How the sun warms the Earth, Part 1
The importance of the Earth to sun distance and orientation.
Terigi Ciccone 12-21-2024
Abstract. Many of us climate scientists and engineers fall victim to what “we know.” Our disciplines and specialties shape our views and focus. However, climate change is a multidisciplinary field where a dozen or more scientific specialties are required to try to grasp the causes of climate and climate change. Sadly, all too often the more we specialize in our fields of comfort, perhaps, the further we get from the truth. In climate studies, we must accept the fact that dozens of natural forces and cycles dominate the Earth’s climate and climate change. Some act independently and others in complex interactions among and between these forces and cycles. The science of climate and climate change is highly complex and poorly understood. The sun and its orientation to the Earth is one of the major control knobs for the Earth’s ever-changing weather, climate, and climate change. The public poorly understands how the sun warms the Earth, and the UN IPCC alarmists mislead us, saying it’s all about humanmade CO2, and that science is settled.
Introduction. Here, we start the discussion with a few of the natural and significant drivers of climate change, provide an overview of overlooked ones, and challenge many popularly accepted ones. We start by analyzing the science of the everchanging relationship between the Earth and the Sun and explore intriguing possibilities and their possible roles and contributions.
The Milankovitch Cycles. The
Milankovitch cycles are long-term variations in Earth's orbit and rotation and orientation that influence climate patterns over thousands of years. Named after Serbian scientist Milutin Milanković, these cycles encompass three main components: eccentricity, axial tilt, and precession. Together, they affect the amount and distribution of solar radiation Earth receives from the sun, driving glacial-interglacial cycles and long-term climate changes. So, even while the power output of the sun may be nearly constant these cycles are a major cause of climate change. [i] Let’s take a more detailed look and see how these “orbital cycles” affect climate change on Earth individually and collectively. In a follow-up article we’ll discuss in detail variations within the sun’s cycles as we have an impactful one that
recently started, the Grand Solar Minimum, auguring a possible significant cooling period in a few years.
Orbital or Eccentricity, [ii] Earth's eccentric cycle describes the variation in our planet's orbit from nearly circular to more elliptical. This cycle occurs in two main periods: approximately 100,000 years and 413,000 years. As Earth's orbit changes shape, it affects the planet's distance from the Sun at different points in its annual journey. When the orbit is more elliptical, there's a greater difference in solar radiation received between perihelion (when the sun is closest to the Earth) and aphelion ( when farthest from the Sun). This change in solar energy reaches up to 6.8%. Although the total annual change in solar radiation due to eccentricity is relatively small (about 0.167%), its effects become significant over long timescales. These variations contribute to long-term climate patterns, influencing the intensity of seasons and glacial-interglacial cycles. Currently, Earth's eccentricity is decreasing, approaching its most circular phase. Perhaps most interesting is that the Earth is closest to the sun in January and farthest from the sun in June. This fact moderates the Earth's winter-summer temperature spread acting together with the Axial tilt as described below.
Obliquity or Axial Tilt. [iii] Earth's axial tilt, which is currently at 23.4 degrees, plays a crucial role in mitigating temperature extremes and shaping our planet's climate. This tilt varies between 22.1 and 24.5 degrees over a 41,000year cycle, influencing the distribution of solar radiation across the Earth's surface. The axial tilt is primarily responsible for our seasons. As seen in Figure-1, the Earth orbits the Sun, different hemispheres receive varying amounts of direct sunlight throughout the year. This alternation prevents any single region from experiencing extreme heat, as the Northern and Southern Hemispheres take turns facing the Sun more directly.
Additionally, the tilt affects polar ice formation. At the current 23.4-degree tilt, the poles receive only about 40% of the energy that reaches the equator. This disparity allows for the accumulation of ice at high latitudes, forming massive ice sheets that significantly impact the Earth's climate system. The axial tilt works in conjunction with other Milankovitch cycles to mitigate temperature extremes over long periods. When the tilt is at its minimum, seasons become milder, with warmer winters and cooler summers. This gradual change allows snow and ice to accumulate at high latitudes, increasing Earth's albedo and promoting further cooling. Conversely, larger tilt angles lead to more extreme seasons and can contribute to deglaciation periods.
The tilt of the Earth's rotation axis is part of what allows an appropriate climate for Earth to support life. By altering what portions of the Earth get the majority of incoming sunlight, no region on Earth is allowed to heat to extreme temperatures.[2] This can be seen in Figure-2; throughout Earth's orbit around the Sun the Northern and Southern Hemispheres alternate which side directly faces the Sun, preventing any region from extreme heating.
Procession. Earth's precession is a cyclic wobble in its rotational axis occurring over approximately 26,000 years. It plays a significant role in mitigating temperature extremes and shaping long-term climate patterns. This phenomenon, combined with other Milankovitch cycles, helps create conditions conducive to life on Earth. Precession affects the timing of seasons relative to Earth's orbit, altering the intensity of solar radiation received in different hemispheres. Currently, the Northern Hemisphere experiences milder seasons, with perihelion being closest to the Sun during winter and aphelion at the farthest point during summer.
This configuration reduces seasonal extremes in the north while intensifying them in the south. Over time, precession gradually shifts these patterns, alternating which hemisphere experiences more extreme seasons. This longterm oscillation helps prevent any single region from enduring prolonged periods of extreme climate conditions, allowing for a more balanced distribution of solar energy across the planet.
Precession interacts with other orbital parameters, particularly eccentricity, to influence climate patterns. During periods of higher eccentricity, precession's effects on seasonal contrasts become more pronounced, contributing to the complex interplay of factors that drive glacial-interglacial cycles. By moderating temperature extremes over long timescales, precession helps maintain habitable conditions across different regions of Earth, supporting the diversity and resilience of life on our planet.
The Sun's Barycenter Wobble.
The Sun's barycenter wobble is a complex motion caused by the gravitational influence of the planets in our solar system, particularly the gas giants like Jupiter. The barycenter, or center of mass, of the solar system can range from near the Sun's center to slightly outside its surface, depending on the positions of the planets in their orbits. This wobble causes the Sun to move in a complex trajectory around the solar system's center of mass. The effect is most pronounced due to Jupiter's influence, given its significant mass compared to other planets. Go to this link to see what this complex phenomenon is https://en.wikipedia.org/wiki/Barycenter_(astronomy).
As the planets orbit, their changing positions alter the location of the barycenter, causing the Sun's wobble. While the Sun's wobble is an interesting astronomical phenomenon, its direct impact on Earth's climate change is questionable. The Earth's orbit around the Sun remains relatively stable increasing the Earth’s distance from the Sun by about a maximum of 5 million miles. The Sun's wobble is most significant in the context of exoplanet detection, where similar stellar wobbles can be observed using the Doppler effect to identify potential planets orbiting distant stars.
Summary.
The Milankovitch cycles are a reminder of the importance that gravity plays in establishing our climate. The Milankovitch cycles are the collective effect of changes in the Earth's movements upon its climate, named after Serbian civil engineer and mathematician Milutin Milanković. The eccentricity, axial tilt, and precession of the Earth's orbit vary in several patterns, resulting in 100,000-year ice cycles of the Quaternary glaciation over the last few million years. The Earth's axis completes one full cycle of precession approximately every 26,000 years. At the same time, the elliptical orbit rotates, more slowly, leading to a 21,000-year cycle between the seasons and the orbit. In addition, the angle between Earth's rotational axis and the normal plane of its orbit moves from 22.1 degrees to 24.5 degrees and back again on a 41,000-year cycle. Currently, this angle is 23.44 degrees and is decreasing.
Bottom line, when alarmists tell you we must do all we can to decarburize to net zero, just smile, say thank you, and walk away.
Details and references.
i[] Milankovitch cycles - Wikipedia
ii[] https://www.space.com/milankovitch-cycles
iii[] https://energyeducation.ca/encyclopedia/Axial_tilt