Learn about the role dust plays in Earth’s climate, why scientists are interested in studying dust from space, and how to engage students in science with JPL’s STEM resources.
NASA’s instruments launched to the International Space Station in early summer will explore how dust affects global temperatures, cloud formation and the health of our oceans. The Earth Surface Mineral Dust Source Investigation, or EMIT, will be the first instrument of its kind, collecting measurements from space from some of the driest regions on Earth to understand the composition of dust-producing soils and the larger role of dust in climate change.
Read on to learn how the instrument works and why scientists hope to learn more about the composition of dust. Then explore how to bring science into your classroom with related climate lessons that bridge physics with engineering practice.
Why Is This Important?
Scientists have long studied the movement of dust. The fact that dust storms can carry tiny particles over great distances was reported in the scientific literature nearly two centuries ago by Charles Darwin as he sailed across the Atlantic on the HMS Beagle. What remains a mystery for years to come is what dust is made of, how it moves, and how it affects the health of our planet.
For example, we now know that dust deposited in snow accelerates snowmelt even more than an increase in air temperature. This means that dust dispersed in colder places can lead to increased snowmelt.
Dust can also affect the air temperature. For example, dust with more iron absorbs light and can cause the air to warm, whereas dust with less iron reflects light and is responsible for local cooling. The iron in the dust can also act as fertilizer for plankton in the oceans, supplying them with the nutrients they need for growth and reproduction.
Floating dust has the potential to change the composition of clouds and how quickly or slowly they form, which in turn can affect weather patterns, including the formation of hurricanes. That’s because clouds need particles to act as seeds on which droplets of water vapor in the atmosphere can form. This process of combining water particles, called nucleation, is one factor in how clouds form.
Thanks to EMIT, we will take the first step in understanding how the movement of dust particles contributes to local and global climate change by producing “mineral maps”. These mineral maps will reveal differences in the chemical makeup of dust, providing important information to help us model how dust can change Earth’s climate.
Learn more about what EMIT will do from JPL News
How it works
NASA has been exploring how dust moves around the world by combining field studies with cutting-edge technology.
Olga Kalashnikova, an aerosol scientist at NASA’s Jet Propulsion Laboratory and a co-investigator for EMIT, has been using satellite data to study atmospheric mineral dust for years, including tracking dust movement and investigating dust storm frequency trends. .
As explained by Dr. Kalashnikova, “From the ground, we can see what kind of dust is being lifted into the atmosphere by dust storms on a local scale, but with EMIT, we can understand the difference and where it comes from.”
EMIT is the first instrument designed to observe a significant part of the mineral dust cycle from space, allowing scientists to track different dust compositions on a global scale, not just one region at a time. To understand the impact of dust on Earth’s climate, scientists will use EMIT to answer key questions, including:
- How does dust lifted in the atmosphere change global temperatures?
- What role did dust play in nourishing our oceans when they were deposited?
- How dust particles in the atmosphere affect cloud nucleation; the process by which a cloud is ‘seeded up’ and begins to coalesce into a larger cloud?
To achieve its goal, EMIT will spend 12 months collecting so-called “hyperspectral images” of some of the driest regions on our planet that scientists and engineers have selected as areas of high dust mobility, such as North Africa, the Middle East, and southwest America. .
These images are measurements of light reflected from Earth below, calibrated to a different pattern, or spectrum of light that we see when certain minerals are present. The EMIT team has identified the 10 most common minerals, including gypsum, hematite, and kaolinite.
Why is this mineral important? One of the main reasons is the presence or absence of the element iron, found in some minerals but not in others.
Dr. Bethany Ehlmann is a planetary scientist and co-investigator for the EMIT project at Caltech and explains that when it comes to warming, “a little iron can help.” The iron in the mineral absorbs visible and infrared light, which means even a small amount of it will produce much warmer dust particles. The large amounts of warm dust in our atmosphere may have an impact on global temperatures because the dust particles radiate heat as they move, sometimes across the oceans!
Collecting images from outer space, of course, is no easy task, especially when trying to just look down. Yet it allows scientists to get a global picture that is impossible to capture from the ground. Field studies allow us to take individual samples from small places of interest, but from space, we can scan entire planets in remote places where no scientist can visit.
Of course, there are some complications in trying to study light reflected from the Earth’s surface, such as interference from clouds. To prevent this problem, the EMIT team plans to collect data at each location several times to ensure that the image is not obscured by clouds between the instrument and the mineral we are looking for.
The data collected by EMIT will provide maps of the dust composition of arid desert environments around the world, but the teams involved won’t stop there. Knowing more about what dust is made of opens the stage for a broader understanding of some of the complex processes that shape our global climate cycles. Upon completion of this study, EMIT’s mineral maps will support further campaigns to complete our global dust picture. For example, NASA hopes to combine data from EMIT with targeted field campaigns, in which scientists can collect windblown dust from the ground to learn more about where dust particles move over time and answer questions about what types of dust are present. The trip. .
In addition, missions such as the Multiangle Imager for Aerosols, or MAIA, will allow us to better understand the effects of these dust particles on air quality and public health.
Studying the Earth’s climate is a complex puzzle, consisting of many traceable features. These can range from the surface of the ocean to the particles in our atmosphere, but each contributes to measuring the health of our planet. Bring EMIT and NASA Earth Science into your classroom with these lessons, articles, and activities to better understand how we explore climate change.
TAGS: Earth, climate, geology, weather, EMIT, Teacher, Class, Lessons, Earth Science, Climate Change, Dust, Global Warming, Educators, K-12, Teachable Moments