How Does the Moon Impact Weather?

From the inability to fall asleep at night to a surge in emergency room visits, the moon is said to impact everything. But what about the weather?

Concrete research on the moon’s impact on the weather is not as developed as you may think. However, one thing is for certain: the moon’s gravitational pull affects ocean tides.

The Moon and Ocean Tides

Any given portion of Earth that is closest to the moon is strongly influenced by gravity. When the moon is over the ocean, the water is pulled toward it, creating a tidal bulge.

There are two low tides and two high tides that occur in every 24 hour period. During a new moon or a full moon, high tides are significantly higher, and low tides are lower than normal. Additionally, low tides are more moderate than usual during the first and last quarter moon.

Tides impact the movement of currents, which directly impact the weather through the amount of warming or cooling water moving through a given area. Think of weather events like El Niño, which is a climate cycle in the Pacific Ocean beginning when warm water in the western tropical Pacific Ocean shifts eastward along the equator toward South America’s coast. Water temperatures combined with wind strength and direction shape weather events like El Niño.

The Moon and Polar Temperatures

Surprisingly, the moon also affects polar temperatures. Satellite measurements of the atmosphere’s temperature show that the poles are 0.56 degrees Celsius (0.99 degrees Fahrenheit) warmer during a full moon than a new moon. Although slight, these temperature changes often impact the weather around the world.

The Moon and Rainfall

Finally, the moon’s tidal forces affect the amount of rainfall on Earth. Research by the University of Washington shows that the lunar forces impact the amount of rain on Earth. Researchers say that when the moon is high in the sky, it creates bulges in the planet’s atmosphere, leading to imperceptible changes in the amount of rain that falls below. These bulges create pressure on the side of the planet the moon is directly above.

Higher pressure increases the temperature of air parcels. Warmer air holds more moisture, creating more rainfall. Increases in air pressure from the moon also increase relative humidity, which is more favorable for precipitation.

The moon, although hundreds and thousands of miles away, impacts our lives here on Earth. Next time it feels a little more humid than normal or you hear about El Niño in the news, look up at the sky and think about the moon.