2023-12-12 12:44:55
NASA’s EMIT produced its first global maps of hematite, goethite, and kaolinite in Earth’s dry regions. Mission collected billions of measurements of ten minerals that can affect climate in dust storms – NASA/JPL-CALTECH
MADRID, 12 Dic. (EUROPA PRESS) –
NASA’s EMIT mission has created the first maps of the source regions of mineral dust, to study a dozen key substances believed to influence climate change.
When the winds lift these substances into the air, cool or heat the Earth’s atmosphere and surface, according to its composition. Understanding their abundance around the world will help researchers predict future climate impacts.
Launched to the International Space Station in 2022, EMIT (short for Earth Surface Mineral Dust Source Investigation) is an imaging spectrometer developed by NASA’s Jet Propulsion Laboratory. The mission fills a crucial need among climate scientists to obtain more detailed information about the mineral composition of the surface.
By examining the Earth’s surface from 410 kilometers above the ground, EMIT scans wide areas that would be impossible to study for a ground-based geologist or aircraft-borne instruments, but it does so while effectively achieving the same level of detail.
To date, the mission has captured more than 55,000 “scenes” (80-by-80-kilometer surface images) in their study area, which includes arid regions within an 11,000-kilometer-wide band around the Earth’s midsection. Together, the scenes comprise billions of measurementsmore than enough to create detailed maps of the surface composition.
The mission has also demonstrated a variety of additional capabilities in its 17 months in orbit, including detecting plumes of methane and carbon dioxide emitted by landfills, oil facilities and other infrastructure, NASA reports.
Scientists have long known that suspended mineral dust affects the climate. They know that darker, iron-oxide-rich substances absorb the Sun’s energy and heat the surrounding air, while brighter, non-iron-based substances reflect light and heat, cooling the air. However, it remains uncertain whether those effects have a net warming or cooling impact.
Researchers have an idea of how dust travels through the atmosphere, but the missing piece was the composition (essentially color) of the surface in places where dust typically originates, which until now has been derived from less than 5,000 sample sites around the world. Based on billions of samples, EMIT maps offer much more detail.
Beyond leveraging EMIT mineral data to improve Earth’s climate models, scientists can use the information to study the impact of dust on the ecosystems where it lands. There is strong evidence that particles settling in the ocean can stimulate phytoplankton blooms, which may have implications for aquatic ecosystems and the planet’s carbon cycle. Scientists have also shown that dust originating in the Andes of South America, as well as in parts of northern and sub-Saharan Africa, provides nutrients for the growth of the rainforest in the Amazon basin.
EMIT data can allow researchers to identify sources of mineral dust and gain a more detailed view of its composition, helping to estimate the journey of key elements such as phosphorus, calcium and potassium, which are believed to influence this long-distance fertilization.
In addition to tracking 10 key minerals that are part of its core mission – including kaolinite, hematite and goethite – EMIT data is used to identify a variety of other minerals, types of vegetation, snow and ice, and even substances produced by man on or near the surface of the Earth.
#maps #minerals #affect #climate #air