Related Experiment Video
Updated: Jul 12, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Interannual variability of global dust storms on Mars
Science (New York, N.Y.)
|October 24, 1986
Summary
Global dust storms on Mars depend on hemisphere circulation patterns. Northern hemisphere dust can weaken the southern Hadley circulation, preventing planet-encircling dust events.
Area of Science:
- Planetary Science
- Atmospheric Science
- Mars Science
Background:
- Global dust storms on Mars exhibit interannual variability, occurring in some years but not others.
- The Viking missions provided four Mars years of data, offering insights into these storm patterns.
Purpose of the Study:
- To infer distinguishing characteristics of Martian global dust storms based on available data.
- To investigate the role of atmospheric circulation, specifically the Hadley circulation, in the onset and variability of these storms.
Main Methods:
- Analysis of Viking mission data spanning four Mars years.
- Numerical simulations to model the impact of atmospheric conditions on dust storm development.
Main Results:
- Global dust storms are associated with dust raised in the southern hemisphere and spread by an intensified Hadley circulation.
- Years without global storms show dust raised in the northern hemisphere, but it does not spread globally.
- Northern hemisphere dust haze weakens the cross-equatorial Hadley circulation, reducing the likelihood of global dust storm development.
Conclusions:
- The interannual variability of Martian global dust storms may result from hemispheric circulation competition or dust cycling between hemispheres.
- The Hadley circulation plays a critical role in initiating global dust storms, with northern hemisphere dust acting as a potential inhibitor.
Related Concept Videos
01:50Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
01:16What is Climate?
Climate refers to the prevailing weather conditions in a specific area over an extended period. As the saying goes, “Climate is what you expect. Weather is what you get.” Climate is influenced by geographic factors, such as latitude, terrain, and proximity to bodies of water.
01:10Kepler's First Law of Planetary Motion
In the early 17th century, German astronomer and mathematician Johannes Kepler postulated three laws for the motion of planets in the solar system. He formulated his first two laws based on the observations of his forebears, Nikolaus Copernicus and Tycho Brahe.
Polish astronomer Nikolaus Copernicus put forth a theory that stated a heliocentric model for the solar system. According to this heliocentric theory, all the planets, including Earth, orbit the Sun in circular orbits.
On the other hand,...
Polish astronomer Nikolaus Copernicus put forth a theory that stated a heliocentric model for the solar system. According to this heliocentric theory, all the planets, including Earth, orbit the Sun in circular orbits.
On the other hand,...
01:24Acceleration due to Gravity on Other Planets
The gravitational acceleration of an object near the Earth's surface is called the acceleration due to gravity. It can be measured by conducting simple experiments on Earth. However, such an experiment is impossible to conduct on the surface of other planets.
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...
01:18Variation of Atmospheric Pressure
Change in atmospheric pressure with height is particularly interesting. The decrease in atmospheric pressure with increasing altitude is due to the decreasing gravitational force per unit area as we move away from the surface of the earth.
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...
01:15Torque Free Motion
The torque-free motion refers to the movement of a rigid body in space when no external torques are acting upon it. This type of motion can be observed in environments where there are no external forces or frictions, like in outer space. For example, a rotation of Mars in space is a torque-free motion. Mars is an axisymmetric object, meaning it has an axis of symmetry along which it rotates, designated as the z-axis. The rotating frame of reference is defined such that the center of mass of...