The Moon’s Tidal Push
Towards a New Theory of Climate Resilience
The Moon has a strong gravitational affect on the oceans, including through a force I am calling the Moon’s Tidal Push, specifically a subsurface wave that I hypothesis varies in amplitude and frequency driven primarily by changes in the Moon’s declination cycle.
The Moon’s Tidal Push is stronger when the Moon swings furthest north and south to an 18.6-year beat, moving at greater speed above the equator like a swing speeding through its lowest point. This push affects a slow wave across the Pacific Ocean at depth, flipping between cold and warm every few years, which changes the Southern Oscillation Index (SOI). These changes will affect weather globally, creating condition that will likely exacerbate localised flooding or droughts.
That the SOI exists and affects weather patterns is not a new discovery, this pulse can be measured indirectly as a change in atmospheric pressure between Darwin and Tahiti with daily and monthly values back to the 1870s. My contribution is to explicitly acknowledge the physical mechanism underlying the two phases and show that by taking more direct measures of the phenomenon, specifically the varying amplitude and frequency of the wave, we can better anticipate the cycle.
El Niño: A warming phase where sea surface temperatures (SSTs) in the central and eastern Pacific are significantly higher than average. This is known to create particular weather patterns, increasing the likelihood of rainfall in some regions and droughts in others.
La Niña: A cooling phase where SSTs in the central and eastern Pacific are lower than average. This often results in opposite weather effects compared to El Niño, such as reduced rainfall in typically wet areas.
Until now, it has been considered difficult to make accurate forecasts when conditions are considered neutral. This is because surface anomalies are weak, but the cycle continues and can be measured in other ways.
The Mechanism
I hypothesis the 18.6-year lunar nodal cycle that directly impacts the Moon’s declination cycle will affect the strength of tidal forcing, influencing the wave’s energy, potentially affecting its propagation characteristics.
Better Weather Forecasts
It is not fashionable to acknowledge external drivers of global weather and climate, but necessary if we are to more reliably predict the weather.
Given the predictable cyclical nature of this key driver, already used to accurately predict local sea tide heights and times that vary with geographic location, the incorporation of the Moon’s Tidal Push into my new Theory of Climate Resilience provides a framework for better rainfall forecasts.
The following variables could be explicitly feed into artificial neural networks to generate daily, monthly and seasonal rainfall forecasts:
1. Subsurface Ocean Temperature
Specifically, temperature anomalies along the thermocline (e.g., the 23.5°C depth line) from the western Pacific to the eastern Pacific. These anomalies are critical for identifying the eastward-propagating subsurface ocean wave that drives the ENSO lifecycle.
2. Sea Surface Temperature (SST)
SST anomalies in key regions like Nino3.4 (central-eastern Pacific) are essential for tracking the development of El Niño or La Niña phases.
3. Vertical Velocity
Measurements of upwelling rates in the eastern Pacific, which indicate how subsurface temperature anomalies are advected to the surface.
4. Sea Level Pressure (SLP)
SLP anomalies, which are closely tied to atmospheric circulation changes during ENSO events.
5. Surface Winds
Westerly or easterly wind anomalies, which influence ocean-atmosphere coupling and feedback mechanisms.
6. Sea Surface Height (SSH)
Variations in SSH, which can indicate changes in ocean heat content and subsurface wave activity.
7. Lunar Tidal Gravitational Force:
Measurements of lunar tidal forces, as they are hypothesised to drive the subsurface ocean wave associated with ENSO.
8. Ocean Salinity
Salinity profiles, which can affect density and thermocline dynamics.
The most skilful rainfall forecasts will also include historically accurate rainfall and temperature data series that extend back at least 100 years, because local conditions will always modify the influence and impact of the Moon’s Tidal Push.
Acknowledgements
My thinking about this mechanism, which I am calling The Moon’s Tidal Push and that is the third plank of my new Theory of Climate Resilience, has been greatly influenced by my previous forecasting efforts with John Abbot; that research was funded by the B.Macfie Family Foundation. Long before that, my late father John Turnour was explaining the declination cycle to me; he always knew where the Moon was in the sky and at what point in its declination cycle. He was a farmer, who cared about his cattle.
I've received some requests that I provide more background information, even how the Moon causes two sea tides in each day.
1.Why Two High Tides?
The Moon’s gravity pulls the ocean toward it, creating a bulge of water on the side of Earth facing the Moon. At the same time, on the opposite side, water "lags" due to inertia (Earth is pulled toward the Moon more than the water on the far side), forming a second bulge. As Earth rotates daily, any point on its surface passes through both bulges, giving you two high tides about 12 hours apart. This is why we see two highs even though the Moon only orbits once.
2. How the Sun Complicates Things
The Sun also exerts gravitational pull on Earth’s oceans, but it’s weaker than the Moon’s because the Sun is much farther away (its tidal force is about 46% of the Moon’s). The Sun’s effect combines with the Moon’s, leading to variations in tide strength:
Spring Tides: When the Sun, Moon, and Earth align (during full or new moons), their gravitational pulls reinforce each other, causing higher high tides and lower low tides. These occur roughly every 14–15 days.
3. Neap Tides: When the Sun and Moon are at right angles (first or third quarter moons), their pulls partially cancel out, leading to smaller tidal ranges (less extreme highs and lows). These also happen about every 14–15 days. The Sun’s influence modulates the tides’ amplitude but doesn’t change the twice-daily pattern driven by the Moon and Earth’s rotation.
4. The Lunar Declination Cycle
The Moon’s orbit isn’t perfectly aligned with Earth’s equator—it’s tilted, and its position relative to the equator (called declination) shifts over a 27.3-day cycle. This affects tides because the Moon’s gravitational pull varies in strength depending on whether it’s overhead at the equator, north, or south of it:
When the Moon is near the equator (declination near 0°), the two daily high tides at a given location tend to be similar in height because the tidal bulges are symmetrically aligned with Earth’s rotation.
When the Moon is at maximum declination (up to ±28.5° north or south), one tidal bulge is stronger in the hemisphere where the Moon is overhead, leading to diurnal inequality—the two daily high tides can differ significantly in height, especially at higher latitudes. For example, one high tide might be much higher than the other in places like the Gulf of Mexico.
This cycle repeats every 27.3 days, causing subtle shifts in tidal patterns that are more noticeable in certain coastal areas.
Putting It Together
The two high tides per day come from Earth passing through the Moon’s two tidal bulges as it rotates. The Sun amplifies or dampens these tides based on its alignment with the Moon, creating spring and neap tides. Meanwhile, the Moon’s declination cycle tweaks the relative heights of the two daily tides as its position shifts north or south. Local geography, like bays or channels, can further shape how these forces play out at the specific location of interest.
It is complicated and fascinating, and important stuff if we are to understand natural cycles, including weather and climate cycles. It all begins here.
Yet another CO2 free contributor to climate change.