NASA Mars Orbiters Reveal Three Types Of Regional Dust Storms Occur At The Same Times Each Year

The researchers discovered that there are large regional-scale dust storms take place during the dusty season on Mars or during the southern hemisphere spring and summer. These storms are identified as A, B, and C in seasonal order. The Martian year lasts about two Earth years.

The study was published in Geophysical Research Letters, a journal of the American Geophysical Union. It was led by David Kass of NASA's Jet Propulsion Laboratory, Pasadena, California and the instrument scientist for the Mars Climate Sounder on NASA's Mars Reconnaissance Orbiter and other scholars.

David Kass stated that when they look at the temperature structure instead of the visible dust, they finally see some regularity in the large dust storms. He further said that recognizing a pattern in the occurrence of regional dust storms is a step toward understanding the fundamental atmospheric properties controlling them. He added that this gives them a valuable opening.

In the study, the storms are identified as A, B, and C in seasonal order. This is to evaluate the zonal mean Pa daytime temperature retrievals from TES/MGS and MCS/MRO over 6 Mars Years. The dust field at 50 Pa implies that warming in the southern hemisphere is governed by direct heating. Meanwhile, the northern high latitude warming is a dynamical response. The researchers classified the A storms as the springtime planet-encircling southern hemisphere events. Meanwhile, the B storms are the southern polar events that begin near perihelion and finished in the solstice. C storms southern summertime events begin after the end of the B storm. The C storms suggest the most inter-annual variability.

The study is able to recognize the patterns and categories of dust storms. This is beneficial for planning robotic and human missions to the surface of the red planet. The researchers can also understand how seasonal local events affect global weather in a typical Mars year, as stated by the American Geophysical Union.

Mars orbiters have been operating since 1997, according to NASA. The Mars Climate Sounder on Mars Reconnaissance Orbiter has reached Mars in 2006. Meanwhile, the Thermal Emission Spectrometer on Mars Global Surveyor examined Mars from 1997 to 2006.