse every eleven years.Image by NASA.

Zarkhova suggests that the planet's temperature could drop 1 ° C during the current vast solar minimum due to its longitude. The possible drop in temperatures has led people, including some scientists, to predict that minimal solar cooling could cause a Little Ice Age and offset rising temperatures due to global warming.

2020 is the second year in a row for a record number of sunspot absences. The most infamous occurred between 1645 and 1715 when a "Maunder Minimum" saw a prolonged minimum of sunspots; the sunspots were surprisingly rare for an extended period. 

The attenuation lowered temperatures in the northern hemisphere, especially in Europe, by between 1 and 1.5 degrees Celsius and resulted in icy rivers, long winters, and cold summers. Due to the complex impacts of declining solar activity on the abundance of ozone in the Earth's atmosphere and climate cycles such as the North Atlantic Oscillation (NAO).

The current solar minimum is at a record low peak in 9,000 years. The scientists think that the Sun may have been in a magnetic pause throughout that period. The last solar maximum was in 2013/2014, but it was among the weakest record.

Image 6: Northern lights in Iceland during solar maximum.Image by NASA. 

The state of the Sun has the most evident effect on the intensity and frequency of auroras. The more charged the solar wind has a direction towards Earth, the brighter and more frequent the northern and southern lights are. Either way, historically, a solar maximum is when auroras are most frequent and spectacular.

However, powerful auroras also appear during a solar minimum; due to the opening of "coronal holes" and the favorable direction of the solar wind.

Although it is a strange occurrence in the history course, its scope can be unpredictable. However, everything indicates that the planet's temperatures will increase due to environmental pollution even if the Sun is at its lowest intensity.

References

• Max Planck Institute. Variable sunshine. Aug 21, 2017. Link https://www.mps.mpg.de/Variable-sunshine.

• Ashley Strickland. CNN. The sun is experiencing a less active phase called 'solar minimum,' but it won't cause an ice age. May 20, 2020. Link https://edition.cnn.com/2020/05/19/world/solar-minimum-scn-trnd/index.html.

• Down To Earth. Akshit Sangomla. Cold comfort: The sun is cooling; doesn't mean there'll be no global warming. Wednesday 23 September 2020. Link https://www.downtoearth.org.in/news/science-technology/cold-comfort-the-sun-is-cooling-doesn-t-mean-there-ll-be-no-global-warming-73488.

• NASA. Lina Tran.  What Will Solar Cycle 25 Look Like?. Sep 17, 2020, Link https://www.nasa.gov/feature/goddard/2020/what-will-solar-cycle-25-look-like-sun-prediction-model.

• Forbes. Jamie Carter. The Sun Is Asleep. Deep ‘Solar Minimum’ Feared As 2020 Sees Record-Setting 100-Day Slump. May 12, 2020,10:00pm EDT. Link https://www.forbes.com/sites/jamiecartereurope/2020/05/12/the-sun-is-asleep-deep-solar-minimum-feared-as-2020-sees-record-setting-100-day-slump/?sh=6b4f62b85e28.

• NASA. FAQ: How Does the Solar Cycle Affect Earth's Climate?. Link https://www.nasa.gov/mission_pages/sunearth/solar-events-news/Does-the-Solar-Cycle-Affect-Earths-Climate.html.