Gravity Wave Activity in the Stratosphere and Mesosphere at the South Pole (2024)

FAQs

What are gravity waves in the mesosphere? ›

In the Earth's atmosphere, gravity waves are a mechanism that produce the transfer of momentum from the troposphere to the stratosphere and mesosphere. Gravity waves are generated in the troposphere by frontal systems or by airflow over mountains.

In a gravity wave, the parcel of air will try to remain at a location in the atmosphere where there are no forces causing it to rise or sink. Once a force moves the parcel from its natural state of equilibrium, the parcel will try to regain its equilibrium.

"There is also wind shear in a gravity wave, and the storm can take that wind shear and tilt it and make even more spin. All of these factors may increase storm rotation, making it more powerful and more likely to produce a tornado."

They form when air is forced upward by hills or mountains into a layer of stable air in the atmosphere. Gravity causes the air to fall back down, and it begins to oscillate, creating a ripple effect. Wind flowing over the Rocky Mountains, for example, can create gravity waves that are felt as turbulence on an airplane.

In the middle stratosphere (30–40 km), there is higher gravity wave activity near the equator in autumn in the middle stratosphere than in other seasons in 2020, and much less in 2021. The gravity wave activity is low (maximum 5 J kg⁻¹) compared to the lower stratosphere (maximum 10 J kg⁻¹).

“Gravitational waves are ripples in spacetime. When objects move, the curvature of spacetime changes and these changes move outwards (like ripples on a pond) as gravitational waves. A gravitational wave is a stretch and squash of space and so can be found by measuring the change in length between two objects.”

As a gravitational wave passes an observer, that observer will find spacetime distorted by the effects of strain. Distances between objects increase and decrease rhythmically as the wave passes, at a frequency equal to that of the wave.

We know, low tides and high tides occur due to the combined effects of the gravitational forces exerted by the moon and the sun on earth. Similarly, earthquakes are caused by the combined effects of the gravitational forces of the sun, the moon, and the other planets on Earth.

As gravity hugs the blanket of air to the Earth's surface, what physicists call a density gradient is set up in the air. The air near the ground is pulled on by gravity and compressed by the air higher in the sky. This causes the air near the ground to be denser and at a greater pressure than air at higher elevations.

Since its first historic detection, LIGO has discovered dozens more gravitational waves generated by merging black holes, a few colliding neutron stars and neutron star/black hole mergers, and even some 'mystery' events, where one of the objects was a black hole and the other was of unknown type (either an extra-heavy ...

Why are gravity waves important? ›

For example, gravitational waves created at the very birth of the universe travel unscathed through all the hot matter of the early universe, as the universe expanded. They didn't scatter. They didn't get absorbed. They bring the information from the birth of the universe to us today.

Nacreous clouds are some of the rarest clouds on the planet. They are a form of polar stratospheric cloud, which is a main culprit in chemical destruction of the ozone layer.

The main most important features in this region are strong zonal (East-West) winds, atmospheric tides, internal atmospheric gravity waves (commonly called "gravity waves"), and planetary waves.

Some material from meteors lingers in the mesosphere, causing this layer to have a relatively high concentration of iron and other metal atoms. Very strange, high-altitude clouds called "noctilucent clouds" or "polar mesospheric clouds" sometimes form in the mesosphere near the poles.

Compact binary inspiral gravitational waves are produced by orbiting pairs of massive and dense ("compact") objects like black holes and neutron stars. There are three subclasses of "compact binary" systems in this category: Binary Neutron Star (BNS) - two neutron stars orbiting each other.

Internal gravity waves are waves occurring in the interior of a stratified fluid, with buoyancy providing the restoring force which opposes vertical displacements. Such waves are ubiquitous in the atmosphere and ocean and are the internal counterpart to the familiar surface gravity waves.