Mapping the atmosphere’s global circulation

TES found that when the Sun stands over the Martian equator, the atmosphere develops a pattern with one northern hemisphere circulation cell and a similar southern one. At the solstices later in the year, however, the pattern shifts to a single larger cell in the warmer hemisphere that spreads across the equator. Also at the solstices, the large circulation cell spawns an eastward-flowing jet stream moving at more than 550 kilometers (340 miles) per hour.

TES mapped the atmosphere’s global circulation for three Mars years and found that when the Sun stands over the Martian equator, the atmosphere develops a pattern with one northern hemisphere circulation cell and a similar southern one. At the solstices later in the year, however, the pattern shifts to a single larger cell in the warmer hemisphere that spreads across the equator. Also at the solstices, the large circulation cell spawns an eastward-flowing jet stream moving at more than 550 kilometers (340 miles) per hour.

Using TES data, a cross-section of Mars’ atmosphere from the south pole (left) to the north pole (right) shows in the upper panel the warm atmosphere (red colors) in the south as southern summer begins. (It’s still pretty chilly: 240 kelvins is -27 degrees Fahrenheit.) The lower panel shows a high-speed jet (red colors) has developed in the north at the same time. It has winds greater than 160 meters per second (365 miles per hour).