Press Release

Antarctic scientists keep eyes on upper atmosphere

By SpaceRef Editor
December 12, 2005
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Antarctic scientists keep eyes on upper atmosphere

By Steven Profaizer, Antarctic Sun staff

Breathe in. Blow a bubble. Watch a storm.

All this happens in the troposphere, the first 8 to 10 kilometers above sea level where our lives take place. It contains the air we breathe and the weather we see.

But our atmosphere extends above the clouds, above the jumbo jets, even above the ozone layer. The atmosphere extends about 800 kilometers above the planet’s surface. While most of this region is far out of reach, it is nonetheless an essential part of the Earth’s atmospheric structure and affects everything living hundreds of kilometers below on a daily basis.

A team of scientists at the South Pole, led by Gulamabas Sivjee of the Embry Riddle Aeronautical University, is studying the regions of the atmosphere called the mesosphere and thermosphere – specifically the area located between about 80 and 300 kilometers above the planet’s surface. That is the area that enables long-distance radio communication and allows us to walk outside without being bombarded with high-energy protons hurled out by the sun.

“A lot of people don’t realize how the atmosphere is connected together,” said Irfan Azeem, a member of the science team. “What happens at one level often affects the others.”

The group studies the upper atmosphere to better understand its physical nature and chemical structure. The project’s core goals lie in its examination of aurora-causing charged particles and of the atmosphere’s dynamics in the study area.

The sun spits out high-energy protons and electrons. From the ground, interactions of these charged particles with the upper atmosphere appear as the aurora borealis and aurora australis, or the Northern and Southern lights.

Part of the team’s mission is to match up the different types of particles with the auroras they create, Azeem said. Equipped with this information, engineers can improve current safety designs of space shuttles and satellites.

“This study allows us to better understand the environment spacecrafts fly in,” Azeem said. “If we can detect and identify these particles, we can better know what high-energy particles spacecrafts will face. We need to take this information into account when designing them.”

To conduct their studies, the scientists use a complex suite of four instruments to gather information about very faint emissions from atomic and molecular particles in the upper atmosphere. “The reason we have different instruments is that we are using them to look at different pieces of the information,” Azeem said. “We are basically tuning our instruments for different regions of the spectrum we are looking at.”

The group’s other main focus is the dynamics of this region of the atmosphere. Part of this research includes studying energy-carrying waves traveling through the atmosphere. “If you drop a stone in a pond, you get ripples. Similar tiny ripples appear in the atmosphere,” Azeem said. “The waves permeate from the lower atmosphere and transfer energy from one place to another.”

One of the mechanisms for creating such waves is air flowing over mountains. The energy and air flow formed as the air is pushed up over a mountain continues upward into the upper atmosphere, Azeem said.

By understanding the mechanics of these waves, the scientists hope to help others better guide the trajectory of satellites, rockets and space shuttles.

The program also helps to support NASA’s Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite.

TIMED is NASA’s satellite-based effort to study the same regions of the atmosphere that Azeem’s group studies from the South Pole. The scientists provide ground-based information to fill in any gaps in the satellite’s data.

NSF-funded research in this story: Gulamabas Sivjee, Embry Riddle Aeronautical University,

SpaceRef staff editor.