A new model suggests volcanic activity in Mars’ distant past spewed enough greenhouse gases to melt ice and warm the atmosphere
Why does the cold, barren surface of Mars contain geological features that appear to have been formed by flowing water: river valleys, lake basins, and deltas? A new model, published online in Nature Geoscience, suggests that sulfur spewed into the Martian atmosphere by ancient volcanoes could have periodically warmed the surface enough for the ice to melt and water to flow.
Weizmann Institute of Science
Satellite image of Olympus Mons on Mars, the largest volcano in the solar system at about three times the height of Mount Everest. Around 3.5 to 4 billion years ago, the release of volcanic gases, especially the greenhouse gas sulfur dioxide, may have warmed the surface of Mars episodically, melting the ice and thereby explaining the presence of geomorphological features indicative of the flow of water on the planet’s ancient surface.
Indeed, the signs of flowing water have been a puzzle, as the latest generation of climate models portrays Mars as an eternally ice-cold planet with all of its water frozen solid, especially early in its history, when the Sun was weaker than it is today.
Today, most of that water is locked in polar caps. Dr. Itay Halevy of the Weizmann Institute of Science’s Department of Earth and Planetary Sciences and Dr. James Head III of Brown University thought the answer might lie in the now dormant volcanoes on the planet’s surface, which could have played a larger role than previously thought in shaping its climate.
On Earth, volcanic emissions – sulfur compounds and ash – tend to cool the climate. But in the presumably dusty early atmosphere of Mars, the net effects might have been different. To understand their impact, Drs. Halevy and Head first calculated the size of ancient volcanic eruptions, based on the volcanic rock formations observed on the planetary surface today.
Their estimations show that the eruptions were violent – hundreds of times the force of the average eruption on Earth – and may have lasted up to a decade. This means that the amounts of gases spewed from the mouths of these volcanoes, from what we know of Earth’s eruptions, must have been enormous.
The team’s simulations showed large amounts of the greenhouse gas sulfur dioxide mixing into the atmosphere. But warming caused by the sulfur dioxide was thought to be outweighed by cooling due to the creation of sun-blocking sulfuric acid particles, which form as sulfur dioxide reacts in the atmosphere.
Drs. Halevy and Head showed that, in an atmosphere already as dusty as that of Mars, the sulfuric acid mostly forms thin coatings around particles of mineral dust and volcanic ash, subduing the added cooling. The net effect, according to the model the scientists created, was modest warming – just enough to allow water to flow at low latitudes on either side of the planet’s equator.
Liquid water may have flowed in these regions for tens to hundreds of years during and immediately after volcanic eruptions. The model suggests that during these brief, but intense, wet periods, the surface of the planet could have been carved by flowing rivers and streams.
Dr. Itay Halevy’s research is supported by the Sir Charles Clore Research Prize; the Carolito Stiftung; the estate of Olga Klein Astrachan; and the European Research Council.
The Weizmann Institute of Science in Rehovot, Israel, is one of the world’s top-ranking multidisciplinary research institutions. The Institute’s 3,800-strong scientific community engages in research addressing crucial problems in medicine and health, energy, technology, agriculture, and the environment. Outstanding young scientists from around the world pursue advanced degrees at the Weizmann Institute’s Feinberg Graduate School. The discoveries and theories of Weizmann Institute scientists have had a major impact on the wider scientific community, as well as on the quality of life of millions of people worldwide.
Director, Science Content
Jennifer Manning | newswise
Looking for freshwater in all the snowy places
26.06.2019 | NASA/Goddard Space Flight Center
Earthquake impact on submarine slopes: subtle erosion versus significant strengthening
26.06.2019 | Universität Innsbruck
From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.
Reducing machine downtime, manufacturing defects, and excessive scrap
The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.
Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...
The well-known representation of chemical elements is just one example of how objects can be arranged and classified
The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...
Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.
Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...
Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.
The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...
24.06.2019 | Event News
29.04.2019 | Event News
17.04.2019 | Event News
26.06.2019 | Materials Sciences
26.06.2019 | Physics and Astronomy
26.06.2019 | Health and Medicine